What TB for my combo?

[Davin]

I currently have a 70mm that I was using before the 347 build. Unfortunatly, I had drilled a hole in the TB plate as a "trick" someone suggested for improving idle. I think its causing some problems. Anyway I was thinking of going smaller with the FRPP 65mm but wondered if this was too small. What do you guys think. Also, if its not in my sig, my exhaust is 2.5" still and it is a street/non-track car. TX

 

[Grn92LX]

If you are buying a new tb, go 75mm and port match the inlet on that rpm II to 75mm. Only reason to use a 65mm on that combo is if you already had it laying around and you were out of cash for the proper sized 75mm or if you purposly wanted to make the car slower.

 

[94gts]

90mm

gotta go with mike on this one, ive listened to him a few times

 

[MustangGT95]

Think a 75mm would be to big for a car with my mods? Plus a new intake of course. I can get a killer deal on one so I may snag it up.

 

[Grn92LX]

Think a 75mm would be to big for a car with my mods? Plus a new intake of course. I can get a killer deal on one so I may snag it up.

75mm will be fine. Been there/done that.

 

[ProKiller]

75mm...

 

[final5-0]

I currently have a 70mm that I was using before the 347 build. Unfortunatly, I had drilled a hole in the TB plate as a "trick" someone suggested for improving idle. I think its causing some problems. Anyway I was thinking of going smaller with the FRPP 65mm but wondered if this was too small. What do you guys think. Also, if its not in my sig, my exhaust is 2.5" still and it is a street/non-track car. TX

You could always JB Weld the hole and see if things get better

Grady

 

[Black95GTS]

I currently have a 70mm that I was using before the 347 build. Unfortunatly, I had drilled a hole in the TB plate as a "trick" someone suggested for improving idle. I think its causing some problems. Anyway I was thinking of going smaller with the FRPP 65mm but wondered if this was too small. What do you guys think. Also, if its not in my sig, my exhaust is 2.5" still and it is a street/non-track car. TX

That trick does work... on a Fox body A9L!! I've actually seen it happen. My friend did that in high school and I bagged on him while he was drilling... well he dropped it in and I ate some crow.

The Fox computer is RPM based, ours is air flow based. By drilling a hole you are creating unmetered airflow which will mess with your computer.

Use a 75mm throttle body.

Adam

 

[Davin]

Thanks for all the replies fellas, I must admit that I am a bit intimidated with going to 75mm. I remember when I went to 70mm (still 302) many said that this was too big and that there would be better throttle response with a 65mm b/c of higher velocity/better fuel mix. I guess the limiting factor is still the intake runner and not the TB anyway. I will take this advise. What brand is the best available?