fivepointoh

What size throttle body shouldI go with for using the e303cam and trick flow manifold?
65mm? 70mm? 75mm?

w8less

65 or 70 whichever you perfer to say you have

gspfunk

Stock heads? Go 70 in case you upgrade your heads in the future....

2 kwik

65mm for crisp throttle response

LTnone

I'm usually an advocate for the smallest necessary TB, which in your case would be a 65. Like 2 kwik said, it's good throttle response, but also will net you a bit more power on a setup like that. However, if you're going to be getting heads sometime in the relatively near future, I'd just get a 70. It'll last you up until ~600hp, and you wouldn't have to try to sell the 65 and buy a 70. And stay away from the alphabet cams. There is better technology in the newer cams

OnyxCobra

I agree with the 70mm TB.

LTnone, dont you want bigger than a 70mm TB if you're running boost even if you're under 600hp?

LTnone

From what I've been told by a few sources, a 70 is the best way to go. It does seem high though, doesn't it?

OnyxCobra

I would probably go with a 75mm TB for boost applications, might be wrong though Idk.

Blck92GT

I thought about upgrading my TB to a 70mm unit from the current FMS 65mm when I did the hci swap, but I am glad I went the 65mm. Helps keep air velocity up and I made more hp and tq than similar combos my buddies have with 70mm throttle bodies. Bigger isnt always better