My friend just got a Brand new GMC 2500 Sierra 4X4 SLE crew cab,4L80,4.10's, full loaded, w/6.0L. He was wondering what kind of times it would run 1/4 and 1/8(et&trap)and what kind of power it should be putting down?

 

that sucker is HEAVY.. im gunna guess 17 - 18 1/4 times, but i really have no idea

 

Well, I have an 8.1 but I am burdened with an Allison transmission (which robs more power) so in the end, in drag racing situations the 6.0 and 8.1 would turn nearly identical times. Weight is the difference and I imagine a regular 2500 weighs a little less than my HD with heavier axles, suspension, frame, engine, etc. My times are in my signature.

 

i am going to run my 2500hd ecsb soon.

2wd, 4.10's, 6.0, i hope i can run some low 16's. it feels faster than my 99 classic 1500 with a vortec 350 felt and it ran a 15.90.

 

Mid-high 16s at around 85mph.That is a big heavy truck for a 6.0 to haul around.I have a 6.0 3500 Express cargo van that feels quicker than my 2002 HD 8.1.Please post times.I think you will find their is little difference between the 8.1 and 6.0 in a drag race.Hook a 12,000 lb trailer to the hitch and their will be a big difference.

 

The reason your 6.0l feels quicker has a lot to do with the transmission behind it. The Allison just is bigger, more to turn, and as such robs a tad bit more power. The 6.0L just turns a 4L85E.

Another problem with the Allison and I guess I should clarify that it really isn't a "problem" perse, but it shows in a drag race application is the shift pattern of the transmission. It is programmed for towing and hauling, not racing. As such, I find mine shifts from 500-700rpm sooner than I'd like it to and of particular experience, runs through 1st too quickly. If in 2nd, 3rd, and 4th if it'd hold that extra 500-700rpm, it would perform a heck of a lot better. I wouldn't be surprised if it'd knock off another .2-.3 off my listed 1/4 mile time. Unfortunately all the programmers out with parameters for 8.1's DO NOT have the ability to work with and change the Allison programming. Allison has not let anyone crack it's coding. I'm sure someone with LS1edit and the 8.1 module could probably crack it, but even when attempting to mess with mine with a Tech2 didn't get me very far.

Now once a trailer is hooked up to that 8.1 (or D-Max) with an Allison, it's a whole different story. That Allison is a Godsend and shows it's stars and stripes. The tow/haul mode really makes a difference with it and of course the grade braking system is GREAT!! I love slowing down and not having to use the brakes until absolutely necessary letting the transmission do all the braking up till that point.

But that's because it was designed for towing, not drag racing

 

I agree Cmnt.The ally is a work tranny not a dragracer.I tow on a regular basis and have for 10 yrs.The Allison 1000 is the best work tranny I have ever used,bar none(manual or auto).When I drag race my Hot Juiced 03 Dmax the juice cuts the power on the shifts.If it would hold full boost thru the shifts I know I could run .5 seconds quicker.Oh well it probably helps the tranny live a longer life.

 

My '01 2500 HD 4x4 x-cab with the 6.0/ 4L85E, 4.10's, bone stock with 285/75/16's, turned 16.4's at 85 mph. With the addition of a Volant air intake, home ported throttle body, ASP underdrive pulley, and Superchips tuning, it turned a 15.73 at 89 mph. I've since added Arizona Speed and Marine headers, and a magnaflow muffler, but haven't ran it at the track with them. It definitely pulls harder though. AS & M claims 25 rwhp on the 5.3's, so I would guess the same for the 6.0. People say "oh, it's just the 6.0", but I've raced two chipped duramaxes, and beat 'em both. I pulled against an 8.1 and a duramax at a truck pull, and beat both of them also. I love that motor.

 

Good times for a 6.0.You should have no problem beating a 8.1,they are biased for towing.The Dmaxs you raced must have had a mild programmer for you to beat them in a race.They would have handled you quite easily with a aggressive programmer.My Dmax went 14.88@90.31 spinning half way down the track.I'm going to the track this week and should better my times.It seems odd that you would be able to outrun a truck(Dmax) with twice as much torque as you have.The programmer I have adds 325rwtq.Even the mild ones would be in the 650-700 flywheel tq range.My 6.0 3500 cargo isn't even close to my Dmax in acceleration.You must have out drove them.

 

Not necessarily.

His 6.0L had
-Volant intake
-Ported TB
-ASP underdrive pulley
-Superchips tuning

This netted him 15.73 @ 89mph

He has since added a set of AS&M headers and a Magnaflow muffler.

My stock 8.1 with a boat anchor Allison ran 15.84 @ 86.54 mph. If I had the same mod list he did, simple cubic inches and torque will win the battle every time especially when considering the mass that is needed to be moved. You'll see his stock time was 16.4 @ 85mph. So you can see what I'm getting at.

Not discounting his times, that's damn good considering the weight and engine combo, but you need to compare apples to apples and oranges to oranges. A BBC uncorked will scream!