Thick gasket

agreed if you want to run higher boost it's probably necessary for a std 8v head. get a crosflow head though and you won't have the same problems and can run with a higher CR. IIRC the TT conversion struggles with fuelling also which doesn't help
tt

 

Strugles with fueling........... don;t know what gives you this idea......... nice and rich in the mid range, nice and weak at the top end, fine at the bottom - sounds just ripe for a big bang to me !! Saab Turbo metering head in theory sorts the fueling out. got a V-SAM Pro to drop on to give it a final tweak - if only we could have the good old days of proper grade fuel things would be fine !!

 

try and shield the plenum from as much heat as possible from teh exh manifold and turbo - that's one half of the problem - charge heating
tt

 

Yep, thought about exhaust wrap to help, but another one of those jobs to get round to

 

Ceramic exhaust paint, you can get good stuff that is fine on exhaust manifolds and downpipes. Jeg's has been suggested as a quality make.

 

I'll let you nkow soon about my VR6 with a thicker head gasket to lower compression for the turbo when I've driven it that is...