2008 G8 GT tunes out there?

[DSteck]

The repository only has a stock calibration, unfortunately. Is there anybody out there with a tweaked calibration for a mostly stock G8 GT? A local guy is wanting some tuning done on his G8, so I wanted to see what people have changed in the tune. He said he's going to do an intake and full exhaust eventually, but I'll deal with that when it happens. I tuned my own car (big cam LS7), but the fact that drastic changes were needed made it easier to tell what had to happen... I've never had to really play with a stock car. WOT is the easy part. Basically, I'm just looking for the limitations for this guy because he wants to switch over and run 93 octane all the time, but I don't know anything about the L76 as far as what it likes for timing.

On another note... I've never had to mess with an auto car before. Is there a way to force the transmission into a gear and lock the torque converter through the scanner? This would be for dyno pulls. I don't have my laptop or interface right now, so I can't load it up and check to play with it.

[EC_Tune]

Generally if the transmission is in Tap Up Tap Down mode it will lock the converter as well. If not you just need to adjust the TUTD mode so that it holds the gear and doesn't shift automatically.

As far as tuning goes it should be pretty easy. Just MAF & Timing in general.
If you're on a dyno you can check knock sensitivity as well. If it knocks and you pull timing and it still knocks, its the sensitivity. If you add timing and torque goes up you know its not knocking as knock will kill torque. With the E38/E67 series ECM's you can adjust the sensitivity by cylinder. Just increase the values until the KR goes away.

[1BadL76]

We just picked up our 08 G8 GT on Thursday, took it for some basline testing at the track on Friday, removed just the TM, and raised the rev limit to 6500 and shift point to 6300 and gained .5 and 4 MPH. I will put in a WBO2 bung in Monday and put it on the dyno to work with MAF tuning, PE fuel, and adjust the timing. I'll post the numbers when I get it done. Our dyno is a new SuperFlow Autodyn 30, so I'm sure it read these cars low.

[G8Paul]

Wow nice gains from just raising the rev limiter a tad. WHats the safe limit for redline?

[1BadL76]

I wouldn't put it higher than 6500. We shift it at 6300 at the track and seems to be done making power by then. The biggest gain, so far, is from removing the torque management on these cars, which is pretty limiting.

[1BadL76]

Got it on the dyno late last week. Thought some one might be interested in the numbers.
Bone Stock:277.6 hp @5,268 rpm and 308.7 tq @ 4,216 RPM
Lingenfelter CAI: 287.5 hp @ 5,205 RPM 312.2 Tq @ 4,293 RPM
Air/Fuel was a rich 11.4 above 5,000, timing was at 24, cooler morning runs were made at about 66 F on 91 octane.
This was on my new SuperFlow Autodyn 30. I figured the numbers to be pretty good on this dyno.
I worked on the air/fuel in the PE table and got it to 305.7 hp @ 5,342 RPM and 322.6 TQ @ 4,344 RPM. I am still working on the timing tables and have little more room on the AFRs.

[Doc.SS]

nice numbers for a days work...

[rushhour]

Well done -when you get it all done - you have to point us in the right direction - my wifes car is screaming for a tune (and a bit of track time - hope she is not looking at this).

Steve

[1BadL76]

LOL, will do. We have some headers and a MagnaFlow exhaust on the way so we can get tunes worked out for these mods as well.

[Pro Street]

LOL, will do. We have some headers and a MagnaFlow exhaust on the way so we can get tunes worked out for these mods as well.

What kind of #'s did you get with the headers?

[Bad Habit Z]

I'm curious to see what seems to work best as well

[johnh]

Subscribed

[EC_Tune]

Any G8 GT's want some dyno time in the LA area give us a call!

[Zim]

lol damn it! When can't you come to jersey!! lol

[boomer]

Any G8 GT's want some dyno time in the LA area give us a call!

where in LA are you?

[EC_Tune]

where in LA are you?

7444 Reseda Blvd. Suite K
Reseda, CA 91335

[Zim]

So...?? Any more progress?? Interested in a tune file if possible?

[Pro Street]

I went to the track last Saturday with my 09 G8 GT.
run 1
13.68 at 103.68 2.182 60'
run 2
13.70 at 103.43 2.189 60'
run 3
13.67 at 103.38 2.131 60'
Car is all stock with some trans tunning and a few tweaks to the pcm!

[Zim]

Funny, that's what i got and it's stock too! I need to find my time slips....

[Pro Street]

Funny, that's what i got and it's stock too! I need to find my time slips....

I was at Thunder Valley at Noble,OK. for the Buick vs Ford race when I ran these numbers.