Babalouie ISF Maintenance Thread

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Stuff and I thought I had car ocd, that's TOO shiny. but nice.

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It's been 2 weeks since the Gyeon Mohs paint coating was applied, so it should have bonded to the paint and be safe to wash the car now.  And you can see the water-repelling properties.

It does also mean that dirt is less likely to stick, and everything just glides off when you wash the car.

But another detailing episode which was less successful, were the seats.  They were in good shape when I obtained the car, but I think I might have scrubbed the leather a little too enthusiastically when cleaning, plus a year's worth of wear and tear meant that there was a spot on the lower cushion where the colour had rubbed off.  The dark-coloured leather beneath was now showing, and it's super-obvious given that the rest of the seat is a lovely sparkly white.

The wear is exacerbated by the seat foam not being as plump as it used to be: this means that the leather folds and creases when you sit on it, which wears out the colour in the high spots.  This is in contrast to the passenger seat, where the leather seems to be pulled a lot more tautly.  Of course, white leather doesn't come from white cows, and automotive leather is hot-rolled with a polyurethane paint to give it colour and an even grain.  So it's all totally artificial but very uniform...however it means that when the surface wears, it's like a paint layer rubbing off, which doesn't have the distinguished aged-leather appearance that old cars might have.

My trimmer suggested this guy:  He sands back the leather in the spot that needs to be repaired, then has this three-step dye process where he mixes up the colour to match and sprays it onto the seat. 
And it came out...rather well.  We'll see how durable this new colour is, but initial impressions are that he did a great job.

The close-up pic makes the repaired section look more creamy and offwhite, but I think that's just the result of different lighting when I took the pic.  Overall the colour match is spot on.

Another little mod I picked up recently was this:

It's a JoeZ intake elbow, that replaces the stock plastic one.

Now, I don't think that there's anything terribly wrong with the stock plastic piece; the JoeZ item is slightly larger in internal diameter, and would flow a tiny bit better because it doesn't have the concertina-bit like the stock one.  Apart from that, there are no other changes and the stock airbox and filter element is untouched.

It's claimed that the new pipe adds 4.6rwhp, which is dangerously close to a seat-of-the-pants rounding error, but the main benefit I was after was a louder sound.  When stock, an ISF has a really lovely induction snarl when it goes past 4000rpm, but it's all calibrated to the usual tomb-like quietness of the cabin when stock.  The moment you add a noisemaker mod like an exhaust, the induction bark gets drowned out.  So it's said on the Lexus forums that the JoeZ pipe restores some of the induction noise to offset a louder exhaust, and I'm all for that.

And...yes I suppose it does make the intake noise louder.  As for that 4.6hp...I think that anything I might be able to feel, is probably the placebo effect of having just installed a shiny new mod, and/or is the result of the car sounding a bit more dramatic above 4000rpm.  But, it wasn't expensive, and took all of 5mins to install, so it's all good.

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Holy moly that engine bay is so clean..

When you are ever selling your cars please let me know, be like buying new!

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The latest addition to the ISF are some new shoes.

With an upcoming drive day with the Lexus F owners club, and a trackday, the old Michelin Pilot Super Sports didn't look like they'd survive too many laps of the track, so I decided to get a set of my favourite tyres; Advan Neova AD08R. The stock size is 225/40-19 and 255/35-19 which is strangely undertyred for what was Lexus' headline performance vehicle at the time.  My wife's bone stock IS250 comes with 225/255 tyres as well, and the tyre footprint is somewhat less than what was available on the M3 and C63 of the same vintage.  Even the later RCF and GSF came with bigger rubber at 255/275.

The stock 8in and 9in wheels can take wider rubber, so I decided to go for the common upgrade to 245/35 and 275/30, which bulge out the sidewalls noticeably compared to the stock tyres which have more of a stretched sidewall look.

And how does it feel?  It does seem to have more grip compared to the (2014-datecoded) old Michelins, and there is definitely more traction with the wider rear hoops, it's no longer breaking traction on a 1-2 upshift.  But also noticeable is a change in the steering feel, which seems to have lost a little of the old alertness on the first 1/8th turn of the wheel.  I guess it's the softer sidewalls of the new tyres, compared to the stretched-taut sidewalls of the old tyres.  And it does seem to ride a bit softer too, notwithstanding that the Advans have very stiff sidewalls for motorsport use.

So with the new tyres still feeling very green, we went along to the excellent drive day put on by the ISF/RCF/GSF Club Australia, which took us down the south coast for a nice lunch.  V8 sounds and eye candy as far as the eye could see :)

And today we headed to the track!

Apart from the new tyres, since the last trackday the brake pads have been upgraded to Endless MX72 Plus.  At the last trackday I'd fitted a brand new set of Brembo pads, but they wore to almost nothing before the end of the day.  I'd used these before in my old RX-7 and they were a good road/track compromise, with little noise and dust.

At the last trackday, I'd found that I was a half second quicker with the traction control set to Sport.  The Michelins weren't very consistent and it was too easy to overheat them with just a slide or two, so keeping the traction on seemed to keep the car straighter and there was just the right amount of power being doled out, allowing little powerslides without overwhelming the rubber.  So I started the day the same way, with traction on in Sport, and the new Advans were definitely much more consistent.  The old Michelins felt like they had a narrow sweet spot before they overheated, so you had to pick your battles with the traffic on the track, as to when you were going to go for a good lap.  In comparison, the new tyres seem to be at their peak for lap after lap, and so it wasn't long before we'd done a slew of laps that were slightly under the previous best time of 1'10.21.

But a couple of tenths better was all she'd do.  It did feel different this time 'round...the traction control didn't seem as intune with the tyres as it was before, and instead of gentle power-on slides, it now felt like the traction control was pulling the plug a little abruptly and costing us precious time accelerating out of corners. I suppose it's possible that the grippier new tyres might unload the inside tyres more, causing the traction control to come on more aggressively.

So I decided to try a session with all driving aids off, and surprisingly it was much better.  On the Michelins, it would transition to power oversteer a little messily, but on the Advans it's much, much more predictable; it was easy to hold a slight powerslide on the throttle and driving a little sideways doesn't feel like it's costing time. Straight away, the laptimes dipped below 1'10, we did a bunch of laps at 1'09.7-9 and eventually the day's best was 1'09.68.

And here's the in-car of the best lap.

There's still a little fine tuning I'd like to do...the car feels a little nose heavy, and notwithstanding the wider front rubber, is a little reluctant to rotate on corner entry.  It's very stable on entry, so it's hard to mess up a lap by backing into the turn too much, but a little more front end bite on the way in would be nice.  On the flipside, the balance on the power after the apex is just fine and dandy, so I'm a bit loathe to want to change tyre sizes.

As for the brakes, the new Endless MX72 Plus held up their end of the bargain and together with the Advans, you could do 5 or 6 laps within a tenth of your best before the car started to lose consistency. Where before, you had to save the brakes and tyres for a nice gap in the traffic and then go for it for one big lap; now the ISF seems to be able to stay at its peak for much longer.  Overall, the ISF is a little quicker than my old FD RX-7, which was a few tenths behind at 1'09.94.  Needless to say the FD is far more nimble and gets its laptime from finesse rather than brute force.  But the ISF has got heaps of brute force, so it's a little quicker, but a tiny bit less entry understeer would make it more entertaining.

I'm a little disappointed that the fancy new rubber is only a half second faster than the crusty old tyres, but it's nice to end a trackday because you ran out of fuel, compared to running out of brakes or tyres :) A full tank disappeared in 55 laps :)

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On some of those corners - 0:06 and 0:024 - it looks like the car is in too hot, hence the sideways power slide, losing time. 

Compare these to corner at 00:52 - nearly got it correct, it would have been a nice fast exit. 


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Where abouts did you get the Joez intake from as I like to get one ?

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12 hours ago, Gen03 said:

Where abouts did you get the Joez intake from as I like to get one ?

I got it second hand from another ISF owner

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Late last year I decided to have the side bolsters of the driver's seat repaired.  Due to the big bolsters on the seats, pretty much all ISFs have unusually high wear on the edges of the seats.  A dude came to my house, sanded the leather and applied a new coat of paint which looked great for a while.

But it didn't last.  Basically the foam under the leather was collapsed, and everytime you sat on the seat, the leather would crease and fold.  This flexes the leather and cracks the newly applied paint, which in my case started flaking off within a month.

It's not the fault of the paint guy, in fact he did caution me that unless the foam was repaired, the repair possibly might not last very long.  And so you see today, the leather is saggy and where it's creased and folded, you can see the darker leather underneath the surface. 

In comparison, the leather on the tunnel-side of the seat is nice and taut and you can't make it bunch up like the outside bolster, no matter how hard you try.  So the foam has to be repaired before we try anything else.

So I took the seat out of the car and dropped it off at my favourite trimmer.  $250 and a couple of days later, the outside bolster was a mirror image of the inside one again.

The creases and folds are now pulled tauter, which kinda makes them more obvious now 🙂  But you'll also notice that the leather is still a little wavy, and isn't perfectly flat and smooth as it should be.  More of this anon.

Now before we get too carried away with what happens next, we should talk about leather.  The grain that you see on leather seats isn't natural at all, but is in fact a pattern that is hot-rolled into the leather with a polyurethane coating.  That's why leather seats are such a perfectly uniform grain.  When leather comes off the cow, it peeled into 5 layers. the top and bottom layers are used for handbags, book binding and shoes, and it's the middle layer that gets used for seating.  It has no grain, which is why an artificial grain has to be imparted on it.  So it gets rolled to install a plastic outer layer, which is both the colour and the grain.  And when modern seats age, rather than look mellow like a vintage piece of furniture, the colour layer peels or flakes off and the seats look terrible.  

And the reason why we can't have leather like they had in cars in the 1950s, is because the ye-olde tanning process used chromium and other awful chemicals, and it's no longer legal to make leather that way.  Even India has banned it 🙂

So the repair that we're about to apply is called a "dye" but it might be fairer to call it a flexible coloured coating.

Years ago I had to restore a leather steering wheel, and so I bought this Leatherique kit which worked pretty well.  There was enough left in the kit, that all I had to get was the colour, which was mixed up at  to suit the seat.  

There's multiple steps, and as you'll see the whole process takes about a week. The first step is to apply the Rejuvenator, which is like a moisturising oil.  It's not oil and is actually water-based, but it goes on like a sticky, honeylike oil.

The idea is that it seeps into the leather to soften if you've been paying attention, then you might be thinking that it can't possibly soak in, because the leather has that hotrolled plastic coating, right?

And you'd be correct!  The next morning, the areas where the leather is good, still show a thin sticky layer of the stuff...but the areas where the leather coating was damaged and the base leather was exposed...on those areas the sticky goo had been totally absorbed.

I think this is important, because leather dries out once the coating is breached.  So this is the last chance to get some moisture and flexibility back into the damaged sections.  Also, there is still some absorbtion in the "good" areas of the seat, because there are always pinholes and micro-tears in the coating which let the stuff through.  And the large sections which are perforated absorbed the stuff the best.

Remember how the leather still looked a little wavy after the repadding?  Well, the Rejuvenator seems to have fattened up the leather in the creases and made the whole thing more supple, so straight away you notice that it's flatter and more relaxed-looking.

Next step is Prestine Clean, which is a cleaner/solvent that's brushed on... 

And then you use a leather brush to clean/scrub...

...before wiping away the dirty detergent with a damp cloth (that you need to keep rinsing)

Rejuvenator and Prestine Clean are what Leatherique recommends to clean and condition leather as part of your normal maintenance, so I did the whole seat, which now felt noticeably clean and softer.

You then have to wait 48hrs 🙂 before progressing to the business end.  Which involves sandpaper.

You fill a bowl with the Prepping Agent, dip some 600 emery paper into it, and go to town to remove the old damaged dye and leave a smooth surface.

After all that, wipe down to see that you have well and truly passed the point of no return 🙂  Run your fingers across the leather to see if what you feel is a totally smooth, even drag. If you can feel it on your finger tips, you'll see it under the new dye. In this pic below, you can actually see on the left, that the paint repair was actually slightly browner than the seat colour.

Then you mask the black stitching with electrician's tape, which I figured was more flexible to accommodate the bumpy stitching.

Shake the crap out of the bottle of dye, pour it into a container and stir it again...then get a clean cloth, rinse it and wring it dry, then form a "puff" with it that has no edges.

Then rub on the dye with light, circular strokes, like polishing a car.

I start off with light, thin coats, which dry in 10mins with a hairdryer.

After a couple of can still see the dark patches where the old colour came off. 

But after about 6 light coats, it's looking pretty good.

The finish is an even semi-matte, and you can't see any strokes or splotches.

So...a pretty good result 🙂

The only thing I'm not 100% happy with, is that the dye is maybe a little more yellowy than the original colour.  When the guy mixed up the colour, we smudged a little onto the seat and the colour match looked spot on, so maybe I didn't shake or stir it enough.  But then again, this is in my kitchen under downlights and sitting on white tiles, so perhaps it isn't noticeable once it's in the dark cabin. The old spray repair was actually more brown than it should be and wasn't noticeable, so fingers crossed.
7238DA09-2C13-46AA-8FA1-AEBF87365D23.jpg'll be 48hrs before I can sit in it 🙂 As to whether this repair lasts, I guess we'll see.  But the fact that the foam is back to its old self again means we have a significant head start.

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Nicely done - i have the same set of products to repair some slight bolster wear on my black leather IS-F seats. Just need to wait for a long weekend of some holidays to commit to it because its obviously a time consuming ordeal.

But, your seats look good. Please let us know how it holds up over the coming months.

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In tonight's episode of More OCD With Leather For Fun & Profit, we finish what we started.

After the last bit of restoration on the driver's seat, it looked pretty good in the sunlight, where the colour seemed a good match.

But before we can move on from the driver's seat, there is something that needs finishing that we couldn't do with the rest of the seat.  The piped edge of the side bolster had a little wear in the colour, and as fixing it requires that stitching to be masked from the other side (the side that we were fixing), it had to wait until the main repair was dry and cured.

The leather was cleaned and treated along with the rest of the seat, so as before, the next step is to sand away the damaged dye with 600 grit paper and the Leatherique Prepping Agent. 

Since we're just dyeing a very narrow strip, I'm doing it with by dabbing on the dye with a cotton bud.  I found that if you sanded all of the old dye down to the parent leather, the new dye gets soaked up very fast.

And after a few coats, it's looking good again.

The next step is to clean and moisturise the other three seats.  The pre-dyeing steps with the Leatherique Rejuvenator and Prestine Clean are recommended as a normal maintenance for good leather, so I figured I might as well... 

First step is the Rejuvenator moisturising fluid.  You'd think that you'd clean it first and THEN moisturise, but Leatherique do it the other way around.  So the sticky oily fluid goes onto the leather with a brush.

It absorbs better in the heat, when the fluid becomes thinner, so i roll up the windows and idle the car for 20mins with the heater on full blast to at least get "some" heat in there.

The next day, some of the stuff has been absorbed, but as the other seats are in actually pretty good shape, they didn't have any high-wear areas that soaked up all of the fluid.

The Prestine Clean is then sprayed on, given a quick scrub with a leather brush and then is wiped down with a damp cloth (that you have to keep rinsing out in a bucket of hot water).
F1097AFE-A22F-48C2-A23B-151692BAE1AD.jpg can't argue with the result.  By moisturising first and cleaning later, there is no greasy sheen to the leather and it's really dry, clean and noticeably fatter and softer to the touch.


The last job (I promise) is to see if I can knock the shine off the steering wheel.  Now, I reckon that some of the shine is due to the mechanical polishing of the leather by your hands over the years.  But I reckon at least some of the shine would be from crap on your hands being embedded into the leather and polished, too. 

So on goes the Rejuvenator moisturising fluid to sit overnight.  It's meant to soften the dirt and oils and make it come off when you do the cleaning step.

Next day, it doesn't look like much of it has been absorbed at all.  But I figure it might become more absorbent if I give it a good clean and repeat the process.

So it gets a good scrub with Prestine Clean and the brush, before the Rejuvenator goes on again for another night.  Next day, it does seem to come out better after the clean, and in the low-traffic areas, the shine is totally gone; pic of a brand new gearknob for comparison.

On the higher-traffic areas like the outer rim where your right hand goes, I'd say 70% of the shine is gone, and the wheel is noticeably softer and squishier to hold.

Ok, that's more 🙂

The Facebook F club show and shine is on Sunday, and I figure the interior is as done as it's going to get 🙂

...for now.

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Recently Bridgestone were kind enough to send me a set of their new Potenza S007A to try out. 

They're based on the S007, which Bridgestone developed as the oem tyre for the Aston DB11; so these are their latest offering for high-end supercar tyre market, and sits at the top of their road tyre range.  They're aimed at owners of Lexus F, AMG and M-cars, so I was pretty curious as to how they'd go.

Once they were fitted, I immediately noticed that compared to the Advan AD08Rs, road noise was much less noticeable and the new tyres rode with a bit of a plush edge.

When pushed on a winding road, the steering was bit calmer and less alert, but the breakaway characteristics were quite soft and gradual.  So they give you a lot of feedback and you feel more comfortable really leaning on the tyres. Wet grip was an improvement on the AD08Rs, and dry grip was about the same on the street.  So as a pure road tyre, I'd say that I like them a lot; they feel exactly like a premium luxury sports tyre should.

But the other piece of the puzzle, is how they go on the track, so without further ado....the ISF and I head to Wakefield Park. 

Now, to save you the suspense, we ended up with a new PB:

When I first got the ISF, she did 1'10.2 on the oem fitment 225/255 Michelin Pilot Super Sports.  I then fitted Advan AD08R in a wider 245/275 size, and the laptime dropped to 1.09.6. So I'm pretty impressed that the Bridgestone S007As managed to beat that by a few tenths.  But straight from the first run, it was easy to get into the 9s, the grip level felt great straight away and there wasn't any warming up needed, and they kept the same soft breakaway characteristics from the street, so it was easy to get stuck into it straight away.

You can see in the in car vid that you can hang it out there and have the car constantly sliding a little, and there is enough predictability to avoid making (too many) mistakes.

But this is where it gets interesting.  I'd been experimenting with tyre pressures all day, and the S007A's unusually seemed to be fastest with a fairly low pressure of 35psi hot. I tried raising the hot pressures to 37 and 40psi, and times fell to 1'09.6.  And all throughout the day, I did notice that the rate of wear was higher than I would have expected, and the stiffer pressures didn't really make any difference.  

After 3 sessions, they looked like this:

They were fastest on the first three laps of each session, and after that the laptimes would start to worsen as they heated up, and they needed about 3 cooldown laps before they were good to go again.  In that sense, pretty similar to the Michelins.

I think the thing with these S007As are that they have quite a soft compound, with a treadwear rating of 240.  So quite a bit softer than say a Michelin Pilot Super Sport at 300 but harder than the AD08R at 200.  But subjectively, the S007As do feel softer and gummier than the Advans.  This explains the great grip and feel, but also the high wear rate. I've only had them for a few weeks, so I can't say what their longevity is like on the street, but they looked perfect after a winding road thrash, so I suspect you only burn them up when you're on the circuit.

So in the end, I find myself in a strange position of having these tyres which are capable of a great laptime, but aren't actually that well suited for trackday use.  But as a pure road tyre, they're really, really good.

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Stuff those tyre are punished, thanks for the vids, what pilot sports were you using I'm thinking on ps 4s cheers.

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They were the old Pilot Super Sports, so the model that was replaced by the PS4.


a fair bit slower than the Bridgestones, almost a full second, but more durable

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Another week...another trackday at Wakefield!  This time, it was a trackday with the Lexus F Owners Club, which was part of a timed day with Trackschool.

Yes, yes it was only two weeks ago that I last went to Wakefield; where we scored a new PB on the Bridgestone S007As.  Since then I've refitted the Advan AD08Rs as they're more suited to continuous lapping, so I was hoping to at least match the 1'09.3 that I got on the Bridgestones.

But alas, it was not to be and the best I did was a 1'09.8, which is in the ballpark of my PB on Advans of 1'09.6.  

The AD08Rs wore nice and evenly (unlike the Bridgestones) and were nice and consistent all the way throughout each session, but I did notice that it was harder to get a time out of them. With the S007As, they felt like they were at their peak on the first corner after coming out of the pits 🙂 and I was into the 1'09's straight away.  But with the Advans I have to work up to it and it seems like a bit of an achievement when I do finally crack into a 9 halfway through the day.

The S007As feel like a road tyre, with a squidgy, soft edge to the grip limit; so I can get right into it and I know where I stand.  The Advans are more of a racy tyre with a more distinct edge to the grip. Looking at the in-car footage, it does look like I'm fidgeting and correcting the car a lot more than I was a couple of weeks ago.

Now I'm wondering if it's my driving style I have to change.  The ISF points quite well into a corner, but between turn-in and the apex, it does wash away into understeer a tiny little bit.  And in the two critical corners (the 90 degree right hander off the main straight and the sweeping right hander on the back straight) you can hear that I'm quite late onto the throttle, as I'm waiting for the front end to settle.  In the tighter corners, you can get onto the power early and bludgeon your way past the apex with oversteer but I think I am losing quite a bit of time in the faster stuff.  It would be nice to add some front camber (which isn't adjustable :)) but maybe I need to rethink my approach and take a slower entry, turn in earlier and power on earlier.  It has occurred to me that maybe I'm just overdriving it.

So I reckon I still haven't quite worked out how to drive this thing yet, but it did okay in the results.  10th overall out of 65, just pipped by a C63S and a well-driven M140i.
Times.png be continued 🙂

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I was going to do an update on how the seats are wearing, 4mths after the big restoration.  The verdict is that the high-traffic areas are a little grubby and I can't seem to scrub it clean:

And there is one tiny spot where the new dye is flaking off, in the valley of a crease in the leather.

So I went to see Rob at PPPCo, who are the Leatherique importers and he suggested that the grubby part could just be the new dye being too thin, and it's exposing some of the old dye underneath.  He also recommended that in the flaky spot, to really work the new dye into the leather with your finger, instead of gently wiping over it like the instructions say. He also noticed that the new dye was a bit more yellowy than the rest of the seat, so he offered to make up a new bottle of dye for me. 

And it's a much better color match.

So...let's give it another 4mths and see 🙂

The other thing that happened recently, is that I've been chasing better handling and laptimes, and so we bought a thing.

They're HKS Hipermax IV GT coilovers.

I'd had a really good experience with the Aragosta Comfort-spec coilovers in my old FD, which were the base-model Aragostas.  But their ISF range only starts near the top of the line with the Type-SS, and with the current exchange rate these would have been around $4500.  So for about half the price, the HKS ones seem like they'd be worth a try, especially since they'd received generally very positive reviews on Clublexus.

I decided to do the swap on that 37C hot day last Friday, so if there are fewer pics than my usual standard, it's because my motivation started to decline almost immediately 🙂 First job is to remove everything in the boot.  This might seem a bit of overkill, but the side panels over the shocks are very hard to remove unless you do.  So the first step is to remove all the clips from the top panel of the boot, then pull it backwards to unclip it from the body, and undo the wire for the light.

Then the whole top, back and floor covering all comes off in one big piece.

Unbolt the 4 luggage tie down hooks, remove the 3 clips and give the rear garnish a sharp upwards tug to pop it off its clips.

Then go around and remove the last few clips holding in the side trim panels.

And now you can remove the last of the boot trim to expose the shock tops. 

The next step might also seem like overkill, but it really does make it a lot less awkward to remove the old shock.  Remove the zillions of clips and nuts and take out the guard liner.  This exposes the whole top half of the shock.  You'll notice that rather unusually, the shock is not only mounted at the top, but there are also two bolts that secure it to the side of the body too.

The next part isn't so easy. The outer bolt to the upright, the shock bolt and the away bar bolt all have to be removed.  

The reason why it's tricky is because the factory torque specs are incredibly tight. The shock bolt is done up to 165Nm, which is impossible to undo with a spanner, and you'll need to get creative with extension bars to get them off. If you don't have the right combination of socket handle and long pipes (or jack handle!) then this is where you'll get stuck.  It'll help to have a second person on standby to lean on the extension bar, while you hold up the front to prevent the socket from slipping off and rounding off the bolt.  Rather unusually, you remove the bolt rather than the nut; the nut is actually keyed to little slots in the suspension arm (to prevent them from coming loose) so you loosen them from the bolt-side.

Out with the old, and in with the new 🙂

I'm installing the new shocks at the HKS factory specs, which will result in just a very modest drop in ride height.

The rear shocks with with these nifty extensions...

So that when you make a hole in the side trim, the adjusters can poke through.

To make the hole, I'd marked the spot with a pen before removing the boot trim.  The top of the stock shock is just a few mm below the trim, so if you felt around with your fingers, you could tell where the right spot was.

The HKS instructions are great, there is an English language section with torque specs and everything: do up the lower arm bolts to the insane 160Nm for the upright and 110Nm for the shock bolt. Oh lastly, make sure you bolt the ride height sensor like this: with the linkage coming off the suspension pointing upwards.  

There are ride height sensors front and rear, they are for headlight auto-levelling, and it's possible to reattach it with it facing downwards, and you'll get a 'Check Headlight System' warning light as the car spazzes out about why the rear suspension is at a catastrophically weird angle.

Now that the rear is all done, you can start on the front. 

As before, the trick part is getting off the 160Nm shock bolt, and given that the front brakes are huge, you have to somehow get a long socket extension in there, as well as a massively long breaker bar. The other things that needs to come off are the ABS line bracket that bolts to the stock shock, and the sway bar bolt (remove the one from the sway bar end) 

Then you'll have to use a balljoint separator to split the wishbones. This is because the shock is trapped inside the wishbones and is too fat to be wiggled out without making some extra room.

But once the shock is out, it just takes a few minutes to slot in the new one, not forgetting to bolt up the ABS line bracket to an adjustable bracket that's held in place with a hose clamp on the HKS shock. 

And we're done!  The fronts take maybe only a 1/3 of teh time it takes the rears, and it was about 4hrs from go to whoa.  

The resulting new ride height is a 10mm drop at the rear and a 18mm drop at the front.  I think it looks just nice, without being too slammed.

In terms of ride, it makes a great first impression.  All ISFs have this very taut, firm quality to the ride with lots of small, sharp vertical movements, even on a smooth road.

I've left the the Hipermaxes at their factory setting of half-stiff, and they have much more of a conventionally pliant ride, which...for middle aged men of a certain body type, means no more moobs-jiggle 🙂

The new shocks to feel ultimately stiffer, it corners flatter and when you hit actual bumps or speedhumps, you can tell that the suspension movement is a lot less and body movement is more severely checked.  But compared to the stock setup, it's much more serene more of the time.  At full-stiff, it feels about as jiggly as the stock setup, and from full-soft to full-hard, there are 30 laborious clicks of the adjuster, but not really a game-changing difference in feel.  Certainly you won't feel 2 clicks and would struggle to feel 5.

As for why the stock suspension feels that way; I suspect that Lexus was aiming for a "signature" F chassis feel.  The stock setup is actually conventionally soft, it absorbs big bumps well and on track it rolls heavily onto the outside front wheel.  But the rest of the time it has an overly-taut feeling, where it reacts to the tiniest little surface change.  I think that's the feel that Lexus was going for, where it feels like the suspension hasn't got any slack in it at all; and the car feels hyper-alert and communicative.  And Lexus did do a good job of retaining this character as each version of the ISF got more comfortable. 

On the new suspension I do have to say that it feels a little bit lazier dynamically, as if you have to turn the wheel more to get it into a corner.  It's all in the head though, and the flatter, firmer new cornering stance should bring dividends in laptime. I guess we'll have to see 🙂 but at the moment I am enjoying the more refined and expensive feeling new ride quality and subtle amount of slam.   

How do they compare to my personal favourite Aragostas?  Hmm...well I reckon the Aragostas feel a little sweeter, and pull off a big increase in spring rate without feeling firm at all, whereas the HKS do ultimately feel firmer than stock.  The Aragostas also have a wider range of adjustment...but for half the price the HKS are a good compromise.  Bring on the next trackday, this should be interesting 🙂

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Now that we have nice suspension, I figured I'd fit some parts that I bought ages ago.

They're lower wishbone bushes from the RCF.  The ISF has these huge rubber bushes which are the size of your fist, and while they're an upgrade from the regular IS250/350, when Lexus released the RCF, they made the bushes stiffer again.  They go back here, at the rear of the lower front wishbones, and the big rubber element provides a lot of cushy fore-aft movement to absorb bumps, but it also has a contribution to the front toe control as the wishbone moves around within the rubber.  

To replace them is quite simple.  Just undo all the bolts holding it on, and it would pretty much just slide right off, if it weren't for this protruding lip on the crossmember casting. 

To get around this, you can use a big screwdriver, pry bar or the handle of a socket breaker bar, as I'm doing here.  There's plenty of flex, so you can just lever down the wishbone enough to slide off the old bushing.

The alloy housing looks the same, but the rubber element does have different markings. They're handed left and right though, but it's hard to mix them up as the front-facing bit of the bushing crushtube has a cone shaped profile...
IMG_7647.jpg match the shaft on the wishbone.

But the new bush slides on easily enough...but I leave the wishbone nut a bit loose.

Jack up the suspension so that the wishbone is roughly in the same spot as normal ride height, and then tighten the wishbone nut.

This means that at normal ride height, the rubber element isn't twisted.  If we'd bolted it up with the suspension at full droop, the rubber would be a little twisted when it's at normal ride height, and it'll wear out quicker.

And how much stiffer is it?  

Well I decided to test it by clamping the bush in a vice, then using a breaker bar to see how much deflection there is, using the highly-accurate and totally-scientific Torque Arm device. 

And...well surprisingly the difference was very noticeable.  It didn't take much strength to deflect the ISF bushing 7-8mm, but it took considerably more effort to deflect the RCF one half as much. But to be honest, all this proves is that a brand new RCF bush is a lot stiffer than a 74,000km old ISF bush.  But stiffer is stiffer, and the steering does feel noticeably tighter and with a crisper feel just off centre.  After a wheel alignment, it looks like we have just a tick over 2 degrees of camber all round at the current lowered ride height, so this should hopefully translate to better tyre wear on the track. 

The other thing I did recently was to swap out spark plugs.  Std service interval is 100,000kms, so they have 26,000km to go before they need to be replaced, but hey why not.  

But unfortunately this wasn't easy...the spark plugs are in there...somewhere.

In theory it's simple enough.  Each plug is topped with its own coilpack, which is screwed to the head with a small bolt.  Remove the connector and bolt, give it a wiggle and... 

...out it comes.

The challenge is that half of the plugs are really hard to reach, and require a whole bunch of engine bay furniture to be unbolted and moved in order to make space for the spark plug tool.

And speaking of which, it was lucky that I had a socket extension that was just long enough...

And protruded from the spark plug hole at just the right height to allow the socket handle to swing.

New versus old Iridium plugs.  The old ones visibly seem to have a larger electrode gap from wear, but they aren't too bad.


It took about 45mins to do all 4 plugs on the driver's side, which is the "easy side".

The passenger side is a bit more involved, and it's impossible to do the 2 rearmost plugs unless you remove the battery box. Once you do that, you see the electric power steering ecu underneath, which also needs to be moved aside to access the battery tray bolts.

The EPAS ecu has these funky double-action connector locks...first you use a little screwdriver to prise out that little black tab, then you flip back the U-shaped lock and the connector can be unplugged.

Unplug one side of the EPAS ecu, flip it up and you can unbolt and remove the battery tray.  And now, the two most inaccessible plugs are now surrounded by a rather luxurious amount of space.

Ironically, I thought the frontmost plug on the passenger-side would be easy, but the aircon hardlines were in the way, and it was impossible to get the spark plug tool in there.  So I found this, an old Porsche plug tool, which has a bendy bit in the middle and could just about be wiggled into place.  

It's not quite long enough, but for just one plug, it was good enough and a lifesaver (aircooled 911s are even worse for plug access, so Porsche have some nifty service tools)

And with that last one done, start the engine, and it'll cough and immediately stall.  Which is supposed to happen when the ecu has been reset (because the battery was unplugged for a few hours).  Start it again, and let it idle for a bit while all the systems boot up and do their thing.

Does it feel any different?  Hmm....well after almost two and a half hours to do the swap, it's maybe a tiny bit smoother at idle, but that's all 🙂

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One thing I haven't managed to do with the ISF yet, was take it to the drags.  So when the Lexus F Owners club organised a night at WSID, it seemed like a good chance to see what the car could do. It was the first ever drag event for the club, and we had five ISFs and one RCF turn up.

Winning means cheating, so there's no way that I was going to rock up without trying to get an advantage over the other guys 🙂  So to start with, I rolled up with just fumes in the tank, and all the engine cover plastics removed.

The stock ecu is a bit of an overprotective mother, and it is way too keen to dial back the power to save the engine.  So the experience that everyone has with ISFs at the drags, is that the car progressively gets slower as the night progresses.  The engine bay heats up, and the insulated engine cover retains all that heat, which causes the intake air temps to rise and the ecu dials back the timing as a result.   So between runs, everyone popped the bonnet to let out the heat.

The first run was thankfully a good one: 12.88 at 113mph.  I was hoping for a sub-13, and having that first run in the bank meant that I could relax and enjoy the rest of the event and experiment a little to improve the time.

In the end, the approach that seemed to be best was: Sport Mode, traction off, manual shifting after one bounce off the limiter, and no brake stalling off the line.  I suspect that, like many modern cars, the ISF might have a torque limiting on a brake-stall, so stalling it up to 1500rpm on the launch seemed to actually make it bog down a little.  The best launch seemed to be to hold the car lightly on the brake with the left foot....right foot poised over the accelerator, the lift the brake and mash the throttle on the last yellow light. You'd get a little hesitation off the line, then at the 4000rpm point, the power would come in, and you'd get a little flurry of wheelspin, and I held it flat through it.

After 4 runs, we decided to park up the cars and have a chat for a bit to let them cool down, and in the meantime it got dark and quite cool.  So that was ideal and everyone got better times after that.  My times got down a little bit more to 12.7 @ 114mph

It was an interesting comparison against the other F cars.  Everyone had different mods, and my car might be faster in the first part of the quarter or the second half, none of the cars were exactly equal, although in the end the times were very close.  The RCF has an axleback exhaust and got down to a 13.041 @ 110mph, another ISF with headers was at about the same time as me, and the ISFs without a full catback exhaust and only an axleback, were a couple of tenths behind.  Dead stock was 13.095, so overall not a huge difference in times.

I suspect the trick with getting consistent times with the ISF, is to manage the ecu.  I'd done a top engine clean (kinda like seafoam) changed the plugs and air filter, so I should have less chance of the ecu recording a misfire and dialling things back.  I'd checked the ecu with the Toyota Techstream software earlier that day, and the KCLV ("Knock Correction Learning Value") was nice and high at 21.0. I believe that's the key metric for the ecu to control power output, if the value is high, it means that the ecu is nice and content, and if the value is low, the ecu will be in overprotective mother mode, and basically will have the motor tucked up on the sofa under a blanket with chicken soup (and the power output will be potentially noticeably less).

I'll do a proper post later with my findings about the ecu and what it reacts to, but I'm pretty happy with the 12.7 🙂

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Good write up when working on any suspension a impact gun is invaluable😀 and why didn't you go with the RR lower control arm bushes, I put them in mine and yes they work great no more brake squirm they just tighten the front end up so much. Sounds like you had fun at the drags cheers and thanks again for the pics and vids.

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On 12/16/2018 at 11:14 AM, 2bling said:

Good write up when working on any suspension a impact gun is invaluable😀 and why didn't you go with the RR lower control arm bushes, I put them in mine and yes they work great no more brake squirm they just tighten the front end up so much. Sounds like you had fun at the drags cheers and thanks again for the pics and vids.

I've had/have poly bushes in my other cars, and I prefer the softer feel of a rubber bush. Also the RCF bushes are dirt cheap at $100pr from Amayama 🙂

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Stuff that is cheap what's there postage like, and who did you get your suspension through cheers.

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Hi Babalouie - Leatherique Response

Firstly I think you have well reached the point where a number of new updates in this thread should really be a dedicated topic / thread in their own right ... there is so much good stuff in here!

The first I wanted to thank you for doing properly was the update re repainting your driver’s seat using the Leatherique process.

This was so much better, more informative and professional than the other clown who posted about touching up!

You can clearly see the difference and moreover the proof is the long lasting wear. 

I really appreciated your note re the foam replacement in the leather seat to ensure it doesn’t just wear off the same spot again!

Your detailed instructions and photos are perfect too and very easy to follow step by step.

Pleased to note that Rob replaced the original dye ... he was spot on with mine, twice! Very experienced and nice mature guy who knows what he is talking about and happy to help!

Also pleased to note you got such a great outcome after taking your time and doing to right!




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