Low Power

[05DirtyMax]

I put my truck on the dyno at a local event last weekend and it only made 284hp and 477tq.I have efi live with a 425hp tune from Nick at duramax tuner and everything else in my signature.Ihave 40 inch tires with 22's which i know robs power but i thought in would have made more power than it did.Any ideas why?

 

[Kat]

Something wrong with the dyno maybe? Where there any other trucks done?

 

[05DirtyMax]

Yeah there where other trucks that said there numbers were a little lower than normal but not like mine.It was a mustang dyno.A friend of mine put his 2008 duramax on and it has exhaust and efi live with Nicks 530hp tune and it only did 427hp 696tq.

 

[Alligator]

Those tire rob about 50-75 hp from what you would see stock and looking at your sig, you don't have a lift pump and that could have been an issue too. There are so many variables with every dyno, it could have just been that they couldn't get it to load enough w/o downshifting which screws up numbers. That's what happened with my old 03 on 37's on Edge's dyno, it kept down shifting and my run was 345 hp with an Edge Hot which typically runs 425 with stock tires and a fresh fuel filter.

 

[Kat]

Something tells me they didn't hook your truck up right Unless you think it's down on power?

 

[McRat]

Mustangs are very "operator sensitive". We have gotten wild readings in both directions, depending on who's running it.

Mark off 1/4mi, stand on the pedal, and tell me what it traps, and what it weighs, and I will tell you about how much it's pushing.

 

[Alligator]

Just to reference differences, one month before that run, I put down 375 with the same tune and a stock transmission (built between this run and the Edge run) on Bully Dog's Mustang Dyno. The Edge Dyno was a Superflow.

 

[05DirtyMax]

No i dont think it is down on power it runs fine.I am probably goin to try to order a lift pump this week and get the PPE race valve too.Does anyone know of any good tranny shops in central florida i am wanting to get my tranny done soon.

 

[Alligator]

If your in florida, get Suncoast to do it for you.

 

[vortecfcar]

Like the Pat, Kat and Chad have said - something doesn't sound right. Those torque numbers are alluding to a possible light load on the rollers. When this happens the dyno runs are usually very quick which doesn't allow the turbo to light (~2 seconds or less).

On the other hand, if you think the truck is soft in the power department I'd be glad to look at the tune and log file.

There are a lot of variables ,

Nick

 

[TrentNell]

mustang dyno's seem to be tuff , thats the only dyno i have run on and i thought my numbers were low as well but i had track times to get the real numbers but the dyno was still a great tuning tool i tweaked my tune and did 15+ runs an the end number didnt matter i still new how much i picked up by tweeking my tune .but your run doesnt seem right .

 

[05DirtyMax]

Thanks for the help guys.Pat i will have to weigh my truck i have no idea what it weighs.I just did a straight axle conversion with coilovers in the front.Iwill get it weighed and get back with you on it.Nick this is Carlos buddy Justin that you built the tune for. I will log a run and get Carlos to send it to you.

 

[TrentNell]

its also smart to log your dyno runs so later you can look to see how much boost, rail pressure ect was on the run , i found out why my truck was shifting slow because when i logged it my fuel system couldnt hold rail pressure past 3500-3600 rpm it would get short on fuel and hang shifts .

 

[05' Ditry Duramax]

Do you have gears???

My truck with a K&N FIPK kit and 4" MBRP turbo back kit with no programmer EVER, made 250HP exactly and 496ftlbs at the wheels on a mustang. I have 4:88 gears though.

 

[McRat]

We have a very good ET calculator formula that's based 100% on Duramax Pickup measured data. It's accurate to 2% or better. If you can get me good weight info, and good 1/4 mi trap speeds, you can find out what you are pushing.

All big truck stops have scales, as do moving companies, as well as grain/hay dealers. Make sure you add driver weight.

 

[Buccanoles]

If your in florida, get Suncoast to do it for you.

x2 My first time on the dyno will be there next month

 

[05DirtyMax]

No i still the 373's in it i thought about goin to a 456 though.Yeah i might make the five hour drive up there to check out the dyno day.

 

[05' Ditry Duramax]

No i still the 373's in it i thought about goin to a 456 though.Yeah i might make the five hour drive up there to check out the dyno day.

If you have 40" tires I would strongly recomed going with 4:88 gears. 3:73's will be equal to a 35" tire and 3:73's. 4:88's will be worth the money to do it., 4:56's will be okay but you will like the 4"88's much better.

My truck fell on it's face when I went to 37's. I can't imagine how much of a slug your truck is with 40's. I bet your fuel millage is horrible.