Exhaust Manifold

[AudiBama]

are they really that restrictive on our cars?

would a kit like this be worth it?

http://www.speedlifemotorsport.com/kituexmakit.html

[mxrz]

Restrictive... With what turbo?

[AudiBama]

k03s

[mxrz]

It's not really a flow restriction with the K03, it will only shift the power band slightly, without any gains.

[B6Lovin]

the k03 is the biggest restriction on your car right now as far as air flow is concerned lol.

personally i think everything in the stock system is restrictive..
turbo
exhaust manifold
SMIC
piping
intake manifold
TB
cat bolted to the back of your turbo
the rest of the stock exhaust
MAF
TIP

pretty much the ONLY good part is your airbox itself. that thing is the tits

[CyberPMG]

Looks very similar to the ones offered by ATP and 034. You'll gain about 10-15% more HP and torque under the curve. That means you may get a tiny bit in peak power and torque, but you have a little more of both as you go through the RPM range.

I have the one from 034. Had it ceramic coated prior to install. It's helped to smooth out the boost spike and holds a few more pounds of boost. I've been very pleased with it and the K04. Make sure you either get a locking flange or tack weld the bolts between the turbo and the manifold as they tend to back out on aftermarket items.

[Tgr_Clw]

pretty much the ONLY good part is your airbox itself. that thing is the tits

Well said.

[Killerteve]

Make sure you either get a locking flange or tack weld the bolts between the turbo and the manifold as they tend to back out on aftermarket items.

Another concern here...I bolted on the K04 with the hardware included(blue color) with my 034 mani I bought in the classifieds. I can't say if it is the hardware included if u where to buy it from 034, but one of the bolts was too long and bottomed out in the threads on the turbo. This caused the gasket not to seal and eventually burn up and fall apart creating a huge exhaust leak. Luckily for me the threads on the bolt stripped instead of the turbo housing so it was an easy fix but if ur using the 034 make sure to check for this.

On the performance side I've never dyno'ed my car and the mani went in with my K04 but I'm sure it's doing something to smooth the torque spike and flow better up top since the power delivery is smoother and doesn't die off as quick as the K03(of course the K04 is helping that too). Now I just need a FMIC!!

[CO AVANT]

If you are running a K03.... the intake manifold, TB, & MAF are not doing any part in restriction of your setup. Everything else B6Lovin posted is a restriction in some sort of way/shape/form. Stock intake mani small port works great for small turbo setups. You could spend $2000 on a new intake mani for a K03/k04 and gain 0 power with it. All the parts needed for an optimal system starts with how big of a turbo you want to run. It's all relative.

[B6Lovin]

If you are running a K03.... the intake manifold, TB, & MAF are not doing any part in restriction of your setup. Everything else B6Lovin posted is a restriction in some sort of way/shape/form. Stock intake mani small port works great for small turbo setups. You could spend $2000 on a new intake mani for a K03/k04 and gain 0 power with it. All the parts needed for an optimal system starts with how big of a turbo you want to run. It's all relative.

well on a k03 those probably don't matter... i guess i was just listing all the things that were a restriction for me -- and which i'm replacing with something less restrictive :)

and issam - if you're reading this... i got it today, and it looks AMAZING! can't wait to try it out

[MikTip]

The OEM exhaust manifold is designed to aid the exhaust gasses in exiting the head at high-velocity. This in turn spools the turbo up quicker.

For the smaller, K03/K04 turbo's its fine.

You can cram only so much air thru the OEM sized turbo opening at the end of the manifold, no matter how big the runners are! The bigger runners will allow the exhaust gasses to expand more, and probably slow down the exiting velocity slightly.

Those who have the larger aftermarket mainfolds, report a shift in the torque curve, of the turbo effect on the engine. Which seems to indicate the turbo spools up not a quick, as with the OEM manifold.

[CO AVANT]

I think an atp mani is overkill for k03/k04 apps. I had my oem mani ported and polished for my K04 and it free'd up some flow up top while still keeping velocity high for spool up. BTW, does anyone want to buy my ported and polished oem exhaust mani?

[MikTip]

I did the same...ported & polished my OEM exhaust manifold. Then had it Jet-Hot cerami-coated for heat reduction and corrision resistance.