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Is F Aftermarket Performance Exhaust?


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these performace cars already come with a good tuned exhast systems for best torque and high speed acceleration so why waste money replacing something thats already there??

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Does anyone in the UK make an aftermarket performance exhaust for the IS F?

Has anyone ever fitted an aftermarket performance exhaust?

There will be NO alternative exhaust systems that will make even the slightest detectable or measurable diference to ISF performance - the OEM system breathes much more than adequately. Another system could affect the noise it makes, but that is all.
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thought so! most of these modern performance cars already come supped up with high tech filters exhaust and ecu's which work so effectively in deliverying the power and torque so aftermarket wouldnt really unleash another 50bhp to what is already there. and people also forget back pressure and exhaust gasses helps accelerate the car in low to mid speeds and by removing these and replacing with a straight through exhast mite just help high speed acceleration but will cause the car to be very gutless on low to mid speeds cus of lack of back pressure and exhaust gasses on the OEM system.

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thought so! most of these modern performance cars already come supped up with high tech filters exhaust and ecu's which work so effectively in deliverying the power and torque so aftermarket wouldnt really unleash another 50bhp to what is already there. and people also forget back pressure and exhaust gasses helps accelerate the car in low to mid speeds and by removing these and replacing with a straight through exhast mite just help high speed acceleration but will cause the car to be very gutless on low to mid speeds cus of lack of back pressure and exhaust gasses on the OEM system.

sorry i meant it will cause the car to be very gutless on low to mid speeds cus of lack of back pressure and exhaust gasses on the staright through aftermarket systems.

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Does anyone in the UK make an aftermarket performance exhaust for the IS F?

Has anyone ever fitted an aftermarket performance exhaust?

Due to the low numbers of IS-F in the UK it's doubtful if anyone would bother to design, let alone market an alternative exhaust system. You probably could get a specialist to manufacture one, but doubt whether it would be worth the expense.

I know there have been systems developed in Japan, Germany and the USA. All have reported minor system gains, some of which have been backed up with dyno reports. The only system that appears to have been manufactured in any quantity is that developed by 'Joe Z' in the USA and marketed by Carson Toyota. The system is alleged to provide an extra 20 bhp at the wheels, but I believe that's mainly due to the fact that the system tested didn't have the catalytic converters fitted and the system isn't supplied with any. It's also far too loud for road use and many owners in the USA have advertised them for sale after initially fitting them because of the excessive noise. Nice looking stainless system though. http://l-tunedparts....roduct/?id=3010

A Japanese tuning company also do one that looks more like a musical instrument. http://vipautosalon....-exhaust-system

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Anyone got any data or think it might be worth just adding decat pipes?

Then it will be an MOT fail.

Not if you;ve got a "friendly" MOT tester!

Or just refit them

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leave the engine and cats alone mate.. ISF's are not slow cars and have enough power and grunt to challenge your typical V8's to V6 twin turbo performance cars from Germany. to paint a picture of how good this stock engine is.... Lexus LFA reaches quater mile in 11 seconds, Porsche 911 GT2 reaches quater mile in 11.4 seconds, Nissan GTR reaches a quater mile in 11.2 seconds, BMW M5 reaches quater mile in around 12 seconds.

ISF reaches a quater mile in around 13 seconds which is just two seconds shy of LFA and 911 GT2 that cost over £100,000.

Simple to get the best out of this engine run it on good oil i.e Mobil 1 or Castrol, move the car on some good performance tires(Pirellis, Bridgestones, Yokohamas) with good PSI setting, use good high performance fuels like shell 99RON or Esso 97 RON and make sure its breathing nice with a good panel air filter to feed those 32 Titanuim dual VVTiE valves with clean oxygen...and trust me cars the ISF was designed to challenge will have a tough time getting away from your sights if not watching the L badge from behind you :geek: .. though I dont own an F my IS300 surprises a lot of cocky BMW, Audi, Mercedes and even Porsche drivers when the engine is in form..and I have not tampered with any thing under the bonnett!!!

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leave the engine and cats alone mate.. ISF's are not slow cars and have enough power and grunt to challenge your typical V8's to V6 twin turbo performance cars from Germany. to paint a picture of how good this stock engine is.... Lexus LFA reaches quater mile in 11 seconds, Porsche 911 GT2 reaches quater mile in 11.4 seconds, Nissan GTR reaches a quater mile in 11.2 seconds, BMW M5 reaches quater mile in around 12 seconds.

ISF reaches a quater mile in around 13 seconds which is just two seconds shy of LFA and 911 GT2 that cost over £100,000.

2 seconds over a quarter mile is a HUGE gap!!!

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Yes but you still geeting more bang for your buck LFA cost around £300,000 Porsche GT2 around £150,000. and to be honest ISF's true challengers are C63, M3, M5, Audi RS4, RS6 and those cars do around 12's to 13's quater mile so its level with them performance wise. LFA and GT2 are slightly above them hence thier price tag but then again with a good driver beihnd the wheels of an ISF the car can close that gap around a track.

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Just supposing there was an exhaust system complete with decat that actually gave a genuine validated 20 BHP more. Firstly, you would have a job detecting any change in performance from such a modest amount in 417 BHP. Secondly, in terms of the ISF power output, 20-50 BHP is the sort of difference you should expect from from normal daily or seasonal changes in air temperature, humidity, air density (usually through altitude), variation in fuel at the pumps and the repeatability errors of rolling roads etc.

Then, supposing you could ease the power up by 100 BHP or more by some means like a supercharger. The losses through tyre-grip (or rather lack of it) already mean that the car goes slower than the wheel revs would suggest when the power is laid down and especially at the top end of the speed range; so without some tyre/suspension enhancements to improve this, a big proportion of any advantage will just be lost.

Basically, there is not a lot that minor tweaks & so-called performance mods can achieve because Lexus has already done all this easy stuff. Although no supercar, the ISF is still within the range of cars where a hell of a lot more power is needed to make quite a small difference to actual performance.

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There aren't very many mods for the IS-F, there are a few though including exhausts but would require importing. The US are far more into modding their cars so if you are after information this is where you will find it:

http://www.clublexus.com/forums/is-f-200/

On the subject of improving the performance, one of the biggest gains may well be getting the latest MY. If you look at the reviews over the years the ISF started out as a very close car to the M3 but was beaten around a track, this was greatly improved with MY2010 LSD being added which closed the gap however the latest changes to the suspension have improved even further.

http://lexusenthusiast.com/2011/01/02/2011-lexus-is-f-competes-in-car-drivers-lightning-lap/

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There aren't very many mods for the IS-F, there are a few though including exhausts but would require importing. The US are far more into modding their cars so if you are after information this is where you will find it:

http://www.clublexus...orums/is-f-200/

On the subject of improving the performance, one of the biggest gains may well be getting the latest MY. If you look at the reviews over the years the ISF started out as a very close car to the M3 but was beaten around a track, this was greatly improved with MY2010 LSD being added which closed the gap however the latest changes to the suspension have improved even further.

http://lexusenthusia...-lightning-lap/

Does "MY" stand for "Model Year"?

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Does "MY" stand for "Model Year"?

Yes, also if you are after quarter mile times they have a thread showing times and what people modded to get them, including some Nitrous lol

http://www.clublexus.com/forums/is-f/410966-official-is-f-drag-time-dyno-time-performance-thread.html

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There aren't very many mods for the IS-F, there are a few though including exhausts but would require importing. The US are far more into modding their cars so if you are after information this is where you will find it:

http://www.clublexus...orums/is-f-200/

On the subject of improving the performance, one of the biggest gains may well be getting the latest MY. If you look at the reviews over the years the ISF started out as a very close car to the M3 but was beaten around a track, this was greatly improved with MY2010 LSD being added which closed the gap however the latest changes to the suspension have improved even further.

http://lexusenthusia...-lightning-lap/

Does "MY" stand for "Model Year"?

MY = Model Year & not year of registration. MY2009 does not exist in the UK.

The Thorssen LSD works by limiting the amount of rotational "slip" between the rear wheels before power is transferred to the wheel still gripping. The original "electronic" LSD works by braking a rear wheel rotating faster than the other one, and normal differential action then shifts power to the slower-rotating, gripping side.

As the figures show, for track use the mechanical LSD gives better results which is a plus. The only downside is that the mechanical LSD inherently gives comparatively greater tyre wear when it is brought into play. For normal road use, it is dubious that there will be much of a difference of any sort between either type.

What is probably more important is that the latest suspension changes hold the rear wheels slightly better to the road & mean a small reduction in inherent differential rear-wheel slip; so that any type of LSD will potentially have less to do - plus the ride comfort is improved (although it is fair to say that most ISF drivers find the original version's ride comfortable enough).

In respect of LSDs & suspensions changes, the choice depends on your priorities for the ISF - as a track-car, road-car or a mixture of both - and the depth of your wallet.

All ISFs are good and a little bit rare (have never seen another one on the road since April 2008) - enjoy. Rarest ISFs in UK are Ultrasonic Blue with white leather introduced by "popular" demand & have proved as saleable as men's suits in the same colours.

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Rarest ISFs in UK are Ultrasonic Blue with white leather introduced by "popular" demand & have proved as saleable as men's suits in the same colours.

Must keep an eye out for a matching suit :P

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so looks like the originaI ISF's slower time around the track compared to BMW M3/M5 was its tire and suspension setup and with these put right in the latest models with introduction of Torsen LSD cured it. so that explains sometimes to get a quicker time from a car is not all about aftermarket exhaust and decats but with a good car balance and tire grip can yeild a lot of time.

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so looks like the originaI ISF's slower time around the track compared to BMW M3/M5 was its tire and suspension setup and with these put right in the latest models with introduction of Torsen LSD cured it. so that explains sometimes to get a quicker time from a car is not all about aftermarket exhaust and decats but with a good car balance and tire grip can yeild a lot of time.

I understand where your coming from, one of my best mods to my old Evo was changing from brembo brakes to Ap's.

I shaved several seconds off a lap time around Castle Combe with this mod!

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  • 1 month later...

I've heard the IS-Fs exhaust is very restrictive so getting the JoeZ decat exhaust system will give sufficient power gains. In terms of straight line performance and sound and you'll easily be level with the C63.

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So........anyone know where can get JoeZ decat exhaust system for isF in UK?

I suspect that statements that the ISF's exhaust system is restrictive are just rumours from the aftermarket fuelled by the fact that the ISF does not make a lot of noise - particularly from the US where legislation to prevent exaggerated claims for products is very lax.

Of all the things that Lexus could have done to improve performance, a non-restricting exhaust is at the top of the list because it is easy-peasy, costs virtually nothing and is blindingly obvious. So they would have done it. In addition it is now routine and very straightforward to produce Cats that offer no detectable restriction (unless you are burning a frightening amount of oil) so that a decat system is simply pointless.

Stainless steel could possibly offer a longer life although the OEM system which is made from a form of Austenitic steel which already has an expected life nearly as long as the car's.

That said, the ISF's exhaust-note may strike people as too subdued and aftermarket systems could offer a richer sound. The term richer mainly applies to the aftermarket suppliers.

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