# throttle body size?!?!



## 04Black Goat (Dec 5, 2009)

Can anyone tell me the factory size mm throttle body that comes on a 04 gto thanks


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## GM4life (Mar 18, 2007)

75mm. People will say 78mm but its not, I mic'd it at 75mm.


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## 04Black Goat (Dec 5, 2009)

Thanks And the reason y I ask is because I was thinking on just getting it ported do you Sugest this or something elce?


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## QUIKSLVR04GOAT (Nov 24, 2008)

This is a great question. I was thinking about this the other night... haha

What are the advantages of port and polishing it VS. buying a larger MM throttle body? could you port to whatever MM you want? or is it limited to so much (MM).


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## svede1212 (Nov 1, 2005)

I'd go for a bigger TB like a 80mm or 85mm and port the intake but they may require a retune to work the best.


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## GM4life (Mar 18, 2007)

crzygoat said:


> Thanks And the reason y I ask is because I was thinking on just getting it ported do you Sugest this or something elce?





QUIKSLVR04GOAT said:


> This is a great question. I was thinking about this the other night... haha
> 
> What are the advantages of port and polishing it VS. buying a larger MM throttle body? could you port to whatever MM you want? or is it limited to so much (MM).


I wouldn't waste my time P&P a TB. I P&P my 04 TB myself and made no differance in throttle response. I've heard from a expericanced tuner that you may or may not gain power from them. If you do its a small amount. He done one himself. I later went with a Performace Products 80mm TB and that made the differance, via HPTuners. Go with a larger TB before putting money into P&P the stocker. You can't go too deep on the 04 TB because you start getting into the waterjackets, and some areas are thinner than others. If you want to go ahead and do it yourself like I did go ahead, its only time.


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## Poncho Dan (Jun 30, 2009)

GM4life said:


> I wouldn't waste my time P&P a TB. I P&P my 04 TB myself and made no differance in throttle response. I've heard from a expericanced tuner that you may or may not gain power from them. If you do its a small amount. He done one himself. I later went with a Performace Products 80mm TB and that made the differance, via HPTuners. Go with a larger TB before putting money into P&P the stocker. You can't go too deep on the 04 TB because you start getting into the waterjackets, and some areas are thinner than others. If you want to go ahead and do it yourself like I did go ahead, its only time.


When I installed Svede's intake the other day I was shocked to see these ventury-style raised areas in front of the butterfly. My guess is hogging those out smooth would help airflow a little for a "free" mod.


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## GM4life (Mar 18, 2007)

Poncho Dan said:


> When I installed Svede's intake the other day I was shocked to see these *ventury-style raised areas in front of the butterfly*. My guess is hogging those out smooth would help airflow a little for a "free" mod.


That was put there for a reason. I can't remember but it had to do with traction control, low speed control, something like that. When you go with larger TB it make the car more responsive and sinsitive. One of the reasons why GM went with the fly-by wire.


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