Tapered or straight ITB's???

[Jeff Alton]

Okay, ordering my Jenvey's for the 3.4 and have a question or two....

Is 48 the correct size? Should I get tapered ones or straight ones?

How much difference in flow between the two?

Thanks

[Porschekid962]

Hey Jeff, I went with taper bore Jenveys. Also when ordering be sure to ask or specify the base manifold diameter. We got setup with 48mm taper bore and that tapers all the way down to 40.5mm at the base of the manifold where it mates to the head. That is the larger of the two manifold options, the other necks all the way down to 38mm. Its not so much the flow difference between the two but the acceleration of flow as it moves towards the head. For an NA motor I think a taper bore is the way for performance but going with a straight bore on a street motor might not make that much of a difference. Are you getting them through Mike by chance?

[Jeff Alton]

Thanks, yep going through Mike, we do a fair amount of business back and forth between our companies. He is good guy, so is Souk.

Cheers