Hey everyone, just looking for people with experience switching out throttle bodies to either modified stocks ones or aftermarket units and have dyno proof that they either helped or didn't. Engine builders and tuners especially, thanks in advance.

Build is a 2005 Heritage with S&S 100" kit with ported heads, (STG 2 or 3, haven't picked a porter yet), at approximately 10.5:1 with S&S 585 cams.

I'm trying to figure out if the $3-600.00 is worth the extra cost for the added HP.

Thanks,

David

 

If you get the on the intake ports over 250cfm at 28, You'll see a bit more top end HP with a TB.. Target 260 or better. The 585 lends itself to a better intake flow. There are a number of head guys here that can set you up with heads that with a better TB and the 585, will do well.

 

An aftermarket throttlebody will garner you maybe about 1 or 2 horsepower and maybe anywhere from 1 to 4 ft.-lbs. torque over the stock unit. It's a known fact that it's not a good choice for finding the extra power you're looking for unless you're into drag racing where you need to squeeze every bit out of the motor. That extra $3-600 is better spent on head work and/or exhaust.

 

A 51mm HPI would be a good choice.
1.710", or 1.800" port ID to match the head, once ported.
100"/.585 cam and a good set of heads/intake/exhaust has the capability to be a very stout piece.
Scott

 

any decent heads should flow way more than 250 @ 28",and a larger t. body with larger runners,properly matched to the headwork,will yield a lot more than 1-2 hp & 1-4 #`s of TQ.well worth the $$ on most mid-higher RPM builds

 

 

 

Thank you guys, I appreciate the information.

David

 

Already doing head work and a 2 into 1, so looking at the TB on top of that.

David

 

Few things to note.

Your desired HP should be limited by your heads not the throttle body.

It's possible to have too much intake flow and too much cam duration. Especially if the exhaust can't keep up.

If the heads don't flow, a bigger TB won't help.