Stock Turbo Flange
 

Quick question - what is the flange size on the stock turbo?

My exhaust manifold cracked and I figured I'd put a little bit more money into it and upgrade, but I gotta know a bit more before I do anything-

Thanks!

S5 or S4
for S4
T4 flange, but is not completely a T4 flange.
Because the T4 flange is more rectangular than the S4 manifold flange. The S4 is slightly odd shape and bolt pattern is a bit different It wont bolt rite on to the stock turbo.

for S5
T4 flange will fit bolt rite on to the stock turbo

Those flanges are proprietary.

why upgrade the manifold and not the turbo? just get another stocker that isnt cracked for like $50...unless you plan on getting a new turbo anyways. the only replacement manifolds with the stock footprint that i've seen are thoes POS ebay manifolds which can't be much/any better than stock.

NO, neither are T4 flanged or even T4 sized or even close. Their closer to a T3 in flow, but aren't. As J-Rat said, the TII turbo flanges are proprietary and match nothing but their own manifolds and turbos. Theres those ebay junker replacements, but I'm not sure of the positioning of the turbo using those manifolds. It might not mate up to a exhaust system witout modding the DP. Either just get a good used replacement of go all out and build you a full T4 turbo system (be prepaired to spend a few grand).

~Mike.................

Jon,

If you like I'm having some RB25 flanges cut and I could have one watter jetted out for you. It would be mild steel however.