I have a GE intake manifold on my engine (H22A, 2414 cc's, 13.5:1 compression, etc). We measured the opening on the manifold, it's about 74 mm. The throttle body I have now is 65 mm. I was told I needed a larger throttle body or the throttle body gasket will get sucked into the engine due to the difference in the hole size of the manifold vs the size of the throttle body.

I think he's (the builder) is full of it and is just trying to sell me a larger throttle body. He wants me to get a 70 mm throttle body. I think that would be overkill.

If you do think I should get a better throttle body, what brand would you recommend these days? I've not followed the "scene" for a long time and no longer keep track of what's good and what's not.

Thanks.

 

Your manifold is overkill.

 

why would you use a huge manifold like that then choke it with a dinky throttle body?

 

Ditch the GE manifold. Unless you're making over 700WHP.(that's a ballpark number) its overkill.

 

Its too late now. Its bought and paid for and on the motor. I should have gone with a rosko euro-r manifold, but I didn't.

With that said, I would appreciate an answer to my throttlebody questions.

 

Do a reverse gasket match. Place the gasket on intake and trim away excess gasket. Use a new blade to get a clean trim. As far as tb being too small or not or choking the mani I'm not sure of that.

 

i had a good MAP numbers with 70mm on b18
now my 64mm works good before 7500rpm on b16NA. and will be replaced with 67mm
builder not kidding

 

You got an answer. The TB you want to use is too small. Poor planning sucks.

 

Thanks to Urus and boostedshoe for your responses.