B20 ITB 12,2:1

[Gaskleppie]

Build B20 block B18c6 head JE 12,2:1 pistons Toda c cams Jenvey 48mm ITB's Unknown exhaust manifold 2,25inch catback Fuel was euro ron 98 with a bit of octane booster. What do you guys think? Are the 48mm ITB's too small???

[fah]

i would try a 2,5 inch catback

[marshall.hagen]

Exhaust piping is too small. At least a true 2.5\", I would suggest a 70mm (skunk2 or T1R) or even 3\". The 48mm ITB's are fine, especially if they are the Jenvey's with the 90 or 100mm stacks. He would also gain huge amounts of mid and low end power with a better cam like a Skunk2 Pro2 or Pro3.

[ge0ne]

it depends. If it is an everyday car i would stick with 50 or even 52mm. If it is a street race car i would go 55, and if it is a drag car i would definately stick with 55 and opt for 58s.

[marshall.hagen]

That statement would be true if he were using TWM's, but the Jenvey 48mm's with 100mm stacks I have seen produce up to 260whp on a dynojet. I still think his resources would be better spent on an exhaust and cam change