Hey all, been looking for a thread on this all night but I am about to rebuild my s4 turboII block and was curious if there were any benefits to using the s5 n/a irons? If you look at the n/a rear iron the intake port is noticeably larger. I understand I'd have to port match and such. Mainly I'm trying to figure out if there would be any real benefits or if I'd easily end up over boosting without a tune.

 

Bump. Any info on this would be greatly appreciated!

 

Its not worth it. IIRC the N/A irons are much weaker than the tII, and you'd have to tune

 

Thanks a ton for your input! So essentially the wise decision is to either keep stock irons or port the stock turboII irons if a larger port were desired?

 

Bump. Previous question still stands and is unanswered^^^^^^^

 

Roatry Evolution probably knows more about this subject than anyone. Personally I would like to build a TII keg with NA irons for the fact that it'd be an easy way to get extended port area and may flow better in higher boost conditions, my theory being based on some 13+psi. Never seen first hand results on this but it may just work with great results.

 

I know my thoughts exactly! Seems like a nice way to have larger intake ports without actually porting.