I plan on taking on a 2jz-gte swap in a lexus sc300. I would like to upgrade the stock turbos to t3 based turbos while keeping the sequential setup. so to acheive this I have no choice but to keep the stock cast iron manifold, it uses a proprietary design (just like how dsm uses their own flanges) is there anyway possible for me to chop off the flange and bond a t3 flange to it? I know in general you dont cut and reweld cast iron but I know there are so many differnt bonding and welding processes so figure I would just ask.

 

for the sake of durability and design in general i would recommend fabbing an adaptor flange. stock on one end - T3 on the other. it keeps it mechanical and you can change your mind later on if need be.
it is possible to weld cast but not recommended. the integrity of a cast part is specific to its form, so changing that can create new problems in new places. the piece becomes "un balanced" and its never the same.
sometimes it goes without a problem, other times its one thing after another -

 

I have some cast iron filler rod, but doing that would be tough.

 

I have welded cast iron with a mig before, and it has held up to this day, but im not sure what the heat of the exhaust will do to it. I welded a stock down pipe and it hasnt had any problems but something on the end of a turbo manifold i would just make an adaptor plate. good luck
-Drew

 

To properly weld cast, you need to get it red hot with a torch then weld it. I have done it many times with a mig before. Get it really hot, then run the welder really hot with low wire to sink it in. I have done this to fix old manifolds and cracks. I cannot say it is something I would suggest holding up a couple nice new turbos though.

I like the adapter plate idea alot better.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Electron_LS-Vtec &raquo;</TD></TR><TR><TD CLASS="quote">I have welded cast iron with a mig before, and it has held up to this day, but im not sure what the heat of the exhaust will do to it. I welded a stock down pipe and it hasnt had any problems but something on the end of a turbo manifold i would just make an adaptor plate. good luck
-Drew </TD></TR></TABLE>

The adpator plate idea sounds good.

 

I have also welded cast iron with a mig and tig using stainless rod and it has held up fine as far as i know