T3 to T25 manifold

[Cupra_R04]

What are the risks and how easy is it to convert a t3 flanged manifold to t25 if you know someone that could weld a t25 flange onto a manifold if the t3 flange is cut off.

Seen this done the other way around on another vw site

Thanks in advance Mark

 

[ibizacupra]

what sort of manifold? cast or tube?

 

[Cupra_R04]

Its a custom built stainless tubular manifold.

Has been on a high powered car. May get a adapter on but unsure of how good these are and if it would just be better to cut and weld on a new flange

 

[tashacupra]

Should be a simple job as it's a tube manifold, this is asuming there is no existing defects in the manifold that could cause problems, and that the design of the manifold is such that it makes the flange unweldable without majour rework.
Would also help if you know the grade of stainless the manifold is made from.

 

[ibizacupra]

it could be welded on top... the collector is clearly going to be bigger, so chopping off the flange alone may not be possible, or accessible to weld after. weld on top tho should be possible without too many dramas

got any pictures of said manifold?

 

[csd_19]

Why not change the hotside housing to a T-3 flanged one? You've got a 0.86? 0.82? on the 2871 at the moment? A 0.63 T-3 would give comparable flow to what you have just now, and would let you use the mani without cutting it up.

 

[Cupra_R04]

This is the manifold, the flange for wastegate has been removed so shall be getting one welded on once decided on wastegate - shall be paying for manifold tommorow

 

[tashacupra]

Wow that looks like its seen some heat, i take it you still need to change the flange?

 

[Cupra_R04]

was running a gt40 equivelant turbo and running 9.9 sec qtrs. Not sure on flange yet will look at cost of exhaust housing for manifold or welding on a t25 flange.

 

[tashacupra]

Sounds awsome, you should have had the turbo to go with the manifold .

Changing the flange on that manifold would be very simple as its nice and easy to see all the way round it (for welding), a custom flange shouldent cost much either, if it was say 20mm thick you could use that as a transition from the current collector size to the T25 size you require, assuming the turbo sitting say 10mm higher than what it would have is not a problem?