racingminds

Okiez so I have pondered for a long time as to whether a 3" exhaust system will benefit NA S2K applications. And we set out to see if we should run a custom dedicated track-ONLY exhaust on our S2K. We therefore decided to fabricate a 3" headerback exhaust system out of 1.2mm thick stainless steel, which is thinner than standard SS (1.5mm). We have been running the J's Racing TwinFX Ti all along, with a custom testpipe on track, reason being gains have been documented to be decent, and it's 1 of only 2 exhaust systems being approved for road use here in Singapore. The other approved system is a Mugen twin system, that is partial SS partial Ti. Fabricating a 3" headerback Ti system would cost quite a bit so we decided to keep weight down by ordering 1.2mm SS. The weight of the 3" circuit exhaust came out to be identical or slightly lighter than the J's Twin Ti, but of course it doesn't have a muffler and it's a single exit.

Pics are attached below along with some videos. WARNING: It is rather LOUD. The last video is a sound comparison with the J's Racing system on the car on the same day. We actually tested both exhaust systems back to back with my tuner on the dyno as power figures were low while testing the 3" and I suspected that my engine is losing power compared to previous readings when the ITBs were first done and with a fresh clutch. So I decided to test it back to back, eliminating the variable of the car's condition in the past. Honestly my tuner didn't tweak the maps much, just some slight changes to fueling. I haven't had time to print out the dynochart and scan it in, but will do so next week.

Basically, the 3" headerback circuit special made MORE power throughout the rev range on a NA F22C ITB setup. I believe there might be more gains to be harnessed if the engine wasn't a stock standard F22C and if we spent more time tweaking the maps. Down the road, we might also play around with the sizing of the pipes at various portions of the exhaust system and see if it might be more optimal. Having a muffler might be considered too cuz I dunno if this will be too loud for me to hear anything else on the circuit. We actually had to pull down the shutters of the workshop because it was simply too loud.

In a nutshell, 3" is .

PICS









VIDEOS
[media]http://www.youtube.com/watch?v=ivamgel6v4c [/media]
[media]http://www.youtube.com/watch?v=Iovsa5BBXbw [/media]
[media]http://www.youtube.com/watch?v=vp13S9J9Bbw [/media]
[media]http://www.youtube.com/watch?v=x3wgwCcdj8Q [/media]

Sinji

sounds great! how much power did it make over the j's?

car looks good!

GT Motoring

Good call sir. We are currently jigging up a 3in race exhaust for our time attack car as well. We knew gains would be had for sure though. I'm glad you had a chance to confirm it first hand as well though!

wadzii

on a mostly stock ap2 we replaced a custom straight 2.5 inch exhaust with a similar 3inch exhuast, it picked up about 10hp over the 2.5inch

EVAN&MONICA

Looks and sounds pretty mean looking forward to the comparative dyno charts

camuman

that has to be F'n loud!

fireball

thx for that info. will have to make a 3in exhaust someday now
was thinking of only running mine back from the 70mm test pipe in comparison tho

//steve\\

I think with the 2.2L motors a 3" inch will be fine. HKS has a new 75mm single exhaust coming out soon. For reference 3" is 76mm so obviously they've found it to work as well.

ap1_tot

It won't be that beneficial when used in an F20? I always thought aftermarket exhaust/Intake parts would be interchangeable between the 2 engines.

godfather2

wholly db level! congrats on numbers though