Throttle Body Question

[AraileyV06]

Are there any aftermarket throttle bodies available for our cars? If not, how much does it cost to port and polish the stock TB? [img]graemlins/burnout.gif[/img]

[speedy-v6-camaro]

No one makes aftermarket 3.8 TBs. You can P&P your own if you are brave enough. Someone has a guide on how to do it.

[tuffluk55]

I'm getting mine done for 75 bucks, but I'm not sure if it is more than that or not, cuz my friend is doing it for me.

[strange_trp]

port ok. polish probably not... most recent studies by the us govt noless has shown that rough surfaces provide more velocity due to a series of mini vortices. kind of like a million drafting effects. i've seen flow numbers for cyl heads and the ones ported but not smoothed flowed much more air.

[Ian]

no no, polished intakes are good to flow the air, but with intakes and heads, you cant polish them TOO much. there needs to be some roughness in the ports to atomize the A/F mixture.

if the ports are too smooth, the fuel wont mix well w/ the air, and you'll therefore lose power.

TB would be OK to polish up. no A/F mixing going on there.

[ November 14, 2003: Message edited by: Ian ]</p>

[strange_trp]

still, airflow is airflow.
if rougher (to an extent) flows with more velocity on a bench it really does not matter where it is. a slightly rough texture will flow with more velocity. more velocity means more oxygen coming in, which means the pcm can deliver more fuel without going out of range rich.

bench tests do not account for relative location. they just measure the mass and velocity of air flowed through a passage. too smooth = too slo.