View Full Version : Throttle body porting

10-13-2009, 08:24pm
Does porting and polishing ones throttle body really make a noticeable difference in power or responsiveness? I'm talking mainly about a stock 00 TB paired with a LS6 intake as well as ported 243 heads, cam, headers, blah, blah, blah.

Also, what if the intake was worked as well? And no I'm not paying close to 1K for a fast intake.:nono:


10-15-2009, 07:52am
Good question. I keep reading that part of bolt-on performance upgrades should include a larger TB, but it sure would be cheaper to port & polish for those extra ponies.

10-15-2009, 03:18pm
Technically speaking, the larger you can make the inner diameter of the TB, the more air you can push through it.
That being said, I'm not certain on the port/polish. I've done a set of aluminum heads(back in the day). But that was before bolt on, so I can't say it helped/hurt.
I'm thinking you can pick up a stock TB for cheap, P&P it, throw it on, and see if there is any change. :thumbs:

Mike Mercury
10-15-2009, 09:15pm
it's not like in the older days... when you could flip over the air cleaner lid and gain 5-7hp. If the LS1 motor is stock; porting the throttle body alone will not yield much of an inprovement.

Everything on the stock LS1 is well matched and up to the task; at stock HP levels.

Bill Curlee
10-16-2009, 05:38pm
The answer is basically YES,,,,BUT,,,,,not in a significant way. Here is what I experienced when I recently helped a buddy install headers and a VARARAM on his basically stock 04 MN6 Vert.

After the install he stated he had a very good seat of the pants improvement in WOT performance but,,,he had a noticeable flat spot in the part throttle acceleration (around 2/3 throttle 2500-3500 RPM AND HIS FUEL ECONOMY decreased about 3-4 MPG highway.

So,,,when we met about a month later I gave him the original home ported TB that I had on my 02 ZO6. He IMMEDIATELY noticed better throttle response and the flat spot was GONE!

You NOT going to gain Gobs of HP porting your TB. You will see some throttle response differences and when you add that to ported heads, ported ZO6 intakes, VARARAM, it all adds up and the porting will give even more potential. With the ported TB, you will see more gains with the other mods over just adding a ported TB on stock engine.

I added headers and a VARARAM on my wifes 06 Z51 MN6 Coupe. Again,,,there was a decent WOT gain but, part throttle cruising performance suffered. I home ported the LS2 TB and saw a decent gain in throttle response but it still ran very rich. Cant say if there was a HP increase just from porting but it ran better. After a full performance tune by Chuck at Corvettes of Westchester, WOW!!! There was a SIGNIFICANT gain across the board. Fuel economy is better than stock, there is INSTANT throttle response and it ROCKS under full power!:o_o: The tune put ALL the mods together and allowed the engine to operate properly with the better breathing.

If you do all the changes that you stated,,,your going to need a tune to get the most out of your combination. Do some data logging and see what your LTFTs are before and after the changes/mods. After the mods and before tuning mine were all over the place and it was adding all kinds of fuel. Well over the 25% max


10-18-2009, 09:46am
I got my stock Z06 throttle body polished and ported by Shanner. It was rough as hell inside before, and smooth as glass after. I don't know if I felt a difference in HP, but I did notice a crisper throttle response for sure.


10-19-2009, 02:43pm
If you move enough air it will matter, think FI...

All others, not so much...