which throttle body do i get?

[JimmyRGT]

Alright iv been puting a lot of posts here about the mods i am about to make, i just want to make sure i get everything right before i do it. You can see in my sig what iv done so far and i am about to put AFR 165's, and a Trick Flow Street Heat Intake on it. My original plan is to put a 70mm BBK TB on as well. Is this the right size or should I use a 65mm? Will the 70mm hurt my low end? The next addition after this set is a power adder so i want to keep that in mind. Throw the advice at me. Thanks.

 

[JimmyRGT]

oh yeh im also puting RR's on there and probobly a c & l 76mm intake system, if that makes any difference.

 

[Rick 91GT]

I'd go 70mm or even a 75mm (if you plan on a supercharger for your power adder, or plan more mods down the road, why waste money?) it will not hurt the low end at all, despite what many say.

I ran a 75mm Accufab on my NA low compression 302, I had no issue with low end and the combo was geared towards top end power. I picked up 2mph and a little over .2 @ the strip on back to back passes over my 65mm Accufab.

Although I had good results with the 76mm C&L, I'd suggest going to the 80mm Pro-M shorty, it will be better in the long run

 

[86Cobra]

I agree with Rick.

 

[Michael Yount]

The diameter of the throttle body will have no impact on bottom end positive or negative. 65mm is plenty big for most any streetable naturally aspirated 302. If you're gonna run boost, or a really high revving/powerful combo (up over 400HP) you may want to move up in size -- but the larger size won't hurt a naturally aspirated engine. On a milder set up, the larger throttle body may have an impact on drivability/throttle response. The larger the throttle blade is, the less change in throttle position is required to admit more air. What that sometimes means is that with a very large throttle body on a milder set up, it's more difficult to smoothly modulate small changes in throttle opening - can show up as some jerkiness in response to small throttle inputs. But it doesn't always happen. My suggestion would be to get the smallest throttle body available that will meet your engine's flow needs. The 65mm will be plenty according to your plans for the motor described above unless you put the power adder on, and you virtually never hear anyone complain about their Accufab or Ford Racing throttle bodies. Most all of the other brands you'll hear complaints about from time to time.

 

[93 teal terror]

I just recently put a 70mm edelbrock tb and spacer on my car with stock heads, cam, and intake. I have 2:73 gears and can tell a slight drop off in low end power. Not very much but noticable. I have future plans for h/c/i and or a supercharger, so i felt it was best to go with a 70mm. Although even with h/c/i and a supercharger a 65mm would have probably been enough

 

[JimmyRGT]

Hmmmm well the next mods after this are probobly forged pistons and NO2 although im not sure about that. Does that have any effect on what i should get?

 

[Grn92LX]

75mm TB and I like accufab TB's.

 

[cardudeusa]

Definatley 70-75 MM, only go with accufab they are top notch.