Hoping to hit the 400bhp fig with supporting mods and question I have is, should I go with ported heads and a Harvey up-pipe or RCM and a Harvey pipe.
2002 STi
Thanks.

 

Id go with the ported manifold setup, the tubular manifold will probably make a little more up top at the expense of low down torque which you get from the ported setup

 

Cheers Banny.

Who supply's the ported set, would want them wrapped as well.

 

ive just ported my own and fitted a harvey pipe , having the map tweaked tomorrow . if your confident its not that difficult tbh . you can defo feel the difference i'll see what the tweak brings tomorrow .

 

Alyn at ASP is your man

 

you rang..............

 

info in this thread

https://www.scoobynet.com/trader-ann...d-headers.html

 

What are we porting here? I looked t mine when they were off and the head/manifolds are same size and quite well matched already. Both are smaller than the gasket, but then there's no point in opening up the manifold if the heads still small, would that not just slow down gas flow? I'm not saying what you have done doesn't work, I'm just curious what you have done to make a difference? Cheers

 

cant speak for others but ours are fully gas flowed to ensure optimum performance

 

I'd go with Alyn. I know his work, and he now also sells the Harvey up-pipe.

My own spools from very low revs and produces 1bar at 2800 rpm.

 

I also wondered the same. Keen to hear an answer to this.

 

I want them heat wrapped as well as I screwed it up last time. Haha.

Alyn do the headers come wrapped?

 

Harvey's used to.


TBH, it's reasonably easy to do.