Info: Allison trans in 2.6 truck

[ikeG]

Do you agree you cant get the same amount of rpms off the line with an allison as you can with a standard. Or are you saying its a wash, Interested to hear your opinion sir.

Obviously you cannot get 4500+ rpms out of an allison before launching. But will an allison truck properly setup, you can leave with enough boost to leave just as hard. I'm also not convinced yet that blowing the tires off immediately before moving 2 total feet is better than what we are doing with an auto....

 

[Yellow Jacket]

3.42's ain't enough for around here. Not sure bout MN. If you're actually making four digits, need to spin em harder than 3.42 will.
A 3.42 ring and pinion are physically the strongest set you can put in an AAM. The size but more importantly the gear mesh. They will hold so well that while others are swapping r & p every few hooks, you are still going strong. The problem with this is it moves the driveline strain further along to the next weak point. Normally the pinion shears in half and the ring gear sends it down through the case, which is not repairable. Junks the entire housing, along with r & p. At his point, I would rather inspect and/or replace ring/pinion every little bit instead. Plus, like i said, 3.42s arent fast enough unless you're sticking to brush pulls. Welcome to 2.6! SMH repeatedly

I watched MULTIPLE 1200++ horsepower 2.6 trucks fall off chargers with 4.56 gears, 35's, and 1:1 in the trans last year local to me. We have pretty good tracks around here...

 

[ikeG]

I will be running a Precision 2.6X3.6 turbo, do you think 3000rpm is high enough stall to light it?

In 3rd gear low range, a 3000 stall converter should stall at a bit more than 3000 actually. So yes, probably. Definetaly high enough for a 4th gear start, maybe too high. I know the latest precision's appear to have only 2 housing a/r options and they both dont seem crazily loose. Matt Sparkman runs a haisley hx60 and lights it just fine. A guy on here ran a allison last year and was able to light a S500 variant with it just fine.

 

[Muff]

Obviously you cannot get 4500+ rpms out of an allison before launching. But will an allison truck properly setup, you can leave with enough boost to leave just as hard. I'm also not convinced yet that blowing the tires off immediately before moving 2 total feet is better than what we are doing with an auto....

Im convinced. Once the truck does hook your rpms are still higher than the auto guys and will carry more rpm/wheel speed down the track. On shit tracks its 50/50 auto vs standard in my head, but on good hooking tracks standards have an advantage. IMO

 

[ikeG]

I watched MULTIPLE 1200++ horsepower 2.6 trucks fall off chargers with 4.56 gears, 35's, and 1:1 in the trans last year local to me. We have pretty good tracks around here...

One the best 2.6 duramaxs in the nation is rumored to be running 4.10s & 35s in a zf6 running direct and not snuffing. Finishes well at national events too.

 

[Yellow Jacket]

Do you agree you cant get the same amount of rpms off the line with an allison as you can with a standard. Or are you saying its a wash, Interested to hear your opinion sir.

When we were probably 1200-1300 HP with a 3.0, we left the line around 4200-4500 and when I would look at logs we would pull down to 3500-3800 depending on bite upon slipping out the clutch... Leaving with an Allison at 3000 and some boost it will jump up that 500-800 rpm upon releasing brakes and letting 'er eat... Same effect, a manual has to leave at high rpms to get boost up because of lack of load, the auto does that for you.

Obviously you cannot get 4500+ rpms out of an allison before launching. But will an allison truck properly setup, you can leave with enough boost to leave just as hard. I'm also not convinced yet that blowing the tires off immediately before moving 2 total feet is better than what we are doing with an auto....

Bingo, not saying an auto is the answer, but leaving as soft as possible can be your friend...

 

[duramaxzak]

Looks like Matt Sparkman is running a 3500rpm stall from his for sale ad.

 

[duramaxzak]

Thanks guys for sharing, seems hard to get info from alot of the pulling guys.:thumb:

 

[Yellow Jacket]

One the best 2.6 duramaxs in the nation is rumored to be running 4.10s & 35s in a zf6 running direct and not snuffing. Finishes well at national events too.

Just that, rumored... And if that's the case, the chassis doesn't bite well, but not every truck works with bite, sometimes wheel speed is your friend.

I'm not gonna lie, I almost couldn't believe the final drive we pulled once getting our truck up and running this year, but it upset our chassis badly and had some changes that were made to help correct the problem.

 

[ikeG]

Same effect, a manual has to leave at high rpms to get boost up because of lack of load, the auto does that for you.

Good point I overlooked. I'm not saying an auto is the answer either, and i would much rather have a zf6 personally. But not because i think it would do that much better.

 

[x MadMAX DIESEL]

I tried some high stall tc 4th launch, both goerend and precision. Both make it 1-2 passes before burning up. Maybe I had something else wrong idk but I swapped over after that

 

[ikeG]

I'm not gonna lie, I almost couldn't believe the final drive we pulled once getting our truck up and running this year, but it upset our chassis badly and had some changes that were made to help correct the problem.

And i think the learning curve is straight up for us...... 3.0 right now is just absolute insane. Making enough power to make 6 35 inch DOT tires seem useless!

 

[ikeG]

I tried some high stall tc 4th launch, both goerend and precision. Both make it 1-2 passes before burning up. Maybe I had something else wrong idk but I swapped over after that

Hard to beat the repeatability and reliability of a suncoast in this application.

 

[x MadMAX DIESEL]

Hard to beat the repeatability and reliability of a suncoast in this application.

Well maybe I should say that was with 3.73 gears, lots of stress. Either way found a zf6 for 500 bucks couldn't pass it up

 

[Muff]

When we were probably 1200-1300 HP with a 3.0, we left the line around 4200-4500 and when I would look at logs we would pull down to 3500-3800 depending on bite upon slipping out the clutch... Leaving with an Allison at 3000 and some boost it will jump up that 500-800 rpm upon releasing brakes and letting 'er eat... Same effect, a manual has to leave at high rpms to get boost up because of lack of load, the auto does that for you.

Sooooo. Standard ends up at 35-3800, allison ends up 3300 at the end of the track? If we're agreeing that the standard ends up 500rpm above the allison ill take that wheel speed every hook.


Bingo, not saying an auto is the answer, but leaving as soft as possible can be your friend...

Disagree, leaving soft is only your friend on shit tracks. With good tracks and speed sleds drive the truck off the line and be ready for the weight to hit.

 

[onebaddmaxxx]

Past 2 years have ran 3rd gear only with stock gears (truck is a 2.6 puller with a s475/96 turbine t4 foot and ran a sun coast 1055 converter. Can spool the turbo within 5 seconds of building it up at the line. Full spool almost instantly never have to ride it out to spool. That was on a 33" tire

Next year going 4.56s and gonna run 4th only.

 

[Yellow Jacket]

Disagree, leaving soft is only your friend on shit tracks. With good tracks and speed sleds drive the truck off the line and be ready for the weight to hit.

You are right, and I was too, lol! I was speaking from our experience this season. We used to drop rpm when we would leave hard and get out of clutch, this year if I get out of clutch at 5200 rpm engine goes to 5500 and stays there, lol. If I came out softer it would pull it down, then go full throttle and pick up 500+ rpm. Night and day from when we had 1200-1300 HP. Not sure what we have now but I'd bet 1600-1700.

 

[durtymax]

I ran a Allison in '13 with 35's, 4.56 and 3rd start, shift to 4th. We pulled almost exclusively ppl. I took '14 off due to work. Now there is a zf6 sitting in the shop now. These guys all bring up great points for both. As I always say there is more than one way to skin a cat. Every time I thought I needed to go to to a zf, rob hall would hook up to the sled, start in 3rd, bang 4th and lockup very quickly. And go down to the other end and finish well. So it can be done with success. What works best for one may not the other. Just my 2 cents

 

[duramaxzak]

So it's sounds the like the Allison tranny should hold up fine, it's more the life expectancy of the converter that's the problem?

 

[onebaddmaxxx]

If you get the correct converter that can get on your converter efficiently, and don't get it hot as balls, it will be fine. Like I said 2 seasons in our 1055 with a 75, 100%s and dual pumps doing 3rd gear starts.