JGRIFF

I have a completely standard STi7, I am considering getting the headers ported, has anybody got any observations / recommendations about the benefits, price, people capable of doing the work?

barge

got mine done at scooby sport in essex.

seems to rev up quicker

harvey

iTrader: (48)

From memory the cost was £120. Could feel no difference whatsoever.
Flywheel was to be lightened from 12kg to between 7.5 & 8kg at same time.
Subsequently had engine out to find that somehow the flywheel had regained weight to 9.2kg and I would best describe the headers as having seen a file.
Headers have now been done properly, ported to the exhaust gasket imprints/shape.
Now I can tell the job has been done & the car pulls more boost too.
Advice.Tell the company carrying out the work that you want to see the headers before refitting.
In my case that was not possible as they were 300mls away, I took them at face value and relied on what I believed at that time to be a good reputation.

JGRIFF

Dave,
Thanks for that, I'm afraid to say that your experience with Carolyn's car, falls exactly in line with my thoughts on the matter. I'm beginning to suspect that PPP will be some time in being released, and might be the only way to produce a reliable power increase for the forseeable future. I agree with your previous post that It's not going to be the detonation of my engine which allows others to gain first hand knowledge!

Dave T-S

John

Yep, let someone else do the engine destruction test work!

Decat from downpipe back is ok - mine runs 1.35 peak boost, 1.15 held.

Add downpipe, and it will spike to 1.5 bar. Many people tell me this is too much.

Up pipe, OEM downpipe and decat from d/p back = 1.5 bar again.

Replacement up pipe, and full decat from turbo back = 1.7 bar spikes

There are remedies out there - however I have only heard of one so far that claims to have cured it with restrictors only, the others are a combination of restrictors, Unichip and Dawes device.

You are then probably more expensive than a PPP, no more performance, and no warranty if it lets go.......wish Prodrive would hurry up and get it sorted

However, as Mike Wood said to me - they could rush it into production, or they could test it properly

Judging by Josh's pictures of Mike driving Prodrive's demonstrator, he is taking this seriously

Dave T-S

John

I would be very careful about this. I had the replacement turbo up pipe taken off Carolyn's car on Saturday, and replaced by the standard item. This not only cured the last bit of boost spiking to 1.5 bar (it's now back to 1.3 - 1.35), but the gasket between the manifold and up pipe had totally melted on one side - and bear in mind this is a triple layer laminated steel gasket. It may of course have been a faulty gasket, but I do not think so.

Two things:
1. There are obviously some VERY severe EGT's in this area.

2. The OEM up pipe is sleeved down by about 5mm by an internal sliding expansion joint. This is the biggest restriction in this area and there would be no point in gas flowing the manifolds as they are upstream of this. Additionally, it is clear that increased gasflow to the turbine was contributing to the boost spiking by, I believe, allowing the turbo to spool up faster.

[Edited by Dave T-S - 4/8/2002 8:59:04 AM]