Fast intake
#1
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How can you tell the difference between the 78mm Fast intake and the 90mm fast intake?
Also on the TB do you measure the front of the TB to see it's size?
I bought a "what is supposed to be" a 90mm intake and TB yesterday.
The TB was a Nick Willams for a Vette. I have a Fast 90 siting at my house off a Z28 and the front of the Nick Willams fits in the front of the fast.
I also have a stock TB and there isn't a huge amount of difference between the 2.
I am guessing I got a 78mm when I was supposed to get a 90.
Thanks
Also on the TB do you measure the front of the TB to see it's size?
I bought a "what is supposed to be" a 90mm intake and TB yesterday.
The TB was a Nick Willams for a Vette. I have a Fast 90 siting at my house off a Z28 and the front of the Nick Willams fits in the front of the fast.
I also have a stock TB and there isn't a huge amount of difference between the 2.
I am guessing I got a 78mm when I was supposed to get a 90.
Thanks
#2
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If the intake has 5 holes to mount the throttle body then it is a 90mm. If it only has 3 then it is a 78mm. The throttle body size is measured by the diameter of the blade. You can't go by the opening on the front of the throttle body. I made mine 4" so the stock adapters work. Fast and TPIS use a 4 1/4" opening and require different adapters.