Here's the deal, my wish list for a tow rig has been a Chevy 2500 HD with the Duramax/Allison combo. I am getting closer to actually buying a used one and found prices to be around 25-27k. Well, I found a good deal on a GMC 3500 HD with the 8.1/Allison combo for a pretty nice price. It is a 2004, low miles and is loaded out with extras, setup to tow a gooseneck, etc. I searched and came to the conclusion that either choice will pull a load pretty damn well. However this will be my DD and I don't want to be killed at the pump by the 8.1. Anybody had both trucks and can give me some real world fuel economy numbers? Any input or experiences would be very helpful.

Also the 8.1 has an intake and exhaust, and the owner is claming 12-13 around town and 15 on the hwy. Let me know what you think.

He is lying or has an incredibly light foot. My buddy and I both have '05 2500's mine is diesel his is gas. I get another 100 miles out of a tank and can pull him up hills at half throttle. Get a diesel unless you want 8-10 mpg

I had a friend with an 02 that got 4-5 mpg on 36" tires. Im not sure about stock. It had tons of power but even after a custom tune, intake, exhaust and gears it drank gas.

Daily driving my wife gets an overall average of 11-12 in her 8.1 Suburban with 4.10 gears. I get an overall average of 13-14 in my CC 4x4 Duramax with a heavy foot.

I like my diesel, but that 8.1 pulls real good.

Blake

I get 14 mpg all the time with my 8.1 Av w/ 4.10s. (empty, 9 mpg towing 10 000lb). A dually will get worse.

I also got worse daily driving a CTD 600 and a 6.0 PSD. However a co-worker has a similar commute and gets 17 with his Dmax, although its an '06 with the extra OD.

Basically if you are doing a ton of highway, I think the Dmax will shine, if you are in stop and go, I doubt the savings makes much difference, esepcially sicne here the price of diesel is 15% higher.

The 8.1 is nice in that it doesn't need to warm up or cool the turbo down, its cheap to maintain etc... I wouldn't hesitate to buy another one, but would really enjoy a diesel for towing long passes at 10 000' loaded at 12+klb.

Thanks for the input, my commute is not bad now but will be about 40 hwy miles round trip once our new house is built. The truck I am looking at is a SRW 1 ton, so it should be pretty close to what you get. If it has 3.73's it might even get better mileage

Try using the Search feature. Lots of info there

I did that and spent a lot of time reading through it. Just wanted to get some more updated info and see if anyone has had both trucks.

I own both (both are '03', crewwcab dually's) and I just had both trucks on a trip from Dallas Tx here to Montana each pulling 14,000 lbs. The Duramax has Banks everything and an Edge programer and the 8.1 is stock. The 8.1 averaged between 7-8 while the Duramax averaged 11-13. Both of my trucks are lifted and each one carries 800 gal (3200 lbs) of fuel in the box. I think I spent about $200 more in fuel for the gas motor (1600 mile trip) but in real world driving I dont think the Duramax is that much more of a money saver. I can say that the 8.1 can keep up with the Duramax anywhere, hills or flats. I also have a 7.4 van and the 8.1 will walk all over it. I have never been able to decide which one I like better (depends on current fuel prices I guess) but I hope this helps.

no offense to anyone but real tow rigs do'nt have spark plugs. my 91.5 ctd gets 26hwy empty 18hwy loaded lotsa hills and no slowing down. Curious as to what anybodys duramax gets for egt's mine climbs to like 1300(loaded w9500lbs).

Thanks for the input, my commute is not bad now but will be about 40 hwy miles round trip once our new house is built. The truck I am looking at is a SRW 1 ton, so it should be pretty close to what you get. If it has 3.73's it might even get better mileage

And it probably weighs slightly less then mine empty (the av is a pig).

Also you get either an Allison or a ZF-6, the Allison will have more loss then the 4l85e but also has a higher OD and locks the T/C in more gears. Plus I would love to have the extra gear of either of these two (on one of my biggest climbs, I need ~ 1.8:1 and my only choice is 2.48 or 1.48).

Personally if I was ordering a new truck I would look long and hard at the 8.1 again.

I own an '02 with the 8.1 and I run on 35's. I pull about 11,000 lbs when I pull my rig (I'm afraid to check mileage when pulling). I get 11-12 empty even on the 35's. With the stock tires I would keep up to any Duramax but I would obviously go through more fuel. I am thinking of going to the diesel myself because of the easy upgrades you can do, and a lot cheaper than the 8.1 upgrades. The one thing that is holding me back is the price of diesel vs gas, around here diesel is about 50 cents more per gallon so it isn't a big savings when you compare the numbers. I don't know if that helped you or not but that's my 2 cents worth.

Yeah I am kinda torn on the subject still. I broked it down on the Duramax averaging 18 mpg and the 8.1 averaging 13 mpg, and the cost per mile (based on $2.00/gas and 2.35/diesel here in AL) came out to 13 cents per mile with the Diesel and 15 cents per mile with the 8.1, so basically a wash. If you drove on average 20,000 miles a year, the diesel would only save you $400 in gas money, not including the extra cost associated with buying a diesel truck (~$5k). I just don't know.

Don't forget about more expensive oil changes too

Ive never actually driven an 8.1 pickup, just an 8.1 Suburban. Definetly had some balls, but I dont want to think of the gas mileage. Also SOME 8.1's drink oil like its beer. With the 8.1 I hear people get 10-12 no matter how they drive it...with the duramax it varies HUGELY. Around town I get about 16, maybe a bit less depending how I drive. Although on the highway, I get about 18-19 depending on hills, how steady I keep my speed etc.. Thats going ~80mph tho. I was hauling ~2000 pounds of engines, transmissions and shit back from pennsylvania one weeknd and kept my speed 60-65 and got 20.9 mpg. Hand calc, if you have a chip the DIC sucks (no pun intended) at calculating mileage. 2000 rpm and slightly under is definetly the sweet spot for best mpg on a duramax. Towing 12,000 pounds at 65mph I get maybe 13 to 11, depending on hills.

I bought a 03 cc 8.1/allison, 3:73 gears and 305's. I drove it for 60k. I got 10 mpg towing under 70 mph throught the mountains, 8 at 75 mph and above, my wife got 6.5 going 85 with the cruise set going west through kansas. All this towing 8k. DD 40 miles per day I got 12 mpg, highway flat empty I got 15 mpg. I switched to 4:10 gears and noticed no difference in mpg only it stayed in overdrive better while towing. I now have a 03 cc Dmax. swapped in the 4:10 gears and 305's. empty same trips as before I get 21mpg. towing I am getting 14mpg, dd I am getting close to 18 mpg. the only mods are the gears, Hypertech set on level 2 and a k&n filter. I did have the filter and Hypertech on the 8.1. By my math I am getting 40% or better fuel economy. I wish I had bought the Dmax the first time.

Hope this helps, This is about the best real world test, same years same tires gears ect.

Rob

I did also swap in 4" turbo back exhaust, I do not know if this helped. It had duals out the back and the spare tire would not fit.

Go with the duramax. it will out pull the 8.1. I drive an 02 cc dually and frive the hills of california sierras and can do about 9-10 pulling big hillls for hours. pulling about 12000-13000 lbs. no mods to anything except a true flow air filter.

What kind of cruzing RPM with the 4.10 on the dmax? 5 or 6 speed allison?

Great info Matzell, especially since you owned both trucks. I finally got the pics of the 2004 8.1, nice truck but didn't like the long bed. I have made up my mind that I will just hold out of the Duramax (since that is what I really want). Thanks for all the info guys!

And I promise you wont regret it! After driving and pulling with 7.4's in my last three duallys, I finally stepped up to the 06 Duramax last year. It's such an awsome truck. No more 8-10mpg! Now I average 14mpg. If I reset the DIC on a long highway drive unloaded I get around 21mpg.

Go with the duramax. it will out pull the 8.1. I drive an 02 cc dually and frive the hills of california sierras and can do about 9-10 pulling big hillls for hours. pulling about 12000-13000 lbs. no mods to anything except a true flow air filter.

What kind of cruzing RPM with the 4.10 on the dmax? 5 or 6 speed allison?


tcc locked up in overdirve at 70 mph I turn about 2100 rpms. Some say this is a little high for fuel economy but I am also running 305's (33's) wich puts it almost back to stock with these gears. Most of the speed limits in VA are 65 max. I normally tow around 75 or with traffic on I-81.
I am loaded and heading to Paragon, Pa this weekend I will see how it does at higher speeds up north. I can only imagine it will hold overdrive better at the higher speeds. I will have a couple of gassers following me up so now my wife will actually see the difference in fuel milage compared to them.

Go with the duramax. it will out pull the 8.1. I drive an 02 cc dually and frive the hills of california sierras and can do about 9-10 pulling big hillls for hours. pulling about 12000-13000 lbs. no mods to anything except a true flow air filter.

What kind of cruzing RPM with the 4.10 on the dmax? 5 or 6 speed allison?

no such thing as 4.10's on a duramax. You can only get 3.73's. Cruising 70mph on a 5speed allison, 33" tires, is right around 2000rpm. 6 speed Allison drops rpm's about 300, so youd be around 1700rpm at 70mph with 33's.

My old Vortec 6.0 got 10 flat on stock 245s, 8 flat lifted on 35s. Flat I mean totally empty highway, or 10k trailer thru the city... .no matter what 8 mpg. I hear 4-6 loaded-unloaded from peopel in the 8.1 My LLY Dmax gets about 14 with an extremely heavy foot, edge on 3+, intake exhaust boost stick and a couple other goodies. The 6.0 had intake exhaust tune. My EGTs on my dmax get to about 1350 towing big loads sometime, thats with a catless exhaust system as well.

I hear 4-6 loaded-unloaded from peopel in the 8.1 .

Those people are liars (or are towing 15+k) The absolute worse I have ever got was towing the Dodge (~18k GCW) into a 50 mph head wind up some significant passes in southern Colorado. I still got 7 mpg and was tached out running 65 mph @ 4500 rpm. Left the daily drivers (V6 Toys) and stock diesels ('02 CTD, and 7.3 towing smaller trailers) in the dust. Only the chipped guys kept up.

496 cubes make up for a lot. I never got better mileage with my 6 liter work truck, hell my 5.9 Dodge got worse mileage stock then my 8.1 did.

no such thing as 4.10's on a duramax. You can only get 3.73's. Cruising 70mph on a 5speed allison, 33" tires, is right around 2000rpm. 6 speed Allison drops rpm's about 300, so youd be around 1700rpm at 70mph with 33's.

Matzal said he swapped in a set of 4.10s

no such thing as 4.10's on a duramax. You can only get 3.73's. Cruising 70mph on a 5speed allison, 33" tires, is right around 2000rpm. 6 speed Allison drops rpm's about 300, so youd be around 1700rpm at 70mph with 33's.

You are correct and wrong at the same time. I work at a GMC dealer, I am a service writer. I swapped complete axles out of a 8.1/allison truck to the Duramax. They both have the 9.25 front and the 11.5 rear. This is the only direct swap. I also swapped out the factory locking diff to the AA limited slip uint, much smoother. The other way is to buy gears from somewhere like Randys and install them into the truck.
I know one can not get those gears from the factory in that truck but being here on PIRATE I figured someone would think about changing them.
I am not trying to be smart just thinking outside the box. Where there is a will there is a way. We change the gears in out trail rigs why not our tow rigs as well.


Rob

GO DURAMAX!:smokin: you will regret getting an 8.1, no doubt they are great engines, but the duramax is SO much better! pony up and spend the extra 3K. on average i am getting 13-15 mpg while towing, and 21 mpg highway (around 80mph) with custom EFIlive tuning.

You are correct and wrong at the same time. I work at a GMC dealer, I am a service writer. I swapped complete axles out of a 8.1/allison truck to the Duramax. They both have the 9.25 front and the 11.5 rear. This is the only direct swap. I also swapped out the factory locking diff to the AA limited slip uint, much smoother. The other way is to buy gears from somewhere like Randys and install them into the truck.
I know one can not get those gears from the factory in that truck but being here on PIRATE I figured someone would think about changing them.
I am not trying to be smart just thinking outside the box. Where there is a will there is a way. We change the gears in out trail rigs why not our tow rigs as well.


Rob

I realize you can get 4.10's in an 8.1, which has the same AAM 11.5 as the duramax. I meant you cant get them from the factory like that.:)

Couple guys have swapped out their busted Gov-Lok's for the dodge "Trac Rite" torsen/limited slip setup and been very happy with it. 98% of the time its as good/works as well as the gov-lock, however I have heard of very rare instances where the gov-lock would lock the diff and the Trac Rite would spin one tire. If I blow up my gov-lock I might go to a trac-rite, im not sure...donuts are what KILL's the gov-locks like no other, so I just never do donuts or standing burnouts (tires are too expensive) and hopefully it will last me a long time...

to be honest tho, I see no need for 4.10's in a duramax unless you have ~35's or bigger tires. With 35's or smaller tires, on the highway your RPM would be significantly out of the best economy range... JMO..

ben

I just towed about 10,000 pounds about 1000 miles over the last week. I know the drive through the mountains wouldn't have been as fun if I had less than 500 horse and 1200 foot pounds of torque. My tranny barely showed any temperature and I had to keep the winter front on for the engine to build any heat. I don't think even a supercharged 496 could have kept up, and if it did I'm sure it would have emptied some parts out at some point. Plus, listening to your turbo sing at 35lbs of boost is pretty neat also. The mileage sucked, I probably got single digits, but what do you expect at 80mph on 7-8% grades.

Duramax all the way.

I just towed about 10,000 pounds about 1000 miles over the last week. I know the drive through the mountains wouldn't have been as fun if I had less than 500 horse and 1200 foot pounds of torque. My tranny barely showed any temperature and I had to keep the winter front on for the engine to build any heat. I don't think even a supercharged 496 could have kept up, and if it did I'm sure it would have emptied some parts out at some point. Plus, listening to your turbo sing at 35lbs of boost is pretty neat also. The mileage sucked, I probably got single digits, but what do you expect at 80mph on 7-8% grades.

Duramax all the way.

I think he was looking for more of a stock comparison. Not many bombed 8.1s around, but they will do way more HP not as much torque. Same tranny so I don't see much point in the temp thing.

Have you towed with that monster at altitude? How do your EGTs do at 10 000'?

Thanks for the input guys. Found a sweet 01 Crew Cab Duramax on Diesel Place and I am going to pick it up next week. I am very happy I decided to go Duramax. It has 124k on it, but from what I have heard that aint shit for a dmax. It is already modded out with a chip, exhaust, intake, new tires and wheels, gauges, etc. Can't wait to finally have a real tow rig and ditch the Tundra!!!

I think he was looking for more of a stock comparison. Not many bombed 8.1s around, but they will do way more HP not as much torque. Same tranny so I don't see much point in the temp thing.

Have you towed with that monster at altitude? How do your EGTs do at 10 000'?

I dynoed it at 590 horse and 1390 torque at the back tires. I'm not sure of many 8.1's that have "way more hp" than that, but if I ran into one I'd be happy to hit the blue bottles. My point with the tranny was that I'm runnin at 2100 (give or take 100) in 5th gear lockup pulling any grade in western canada, so the torque converter never gets a chance to spin, to build any heat like when you're pulling big hills at 4500 with your big block. Surely you're torque converter's not locked up at that RPM, which builds heat.

I've never been to 10,000 feet towing i don't think. Maybe? I'm not sure if there's any points in alberta or BC that are that high, but I can say that I've pulled 12,000 pound triple axle trailers from kelowna to Fort McMurray and only slowed down when I get stuck in traffic. EGT's never really creap past 1200, and seem to maintain themselves at 850-900, unless I try and smash the throttle through the floor. Then I can bury the pyro well past 1600.

Stock to stock though, I'd imagine that a duramax would have to pull better than the 8.1, based on power levels alone. My point is that with a few mods thrown at the d-max it'll really wake up and pull better than just about anything else out there.

MR4WD: What the hell are you running and keeping low EGT's,?? Water/Meth, EFI and a different turbo? I'm at 476/1013 and towing 15,000 even when stock I'm around 900-1000. I do still have stock exhaust,stock turbo and stock intake. I can run any speed but EGT's start going way north when I'm running 90mph+. I'll have EFI and a 5" exhaust soon {hopefully} so maybe that'll help.

I used to run a hot edge and either a big ppe or the quad 215. Got me some pretty good times. Now, I run a custom westers tune. Haven't taken it to the track yet, but it runs a fuckload cooler down the highway when towing and the SOP says it's faster. That big Van Aaken is a HOT and OLD box. Duramax performance has come a long way (ie switchable tts) but if you want EFI live and think you can mess with your truck and keep cylinder pressures down to a RELIABLE point, get it.

As far as turbo, I run stock but with a bleeder that lets the turbo spool up faster, build more boost and keeps the EGT's down. I'll probably get that McRat turbo by spring if it holds together over the winter in other trucks.

Other than that, an exhaust and intake will lower your EGT's by about 300 degrees. Aftermarket duramax intakes usually don't flow more air, but they flow cooler air helping in mileage and exhaust temperatures. The difference in a 4-5" exhaust is negligeable. 5" usually has more "brap" to it, a sound distinctive to duramaxes making em sound like a ghetto big block.

I'm at 476/1013 and towing 15,000 even when stock I'm around 900-1000. I do still have stock exhaust,stock turbo and stock intake.


with numbers like that and stock exhaust, egt's will be higher for sure.

I should have guessed Westers since you're up north. I know my VA is old but it is fun.Goes through fuel like a BBC though :mad3: So many people think the TTS is the greatest and it does pull good but IMHO it will be a thing of the past within a few yrs. EFI has unlimited possibilities.

Curious as to what anybodys duramax gets for egt's mine climbs to like 1300(loaded w9500lbs).



18k trailer up a 6% grade, 70 mph, = egt's @ 1250* with 285's.:smokin:

edit: @ 5000' altitude



I own an '02 with the 8.1 and I run on 35's. With the stock tires I would keep up to any Duramax but I would obviously go through more fuel. I am thinking of going to the diesel myself because of the easy upgrades you can do, and a lot cheaper than the 8.1 upgrades.



i call bullshit! there's no way your 8.1, even with stock tires, would be able to keep up with "any duramax". even a dmax with basic $hit like 4" exhaust and an edge/attitude would walk all over you. and that's mild upgrades.

i've pulled against my buddies 2500/8.1 avalanche, both of us with approx 6000 lbs behind and i effortlessly walked up hills, on #2 tow setting, compared to him piss wining his 8.1 to try and keep up. i've talked to folks with stock rigs with the 8.1 and several have said the same thing, "THIS THING'S A DOG".



Found a sweet 01 Crew Cab Duramax on Diesel Place and I am going to pick it up next week. I am very happy I decided to go Duramax.



glad to here your going for the dmax, you won't be dissappointed. best truck on the road, period:flipoff2: . be aware of the injector problems the lb7 motors have though. '01-'04. they will warranty those.

. Maybe? I'm not sure if there's any points in alberta or BC that are that high, but I can say that I've pulled 12,000 pound triple axle trailers from kelowna to Fort McMurray and only slowed down when I get stuck in traffic. .

Thats a lame comparison dude. I used to pull an 18 000 lb goose behind a 454 truck and never dropped below the speed limit all around Calgary.

Come down here and pull some real passes at 75 mph and see what those EGts. No comparison. Hell my POS Dodge could smoke the tires in Calgary and barely could move at the top of these passes.

EDIT
As far as a the 8.1s power, I was thinking fly wheel, not RWHP, the Allison saps a lot probably not many pickups running 600 HP on 8.1s

EFI is good, if you know what you're doing. Build 550 horse with efi, and see how your motor does in a year. You have no idea what you're doing when it comes to cylinder pressures. Big hp/tq numbers won't bend rods as fast as high cylinder pressures from a guy trying to squeeze a bit more out of his diesel in an effort to gain bragging rights in one form or another. Van Aaken is still a good program, but I've run it up to 2000 degrees or so in the 1/4 alone. It's old and hot. For out of the box TTS is real good.

As far as westers, I didn't want it but I smoked my ECM (with my quad) 8 hours away from my house on a long weekend and I was really up shit creek without one, and lyndon helped me out of a bind. For now I'll run with it.

Ramv, I know you're an 8.1 fan and you can probably gather I'm a duramax fan, but do you seriously think you'd whoop me up the side of a mountain pulling a trailer or not? Granted, I've never been to 10,000 feet towing (I don't think so anyways) but I'd be more than happy to adjust the waste gate and turn back the fuel some if I thought my egt's weren't in check. You're talking about your dodge... Is it your wheeling dodge or did you have a cummins? I'd assume your dodge was EFI if it was you're 1500, in which case it wouldn't make it that much different than your 8.1, right? Do you have any seat time in a diesel pulling through the mountains, or a modded one at that? You know about the whole turbo charging thing building boost, right?!

Not trying to create bad feelings here, I just wanna make sure we're on the same page...

Dude you do your best to piss people off since you have been on forums in the last 10 years. No I don't think my stock 8.1 (especially the detuned Av version) would tow with your d max anywhere. Ever. Its 330 hp/440 ft lb torque. rated. It won't tow with a stock '02 8.1, it won't tow with any of the LLY or LBZ, and I don't know anyone with a stock LB7. All I said was the '04 this guy was looking at in the east, with no altittude would do exactly what he wanted for cheaper then a Dmax. Hell, if he posted he was pulling a 15k trailer daily through the mtns, I would have been the first to tell him to get a diesel.

Yes I have plenty of experience with diesels... Work, friends rigs etc. All PSDs , but I can tell you with tuning the altitdue drives EGTs through the roof. The 7.3 stock wouldn't keep up to the 8.1. With tuning it was better but you have to back off big time due to EGts. The 6.0s with some mild programming don't have the juice. They do okay but much like a gasser they run out of steam at altitude if you keep them under 1300. They will out pull my 8.1 but they are spinning at 4k too, and EGTs/Coolant/Trans are higher then mine. Note these are all mild modded ones, no I don't have any expereince with a diesel with more then $2000 of engine mods.

My brother and all the co workers run D maxes in their personal rigs. All seem fine, but consider I work my 8.1 harder then they do, and its just as effecient for city driving, whats the point if you aren't working it?

Your built truck is like comparing a built buggy to a Rubicon. Its pointless, no matter how good an oem vehicle is, you can build something better suited for your purpose.

I dynoed it at 590 horse and 1390 torque at the back tires

wow 590 with a stock turbo on WESTERS. Must be more of that special Canadian air I always hear about. Have you blown your motor yet like every other duramax running westers has? I bet you're running a DTT trans too. :flipoff2: :flipoff2: :flipoff2:

just joking around, no offence meant

i call bullshit! there's no way your 8.1, even with stock tires, would be able to keep up with "any duramax". even a dmax with basic $hit like 4" exhaust and an edge/attitude would walk all over you. and that's mild upgrades.

i've pulled against my buddies 2500/8.1 avalanche, both of us with approx 6000 lbs behind and i effortlessly walked up hills, on #2 tow setting, compared to him piss wining his 8.1 to try and keep up. i've talked to folks with stock rigs with the 8.1 and several have said the same thing, "THIS THING'S A DOG".

.

Ya I guess I left myself open on that one, Let me rephrase that part "any stock duramax"

Ya I guess I left myself open on that one, Let me rephrase that part "any stock duramax"



:)

wow 590 with a stock turbo on WESTERS. Must be more of that special Canadian air I always hear about. Have you blown your motor yet like every other duramax running westers has? I bet you're running a DTT trans too. :flipoff2: :flipoff2: :flipoff2:

just joking around, no offence meant

No, I haven't blown my motor. Have you blown your turbo, smoked your ecm or dropped another allison and busted the bellhousing off during rebuild yet? I'm running an NADP tranny, and at august blackout I had the fastest duramax there, only to be beat out by a cummins. I dynoed 590 on the bastard stack with 2 stages of nitrous, not westers btw.

off the current topic, i enjoy my 8.1/allison in my 02 crew cab 2500hd. definitely enjoy how it plus versus my buddy's 7.3 diesel ford. i just dont do as well on the fuel economy. pulling 16,500 case backhoe + trailer, and i was pretty happy how it did especially once it 'tuned' itself to the weight.

No, I haven't blown my motor. Have you blown your turbo, smoked your ecm or dropped another allison and busted the bellhousing off during rebuild yet? I'm running an NADP tranny, and at august blackout I had the fastest duramax there, only to be beat out by a cummins. I dynoed 590 on the bastard stack with 2 stages of nitrous, not westers btw.

until you tune your truck yourself without smoking an ECM, and until you build your own trans without dropping it, you cant make fun of me for that.:flipoff2: :laughing:

nitrous is silly IMHO, what did the truck make on #2?

until you tune your truck yourself without smoking an ECM, and until you build your own trans without dropping it, you cant make fun of me for that.:flipoff2: :laughing:

nitrous is silly IMHO, what did the truck make on #2?

520 horse. Another westers tuned truck running a less agressive program pulled 540 horse on straight diesel, so I'm confident I'm over that. I didn't have bottle heaters, so the gas was at 600 pounds, but the smoke still cleaned up. I managed to headstud my engine without dropping the heads. You're right, I've never built an allison, but I've built a few 400's and the odd th350.

So, since you tune your truck yourself, what times are you running? Because I designed this westers tune myself and aside of having a laptop next to me while driving, it's about as close to EFI live as I'll get.

So, since you tune your truck yourself, what times are you running? Because I designed this westers tune myself and aside of having a laptop next to me while driving, it's about as close to EFI live as I'll get.

define "designed the tune myself". You work for Lyndon?Whats your max main inj duration at 160 mpA rail pressure? What max main injection timing? Max pilot injection? Pilot injection pulse? What does the throttle base fuel inj quantity table look like?

Saying to Lyndon "this is what I want, can you fix this, can you add a little fuel up top, etc.." is not writing your own tune.

is it balls out on timing so its smokeless like every other westers tune? Are there any Westers trucks running 12's on a stock turbo, no drugs? Why are ~490rwhp TTS Extreme trucks running 12's, and 540rwhp Westers trucks barely doing 13 flat?? Why do you need headstuds with a stock turbo? Again, because westers uses so much damn timing that cylinder pressures go through the roof? :D just kiddin, not knocking Lyndon's work or anything, ive just always been partial to the tunes made in teh states.

as for my track times, what does it matter? Im not paying anyone to make my tunes. I cant launch my truck well for shit, BUt if you must know,7250 pounds, bars lowered, tires aired down, 12.9 @ 108 mph. Look around, generally 108mph is a low 12, so if I could launch it worth a damn it would be faster. Excuses excuses.

but Im not going to argue anymore