I have heard to use the biggest like a 70mm but some say that's over kill..... I should use 68mm I'm running a stock ITR one right now I dynoed 204 ttw's and I'm looking for more!
Set-up is GSR block with stock bore Pr3 pistons ITR head shaved 30thou slight ported head sk2 stage 2 cams DC header ITR intake mani with ITR T.B I have a 2 1/4 crush bent exhaust so I know I need a exhaust and a bigger T.B and I want to switch to obd1. Any help would be great. Thanks Rob

 

i say keep the the 62mm t/b and save and get a better header and a better cat back anything 2.5" should do

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by DIFFUT’S INC. &raquo;</TD></TR><TR><TD CLASS="quote">i say keep the the 62mm t/b and save and get a better header and a better cat back anything 2.5" should do </TD></TR></TABLE>

Well my friend has the excat same set-up but he has obd1 ecu and a Hy-tech and made 207 ttw's sorry but I'm not spending that much for a header to get 3 hp we have 1.8's not 2.0's Rob

 

anyone else???

 

70MM tb's make power up top so if your peaking in the 8500 rpm range it would be worth it but you will lose power down low