'08 GMC Sierra 4.10, 6.2L, 6L80E does 13.1!

[SSilveronyxx]

iamkeniff is my new hero!! He dyno'd around 380 rwhp in 2nd with the 4L70. (DYNO VIDEO THREAD) My Guess is that my 600+lb LIGHTER AWD TBSS should easily be in high 12's!

http://www.performancetrucks.net/for...d.php?t=477778

http://www.youtube.com/watch?v=TCRU9..._order&list=UL

http://www.youtube.com/watch?v=7Pu6Y...=20&playnext=1

http://www.youtube.com/watch?v=BhI-g..._order&list=UL

The highlights:

'08 GMC Sierra Quad Cab 5.3L, 4L70E w/4.10 converted to cammed("228/236 .588.601 112+2 or something like that"), LT, 6.2L, 6L80. Easily a 5200+lb truck



"22mpg vs 18.5"

"60' 1.968
330 5.594
1/8 8.512
MPH 84.68
1000 11.017
1/4 13.135
MPH 106.42
not bad for a STOCK STALL 6L80e with small LTs.
its hitting the rev limiter on the 1-2 and the 2-3"

"yeah it spun on DRs looks like i need to drop it off to Madman again. i cant complain for a cam that has no low end..."

[SSilveronyxx]

Just a peek at what 5000+lb, 3.73 gear, 6L80 trucks are dyno'ing and running:
http://www.performancetrucks.net/for...d.php?t=471612


Signature:"2010 ecsb 6.2 2wd | 364/383 | 13.32@103.01. Kooks 1 7/8's LT's | catted 3in y | magnaflow muffler | k&n drop in filter | my personal tune"


and might as well see what the 5000+lb 3.42, 6L80 trucks are dyno'ing and running:
http://www.performancetrucks.net/for...highlight=dyno

Signature: "2010 GMC Sierra Ext Cab SLT 2wd 6.2L/6L80 w/3.42's 13.64@102.51mph 2.21 60' on 17'sm HP Tuners, CAI, Longtubes, Catback, UD Pulley, DynoJet 367rwHp/390rwTq on 22's"

[OutBurst]

There you go - what you and I have known all along!

[lt1z]

6 speed auto is helping alot. A 4.02:1 first with 3.73 final drive launches and the extra gears mean less rpm drop throughout the run. If only the TBSS came with a 6l80 3.73 combo from the factory.

[NORCAL SS]

did you say 2nd gear dyno?

[lt1z]

There is no 1:1 gear on a six speed. 4th would be closest at 1.15:1

[z28tranz]

Damn good for the weight and stock stall!

[svensk]

Weird he only ran a 13.1 with that 106mph?? I'm thinking the pig still needs help getting off the line?

/edit he should be cracking into 12's no problem with that mph.

[06WhiteSS]

What did he end up spending overall? I am tempted to do this setup in my Tahoe, but everyone says its horrifically expensive.

[SSilveronyxx]

He updated me:

"yeah buddy, its the 6.2/6L80e 4:10s on 28" M&H DRs
it hit the rev limiter on the 1-2 and the 2-3 on all 3 runs.

its got milled heads .020" stock ports, stock intake, 90mm TB, 4" CAI, UD crank pulley, 228/236 112+2 cam, 36" muffler, 1 3/4" LTs and 3" exhaust, Truckshop tune. all runs were made with 1/2 tank of gas"

Doing a Tahoe should cost you under $5k...less if its RWD.

[iamkeniff]

hey guys, i dont get over here too much.


the 6L80e cost me 1000 w 19k miles. came with the converter, cooler lines. im actually running a 2010 Camaro
SS 6L80e. it requires a modified bolt in TH400 yoke. machined ID to fit the nut and machined shorter so it has less sticking out of the tailhousing.

i have 1k in the trans, 200 roughly in the harness, 500 in a custom driveshaft with Spicer 1350 u-joints, 300 in a custom Carrier bearing mount so i can run a 2 peice driveshaft. so roughly 2k, not invluding 100 for dexron VI trans fluid, 85 at the dealer for trans filter, u-joint straps, bolts. all i did for my transmission mount was turn it around and drill a hole. the car trans pan has a shallow point for the exhaust to run. im running 99-07 classic Pacesetter LTs, an modified Y pipe so it'll clear the pan.

mods are listed above, and that is a Brandon (262 i think is his s/n) custom cam.

i had the PI3600/4L60e and the truck had a best of 12.73 @ 104.54 with a bad trans and backed itself back up with a 12.74 @ 104.95 73* roughly.

it drives a million times better with this 6spd vs that 3600 converter. im sure it would have been a 12.9x pass i it wouldnt have hit the rev limiter twice. all in all im VERY happy with the stock stall 6L80e



keep in mind, im not mechanic guru, just a do it yourself kinda guy. i did everything but the tune, driveshaft.

[SSilveronyxx]

Are you hooking off the line? What's your launch technique?

[iamkeniff]

dead hook no issues there. the stock stall only goes up to about 1800-2000 im not really sure. my cam needs a 3400+ converter to 60' in a big ass truck. the truck use to cut 1.76 60' on a 3600 converter and went 12.73 and 12.74. i bet if it wouldnt have hit the rev limiter twice it would have been a 12.9x pass. id take a .2 lose in E.T and a 2-3mph gain to have a truck thats a ton easier to drive.

[lt1z]

6l80 ratios with a 4.10 gear and 28" tire will do the job on the strip. A Yank 3200 would be killer.

[iamkeniff]

ill stick with a stock converter thanks to the price of buying a converter lol.


its getting put on the dyno thursday for a VE retune, and the trans to be tuned more agressive at WOT but 1/4-1/2 throttle i want it to drive like stock.

[SSilveronyxx]

An interesting and informative debate we had over on LS1Tech.com complete with charts and graphs!!

6L80/90 vs. TCI 6X vs. 4L80 vs. 4L70

[Karch]

Originally Posted by SSilveronyxx

An interesting and informative debate we had over on LS1Tech.com complete with charts and graphs!!

6L80/90 vs. TCI 6X vs. 4L80 vs. 4L70

Oh no...I'm not subscribing to that mess I just read most of it....fahgetaboutit.

Seriously, to me, the whole point about an A6 is being lost over there. It's not about what's faster down the 1320, but what is a better DD trans, cost notwithstanding. Again, this is my opinion.

If I were racing an 800 hp/tq powered vehicle, I would choose either a TH400/4l80 or perhaps, if the car was under 2400#, a powerglide, believe it or not.

Plus, it depends where that power comes in at.

My 455 is a f'ing animal right off idle. My buddy has one similar, and the dyno couldn't hold it back below 3K rpm, and that's in 4th gear (manual trans). The smallish ports and long stroke (4.21") builds torque early and fast, and then it's done early as well.

He made something like 440 at the wheels on a Mustang dyno, with a restrictive intake (I told him), and his torque worked out to around 456, and he was like 450 ft-lbs from 3K to 4600...flat!

Also, you cam your engine for the combo....less gears, usually a wider LSA, as you need to broaden the torque curve. Heavier vehicle, wider LSA, same reason.

Lightweight, lots of power, TH400....go with a narrow LSA, the weight allows you to overcome inertia and start accelerating.

OK, I'm done...taking my son skiing in the morning for his first time.

[iamkeniff]

the cam i have was designed around the 60e an a 3400 converter. it ran slower on 3:42s and a 3200 but it was an insane roll racer. the cam wont be coming out anytime soon since i like my 106mph and im buying a house so im happy with what it ran. its getting a new dyno tune tomorrow and some more timing since im only running like 21-22* i think

[SSilveronyxx]

Does your tuner know how to play with the traction control settings? I'm playing with mine, b/c it sucks having a peg leg rear end. I'll just have to re do it with a posi rear.

[iamkeniff]

i have a tru-trac an i had a hell of a time with the traction before the swap. all i know he did something and my truck will light 'em up as far as i want, an will not shut my truck
down.