Pontiac G8 Forum banner

Throttle body porting!

11K views 39 replies 10 participants last post by  DavidMay 
#1 ·
anyone tried chances with porting TB?

I've read over in Camaro's forums it's building good buzz, and reporting fair gains with the maros V6 of 10+rwhp!
 
#5 ·
Intreasted...........
 
#10 ·
Contact, Rick Crawford.....from what I have heard a bunch of guys have had their ported by him on a GT. I waiting on him to let me know when he has one back in stock to get one.

Sent from my Inspire using Autoguide.com
 
#11 · (Edited)
Vmax confirmed 'll do porting for our V6 TB, like done for camaros.

Quoting Vmax:
" As far as we know the G8 has to run the part nr you sent me, the side mounted plug, because your computer will not read the throttle position information sent by an LLT throttle body. I have hand ported this type of TB. The LLT and G8 bodies are basically the same and the G8 responds to the same modification as the LLT 2010-2011 and LFX 2012".
 
#13 ·
$150 for the porting job+shipping (their price as with camaros). Basicly they'd need your TB to work with.
With camaro crowds since its more going item for Vmax, they would send you ported unit with core charge thats refunded to you when you send them your old TB. But for G8 I dont know how they'd sort it out in US.

Unfortuantly for my case, it'd be outright sale :(, including new OE body, coz international return shipping will be not visible.
 
#15 ·
As far as I could find, although LY7 & LLT V6s have similar throttle bodies, but seem they have different plugs!, and sure different OE part numbers of throttle bodies
G8 V6's TB: GM # 12615503 (new # replacing older ones)
Camaro V6 LLT's TB: GM # 12616194 (or figures in other order)
 
#22 ·
Unless I'm looking at the wrong part, a new V6 TB is only 75ish US. Buy it, have it shipped it to Vmax for porting, then shipped to you.
 
#23 · (Edited)
Since in OEM throttle body porting, the TB flab blade size won't change (hence what can be considered as a bottle neck for air flow), I tired to search where possible gain may come from. Following is what I could come out with.

This is an exagerated sketch of porting on OE throttle body, keeping OE flab plate.


From above:
(A) Partial Throttle, porting OE TB relates as giving more gap space to air flow at a given partial throttle position %P. The increased air flow (due to increased gap) translates to increased power at that given partial throttle %P. If we draw power vs TBP grapgh, we would notice power band shift toward lower TBP values. In real life, reporting "better throttle response" IMO is just descriping this shift of power band curve (more power for less throttle).

(B) WOT, the bottle neck remains same (OE flab size not increased), hence wouldn't see direct increase in air flow that can actually add direct power gain. But due to shape of air flow passage, Ported TB shape might have "less friction" to air flow compared to original OE TB. This might yield few horses to power peak.


:dunno:!!
 
#25 ·
I guess "porting" should go little farther than "polishing" by removing littl material from TB inner wall surface. Although both work in same line, to reduce friction to intake air flow (by more area and/or less wall friction).

On a side note, got call from postoffice today, I've got package (from Vmax ;) ). Shall collect package tomorrow, but would take few days for weather to clearup and put it on to see what/how it does.
 
#26 ·
At last weather cleared a bit and I got chance to put Vmax ported TB on car today.

Install was straight forward, but took me sometime cleaning trace of my old TB paper gasket .
While at it, I took chance to do little chamfer on intake manifold port entry edge . Also I smoothed/polished intake manifold neck (wherever I could reach inside with my fingers and sandpaper-400). Then cleaned every thing, put new oem metal gasket and new TB. Pluged, reconnected battery, and switched on and let it set idling for couple minutes.

I didnt drive it yet, but from today:
1- got no CEL (myself was worried, because oem TB part number given to Vmax to pick and process, I had %0.001 doubt about, because my car isn't actually 2008 G8 LY7, but the Aussi 2007 variant LE0 engine which is basicly same but not %100 identical).

2- while idling I pushed pedal few times, that intake whistle which I have due my CAI at certain gas pedal position, for sure today came at earlier pedal position.

Thats about it for now. Later will give driving feedback and/or any fuel consumption effect.
 
#27 · (Edited)
Today I drive it with new TB, and got first feel.

- Fuel: Reset dash trip meters. Then on approx 30miles combined city/highway road to work, trip computer showed 10.6Ltr/100km. Previous measure was 10.9Ltr/100km on same road, same traffic hour and conditions (winter and same avg climate). Shall see later if it continues like that on long term fuel consumption average.
Edit: Day3 after ECU reset, have driven around 150miles, did another reset to trip computer, displayed fuel consumption on same road/conditions 10.3Ltr/100km.
(average speed in all measures was 54-55km/hr)

- Throttle response on rolling: This is where I loved it and noticed improvement. Pushing pedal in gradually, response felt more steady and linearly linked to pedal as in "push-go". Previously there was a spot right before autoshift kicks in when car felt like "push-think-wait-go" !

- From a stop: tad little better throttle response. But I wouldn't place high bets on this!

- Power/Torque gains: sorry, no dyno to prove any. And my buttutronic dyno isn't quite accurate below 20hp :)
 
#28 ·
so just to sum everything up here, you sent in your OEM TB to vmax, and they ported it and sent it back to you correct? or did i miss something, and also how much in all did you spend on this mod? and also how long did it take to get your TB back to you after you sent it?
 
#29 ·
having international shipping involved, I didn't do it on exchange base. 2way international shipping wouldn't be feasible!. I paid for core new TB.

I gave Vmax oem TB part number, they bought brand new oem, processed, and shipped to me. It took them around 10days (to get oem piece, and do the porting job), add another 10days till I got it (international shipping).

Vmax charge on porting job -on exchange base: $150.
(and in my case another $210 for core unit and international postage.)

hope I've answered it clear.
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top