What size TB for my application?

[shootshescores]

I just purhcased an Edelbrock Performer RPM II for my stang. Check out my list of current mods. I will be adding some Trick Flow Twisted Wedge Heads, Cam, JLT Cold air kit, 30lb. injectors, Pro-M 75mm or 80mm Mass air (not sure yet), and all the other smaller accompanying stuff (fuel pump, etc,.) in the next few months.

My question is; What size Throttle Body should I run? I was thinking 70mm but would I be better off with a 65mm?

 

[enyawix]

65mm I made 300 to 320 wheel with bbk 65mm based on track times.

 

[5spd GT]

70mm.

No need for any bigger, unless you have future plans.

 

[NIKwoaC]

70mm.

No need for any bigger, unless you have future plans.

+1

Edit: Sorry, I always mean to leave more meaningful response in my posts than just "+1"... Its really not much of a reply.

ANYWAY, 70mm will work great with that intake, I think the inlet might be as big as 75mm, but for a street 302, 75mm is excess. If you ever go boost, the 70mm will work well too, but if you ever go stroker, you'll want to go with a bigger (75mm) TB.

 

[Grn92LX]

70 or 75mm. A 75mm will require port matching on the inlet with a drelem though. Had a 75mm on my street 302 as recommended by my custom cam grinder Ed Curtis, and liked it a lot!

 

[Rick 91GT]

70 or 75mm. A 75mm will require port matching on the inlet with a drelem though. Had a 75mm on my street 302 as recommended by my custom cam grinder Ed Curtis, and liked it a lot!

I agree and would say for your specific combo 70mm would be fine.

 

[5spd GT]

Ed Curtis is one of the guys to listen to, like Rick.

Ed told me that my current 65mm TB would be fine with my AFR 165, FTI cam, and Performer intake.

If anyone could post some good dyno numbers (less variables) with swapped gains, I would like to see them.

Been searching for years...

 

[Rick 91GT]

David, I picked up 3 mph and .2 by switching from a 65mm to a 75mm on my old N/A 302, this was back to back passes.

We picked up 5 hp and like 8ftlbs of tq to the tires by switching from a 75mm race (90mm opening) to a reg 75mm tb, same brand.

 

[5spd GT]

Thanks for the info Rick. I got a few questions with that.

Now, is this the ~340 RWHP car with the Systemax intake, etc.?

A MPH gain is ~roughly~ 30 bhp, right?

What brand was the 65mm and what brand was the 75mm?

Was they Systemax upper throttle body runner ported at all, or was any work done to the Systemax upper?

Also, you picked up power by getting rid of the "race" TB, and putting on the regular 75mm TB?

Thanks for the info again.

 

[Rick 91GT]

5spd GT
Thanks for the info Rick. I got a few questions with that.

Now, is this the ~340 RWHP car with the Systemax intake, etc.? Yes

A MPH gain is ~roughly~ 30 bhp, right? To be honest, it varies a good bit

What brand was the 65mm and what brand was the 75mm? Accufab

Was they Systemax upper throttle body runner ported at all, or was any work done to the Systemax upper? I had already opened it to 80mm, my custom EGR delete spacer was 80mm as well with both TB

Also, you picked up power by getting rid of the "race" TB, and putting on the regular 75mm TB? Yes, by getting rid of the RACE unit, turbulence was the only thought

Thanks for the info again. n/p

 

[5spd GT]

Cool, now from my memory, the Holley necks down to 65mm in the throttle body runner, a few inches into the intake.

 

[shootshescores]

I'm not sure which manufacturer to go with. My plan is to run a 70mm & EGR adapter. Not sure whether to go with an FRPP or an Accufab. I've never heard a bad thing about Accufab. The Accufab runs about $70 more than the FRPP. If the two are comparable than I was going to go with the FRPP and keep the $70 in my "heads, cam, and accompanying parts" savings.

Anyone have any opinions about the quality of the FRPP compared to the Accufab?

 

[Rick 91GT]

I personally find the Accufab or Holleys to be the best out...and worth every penny. I'll send you a PM

 

[The O.G.]

i think the edels are 70mm opening

id go with a 70,but if there was a good deal on a 65,75

 

[shootshescores]

i think the edels are 70mm opening

id go with a 70,but if there was a good deal on a 65,75

It is a 70mm opening on the Edelbrock Performer RPM II.

 

[shootshescores]

UPS just dropped off my Edelbrock Performer RPM II intake. Now all I have to do is pick up a TB. I think I"m going with the FRPP 70mm w/EGR. Once I get that, I'll be installing everything.

Does anyone have a link to a good walk-through for an Upper Intake install on an 89'-93' 5.0?

 

[The O.G.]

I personally find the Accufab or Holleys to be the best out...and worth every penny. I'll send you a PM

thats what i would go for

what about the eddy?

 

[NIKwoaC]

Dig it:

http://www.allfordmustangs.com/Detailed/614.shtml

Its for an Exploder intake, but its the same for anything, really.

 

[Rick 91GT]

UPS just dropped off my Edelbrock Performer RPM II intake. Now all I have to do is pick up a TB. I think I"m going with the FRPP 70mm w/EGR. Once I get that, I'll be installing everything.

Does anyone have a link to a good walk-through for an Upper Intake install on an 89'-93' 5.0?

If you've never done it before the Edelborck will have some instructions in the box....otherwise I would suggest a Haynes or Chilton manual as a reference.