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TB got my car slower

788 Views 6 Replies 5 Participants Last post by  speedytang
i have my car with a 306, stock heads ported, stock intake ported, 30pound inyectors, 75mm maff, 274HR cam. the problem is that i tried a lager TB 65mm with spacer and my car ran lot slower why? i had to put back the stock one again! lot of people i called told me to change the intake and put 70mm TB but i dont whant to spend my money and probaly my car is going to be worst!!!!
what should i do and why my car ran slower with more air i think it was going to be better because i have big inyectors.:sosad::worship:happyhapp:rolleyes:
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i have a book that dynos several popular 5.0L mods, and throttle bodies are the biggest pretender out there. On a 400 hp beast, a 65mm throttle body only gained like 3 hp over stock, a 70 was about the same as stock, and a 75mm actually made less power. I wouldnt waste my time on throttle bodies.
i bought a RPMII and 70mm TB for very cheap price 300$ all. what happens if i put it with my combination?
i plan for a 347 but not now like for february!
can i got on 12' s with my 306? what do i have to do?
You got to bottle feed it...:)
Get rid of those 30lb injectors and go with 19lb.
You don't have enough motor for 30lb injectors. You can go back with 19lb injectors and the larger throttle body and you will pick up some speed at WOT.
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