Throttle body adapters from 4500 to 4150 style are they any good ?

[waynieZ]

Hi I have just bought a Fast bank to bank EFI set up with a Victor Jr manifold and 4150 TB . ( I may switch to an XFI later. ) My motor is a world 454 sbc it has a World intake on it. I also have a Fast pn 30-7602 up to 2000 cfm TB. I think this TB is too big for my engine . I bought it a while ago wanting to use it on my World intake. Like they say a little knowledge is a dangerous thing or in this case an expensive thing.
My question is Wilson makes an adapter to use the 4150 on the 4500 intake. Will using this adapter hurt my power seeing that the plenum is bigger on the 4500 intake or will the engine even notice the difference? I would like to keep the World intake sense the world made some of the best power in the Chevy Hiperformance intake shoot out. Any help is appreciated and thanks in advance. Wayne

[LSXZ28]

Don't think it would hurt power - I've seen many of the LS guys use it the other way around - dominator TB to 4150 Vic Jr and if anything would hurt power, that way would. Now that they have a dominator Vic Jr out, they don't have to do it that way... In my opinion, you will be alright as long as the TB flows enought to support your power level...

[64duece]

You'll likely see a pretty small decrease in power when switching to the EFI from your carb'd setup. Negligable compared to what you'll gain in cold start and overall driveability. The 4150 TB should have better off idle manners than the 2000cfm 4500 flange unit. Most of them are progressive so, that helps abit. I'd bolt the 4500 on and atleast see how it responds before you adapt the 4150 on there.