Modifying Your Isf Intake

[marvin]

Hi there fellow ISF lovers,

I have been doing some research with regards to intake options for the Lexus ISF. I thought I might post my findings for everyone to discuss and for others looking to modify their ISF to find it all in one place.

Please note: the “Pros & Cons” are my findings on other forums and comments made on these particular items. Obviously people who have purchased these products would have a better understanding and I fully encourage everyone to add information & correct me if I’m wrong! Cheers!

The following is a range of Cold Air inductions available:

Injen

Cost: $250 (approx) + Shipping (on eBay)

Claimed power gains: +26.5HP & +37.5f/LBS

Colours available: Black or Chrome

Pros: If you believe the claimed gains this is a very good piece of kit for the dollar!

Cons: Installation instructions not quite clear. Not fully shielded.

K&N

Cost: $300 (approx) + Shipping (on eBay)

Claimed power gains: +22.4HP

Colours available: Grey

Pros: Good quality, clear instructions(installation video available on Youtube)

Cons: Costs a bit more than the injen. Not fully shielded.

Tekeda

Cost: $300 (approx) + Shipping (on eBay)

Claimed power gains: +16HP & 15f/LBS

Colours available: Black or Chrome

Pros: Fully seals, fits directly to factory intake box. Easy installation.

Cons: Costs the same as the K&N but has less claimed power increase in comparison.

SRT

Cost: $800 (approx) + Shipping (SRT website)

Claimed power gains: +HP & f/LBS

Colours available: Chrome

Pros: Some serious power gains (If you believe the claims)

Cons: Price. Also the Piggyback unit that comes with it has had some bad comments about its quality and performance.

Now that covers most of the popular options with regards to ripping out your air box and replacing it with a full cold air induction system. Another option available is to replace just the intake tube from the air box to the intake manifold. All of these options look quiet easy to install.

The following is a range of Intake tube replacements available:

JoeZ

Cost: $140 (approx) + Shipping (L-tuned website)

Claimed power gains: +5HP & 5f/LBS

Colours available: Blue & Black

Pros: Cheap & good looking way to add a few ponies & dress up your engine bay.

Cons: May suffer from heat soak in hot weather.

HPS

Cost: $170 (approx) + Shipping (Figs engineering website)

Claimed power gains: +4.6HP & 7.2f/LBS

Colours available: Blue, Black or Red

Pros: Silicone design wards off heat soak.

Cons: Haven’t heard much bad about this product yet…..

iCode

Cost: $399(approx) + Shipping (L-tuned webside)

Claimed power gains: ?HP &? f/LBS

Colours available: Black

Pros: Silicone design wards off heat soak.

Cons: Price…. I may be wrong but I don’t really see how you could charge this much for something that is practically the same as the HPS product.

Carson

Cost: $229(approx) + Shipping (L-tuned webside)

Claimed power gains: HP & f/LBS

Pros: Silicone design wards off heat soak.

Cons: Price…. I may be wrong but I don’t really see how you could charge this much for something that is practically the same as the HPS product.

Now to maximize these intake tube options I gather you would want to include a high flow panel filter. Here are some options below:

K&N, AFE, HKS……. And the list goes on and on.

Now I haven’t picked any of these options just yet but I would love to hear your opinions and to any newbies I hope I have help point you in the right direction. Like I said earlier I have put this list together from my own research and the “Pros & Cons” are what I have found from various other forums and comments. I’d also like to add the list is of the more popular options I have found. People who have purchased these products will have far more experience and I fully encourage their input in this thread!

Cheers!

[RecursiveLoop]

I've gone the HPS + AFE dry filter route, pretty cheap and easy to install, no risk of CEL. Definitely better throttle response but no dyno results to confirm power increases.

[marvin]

Nice yeah that is a pretty popular set up. What do you mean by CEL?? Also is the AFE filter a reusable filter like the k&n??

[RecursiveLoop]

Yes it's a reusable filter. CEL = check engine light

[marvin]

Alright awesome. Have you noticed any sound difference compared to stock?

[RecursiveLoop]

I'm still waiting for the HPS tube to arrive, but the AFE filter alone gives a bit more induction sound than the stock air filter, especially when cold.

[ilv1004s]

theres is minimal sound difference

i have 3 intake set up on my isf that i tried

Takeda

Injen

Joez + AFE (which is the similar to HPS tube + AFE

Joez+AFE is pretty much stock

Takeda is sam as stock untill the flaps open

but sounds like a ram pod after the flaps open above 3K + rpm

Injen is loud all the time (which i prefer)

so out of the 3 i am running injen

hm.. performance???
there are gains which are not that noticeable

on the dyno i did make another 5-7kw atw depending on each intake

[Ultrasonic IS F]

Hi all

I fitted a HPS intake tube and AFE air filter about a month ago and thought I'd report on my findings. Very easy install. Parts fitted well. The main difference I have noticed is that when changing gears manually at high revs the change is even smoother than before. I found previously when changing up (say 2nd to 3rd) at high revs the gear would "bang" in a bit. Not unpleasant but a noticeable feeling. Now it seems to change much smoother with less "bang". Secondly, perhaps a little less induction sound across the rev range. Still roars above 3k rpm but maybe not quite as loud. No real sense of performance improvement as such but perhaps feels a little stonger at the top end of the range (perhaps because it seems smoother and breathing easier).

Anyway, just my impressions.....

[- Raven -]

Nice one Marcus! I installed my AFE dry panel filter yesterday, but I'm still waiting on my HPS intake tube which should get here today hopefully.

Love the placebo effect from changing filters haha! My butt dyno says it's got a bit better response lol! :)

[Keilos]

Hey guys,

Just picked up a MY12 and looking to make a few small mods.. just wondering where you get the Injen intake from? Struggling to find it even on eBay!

[Mark78]

It appears that JDMyard in Sydney are the distributers for Injen

[Keilos]

Yes, but they don't appear to support Lexus. Well, not on their website anyway.

[Sparky]

Great info there.. From what i can gather though the stock intake does a pretty stellar job power wise, and its important to maintain the dual intake system for low down torque. A drop in filter and intake pipe (HKS etc) seems to be the best option.

[MR2QIK]

Great info there.. From what i can gather though the stock intake does a pretty stellar job power wise, and its important to maintain the dual intake system for low down torque. A drop in filter and intake pipe (HKS etc) seems to be the best option.

I don't quite agree with that. MotoIQ did a test on their own ISF with a K&N intake & recorded one of their largest power increases for an aftermarket intake modification.

http://www.motoiq.com/MagazineArticles/ID/1827/Project-Lexus-IS-F-Part-1-We-Test-the-KN-Typhoon-High-Flow-Air-Intake.aspx

They also backed up the result months down the line & no power loss was found either.

I have an Injen intake & love it. Not a huge increase, but I could feel it (appreciate the sound too). Suspect the metal pipes would heat up faster than the silicon ones, which would probably have an affected during a prolonged track session where heat becomes more of an issue.

[Sparky]

Hrmmm.. From what i have read (not experienced) losing the 2 stage intake, which is essentially what happens with unsealed intakes such as the K&N and Injen, results in lower torque and power figures in the lower rev ranges, but an increase up top end.

After owning and driving one of these cars, i personally would rather more power down low, there is plenty up top haha!

Everyone has different goals and wants with their car, i am about drivability rather than the 5% of the time when your right up it at 6,000 rpm. Ok, 10% haha!

But youre right, there would HAVE to be an increase up top with a pod style filter, it would flow so much more.. If only we could tune these engines properly you would really see the gains.

[MR2QIK]

I noticed no loss in power anywhere in the rev range. Looking at the dyno results, ignore the numbers as they're on a US Dynojet, but it's clear there was a power increase from bottom to top.

Personally, I like that I'll have to end with bolt ons. The ISF tends to react well to them. Even if tuning were an option, I'd rather keep it well within its limits for longevity. I've been tinkering with different cars/motors for years, & doubt a tune would yield a huge amount. Not enough to justify the cost once a true solution is found & still be behind the new breed of super sedans.

[Sparky]

There's definitely no gap there in the torque and power down low, great result!

Have a look here though:

http://www.clublexus.com/forums/is-f/492945-is-f-intake-shootout-indep-dynos-for-injen-and-afe-takeda.html

Some really interesting results in there.. I wont spoil it but you should have a read..

In my experience of tuning cars (HSV, Holden, BMW) the bolt ons line you up for the tune. A tune on a stock car has some good results, but a tune on a car with a non-restrictive exhaust and intake etc get GREAT results! But you are right, the best thing about this car is its reliability, and would not want to mess with that at all!

[MR2QIK]

Yep, I've read that. There's quite a few variables there though, the ECU adaptation, large delay between runs, different dynos & conditions obviously. I also think he's comparing against a stock intake with the charcoal removed, so it's not actually stock with simple panel change. I think the difference between modded stock & Injen (which I'd guess is about the same as a K&N) are about the same & a gain.

The MotoIQ test was actually more controlled in comparison. Same car, dyno & day. Back to back, results averaged out to the conservative side & backed up at a later date. Textbook to be honest.

My background is playing with forced induction (I also own a single turbo built S8 FD RX7 & 350rwkw+ MR2 turbo on pump fuel). The IS-F motor is simply a high compression, newish tech 5.0L naturally aspirated V8. I'd bet money if it can be done, it'd sit around about a 10% power increase, which is pretty much inline with other relatively highish strung all-motors. About equal to headers. Not bad, but not that impressive $ per kw. Compared to the upgrades for the new breed of turbocharged supersedans (new C63, F80), their gains will be far more substantial. What I would be interested in though, would be a proper ECU solution, true head porting, camshaft & flex sensor fuel upgrades (if it'll ever be possible & tested). That won't be cheap, but it would be rather nice.