Fast 78/78

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Feb 9, 2011 | 08:42 PM

mikemunoz

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From: Harlingen, Tx

Fast 78/78

I got a fast 78 intake with a fast 78 tb, was wondering if i can put a 90mm tb on my fast 78 intake, would it fit. need info asap thanks

Feb 9, 2011 | 08:44 PM

98silvermaro

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From: Norcross, GA

If its a 3 bolt TB it will fit BUT its not going to help you any because of the 78mm intake

Feb 9, 2011 | 08:49 PM

mikemunoz

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From: Harlingen, Tx

i read that porting the opening and just putting a 90mm tb works but just making sure. plus also read porting the runners and opening and you got yourself a basic 90mm intake. an i wrong

Feb 9, 2011 | 09:05 PM

98silvermaro

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From: Norcross, GA

you can port it out some but it wont port out to a 90mm opening and the runners wont open up that much either

Feb 10, 2011 | 06:46 AM

garygnu

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most 90 mm TB I know of are 4 bolt design .

Feb 10, 2011 | 08:16 AM

wicknewman

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From: Schertz, TX

The largest a FAST 78 opening can be ported is 85mm. Any larger and you will not have area left for a gasket sealing surface between the TB and intake. Even when ported to the 85mm size you need to do some minor mods to get the gasket to seal properly. The 78 is identical to 90 in runner design and internal area. Only difference between the 78 and 90 is the opening.