To those who ported your stock exhaust manifold

[nism014]

I tried searching for the last 20 minutes and finally gave up looking.

I remember some of you guys discussing how some of you machined your stock exhaust manifold but I couldn't find the discussion related to this.

How's the power gain for porting the stock SR20DET exhaust manifold?

specs of bore, etc...

[bxsvx]

Bringing this thread back. Anyone have answers to the above questions? I am also curious? Pics, info would be greatly appreciated. Thanks

[usdm180sx]

iirc codyace on here extrude honed his stock mani and got 400whp w/supporting mods...

[bejota180sx]

iirc codyace on here extrude honed his stock mani and got 400whp w/supporting mods...
if im not mistaken, it's been a while since i last cheked codyace thread but he had made something like 397whp with honed extrude manifold with gt2871, no cams, stock intake manifold and pretty much the rest like front mount and exhaust... the best part is you know it won't crack (at least not as easy as some SS tend to...) and you keep the PS and AC system with no modification which some manifold don't tend to be so friendly with... if i misgave any information sorry (i've been working on a BIO report all day long so my brain ain't firing right...) i'll check tomorrow to see if i can find more info, but search for codyace's thread it has useful info...

[mattsil80wis]

if im not mistaken, it's been a while since i last cheked codyace thread but he had made something like 397whp with honed extrude manifold with gt2871, no cams, stock intake manifold and pretty much the rest like front mount and exhaust... the best part is you know it won't crack (at least not as easy as some SS tend to...) and you keep the PS and AC system with no modification which some manifold don't tend to be so friendly with... if i misgave any information sorry (i've been working on a BIO report all day long so my brain ain't firing right...) i'll check tomorrow to see if i can find more info, but search for codyace's thread it has useful info...

There is a lot of wrong in this statement

Cody's set up is JWT s3 cams, Greddy IM, gt2871r .64 he made 415whp
He only made 396 when he put in the JWT c1 cams, but now he's back to the s3 cams

without cams and an intake manifold the gt2871r will most likely never see over 320whp

Being that the manifold is cast iron it shouldn't crack, and will hold up better to the heat cycles that it goes through.

Extrude honed search for that and you will find the company

[moses]

This tell you everything
http://zilvia.net/f/sale-items/201360-group-buy-extrude-honing.html

[ShadowDrifter]

For thoes of you who want ported stock manifolds I am doing them turn around is less then a week and if anyone wants pics please let me know I have gotten them very smooth and VERY clean. ALL ports are gasket mached and runners best that can be done. So if anyone is instrested let me know.