Ok looking at Throttle Bodies on evasive and theres so many sizes lol. To me bigger would seem better. Logicly- Larger means more air flow resulting in more power. Yet somthing tells me this isnt the case. So with that said whats the deal?
Why so many different sizes?

 

Bigger isn't better unless your engine is bigger. S2Ks respond best to 48mm and 50mm ITBs.

 

Bigger TBs are not a good mod for an NA s2k unless you have many other supporting mods and even then the gains are minimal. You would do better to spend your money elsewhere.

If you are FI, then a larger TB has greater impact.

 

Ok well Im running an F22 and Ill be swaping in my AP1 cams Berk TP and Invida V3... Intake on the way and hopfully an AEM EMS. I figured while I was doin the intake I could swap TBs. How little of gains are we talking?

 

3-5whp

 

Whoops I thought this was about ITBs for some reason. Late night foruming > me.

 

Ok i understand 3 to 5 is not much at all... BUT... which one will make three and which one will make 5? I guess im asking the therory behind itm If bigger makes more power then why offer different sizes? Isnt the point of building horse power to make the most of what you buy? Why wouldnt every one just want the biggest one?

 

if the size of the TB is that much greater then the IM then there isnt much gain,

you can only fit as much air as your IM can take, so going for the biggest one may not always be the best cause

 

i bought the 70mm SOS tb ... probably gained 2 hp tops if your NA dont waste ur time

 

Larger TB is really just for throttle response and better for cars that are on the track where such is needed. On the other hand, a throttle body is much like the ports of a cylinder head. You do want the largest volume but you want the highest velocity at the same time. So there is a balance and like everything else there are pro's and cons. If you have a lot of supporting mods and are out of things to do then yes TB is probably worth it, otherwise keep picking away at other things that net higher gains. For me I look at companies like Spoon and J's who have done the research to find proper sizing.