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noobbuilder

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Ok i have an 07.5 GMC sierra 2500 Duramax Allison. I have EFI live with the switch, 4inch turbo back MBRP exhaust, EGR delete, and banks intake. Looking to run er up to about 700 horse was looking at the ATS trans to replace stock Allison Good idea or is there a better one out there. Also was looking at the Aurora 7000 twin turbo kit to utilize my stock good idea or bad. Not sure if i need a lift pump or just get a high perf cp3. Whats your thoughts good idea or not any better parts than what i suggested want to keep the stock turbo and injectors because of cost to replace them. Truck is just a daily driver and trailer puller pulls 24k pounds like a dream as it is but just want alittle more power.
 
1) 700hp in that truck will end its life quickly
2) Do not buy anything with the letters A,T,and S in that order on it.
3) You will need a lift pump
4) For 700hp you will need a XX% over cp3 or dual stock cp3's

Where do you live? There are several extremely good Allison builders around the country that can build your current trans to hold whatever you desire, going that route will save you money up front and down the road compared to going with an ATS.

650hp is about all the stock cp3 and stock injectors will give you (depending on the condition of your Cp3)

And for the twin kit, there are much better and more cost effective kits on the market then what ATS has available. Better performing and cheaper, thats ano brainer.

Home - Wehrli Custom Fabrication
Huron Speed Products, LLC


Those are just 2 of the extremely talented fabricators that make kits for these trucks.
A stock turbo over an s475 (most basic kit) will do you very good. It will spool awesome and provides enough air for 750ish hp.
 
FWIW, if you do decide you want 700hp and have to upgrade the injection pump, go with dual fuelers (2 stock pumps) instead of one modded pump. Reliability with the 2 stock pumps will be greater than with a single modded pump.
 
Ok first off i live in southeast montana. Next why is 700horse killer on my pickup and what is wrong with ATS stuff? Want to make sure i have enough fuel is a lift pump good for 700horse or do i need dual fueler. What is your recommendation on a twin setup using stock turbo.
 
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Well these motors were engineered to operate at a max of 300ish hp so naturally when you try to double that, plus some, things break. Particularly your rotating assembly lol. LMM pistons hate heat and stock dmax rods turn into noodles around 600-650hp. I know of several duramax's with stock internals running close to 750-800hp, but a lot was done in the tuning and they are not running twins that make peak torque way down low in the rpm range. The super low rpm torque these trucks are capable of is what kills the rods. If yo run a large single and keep torque out of the tune until 2200ish rpms, it may live for a while above 600hp. I can push my truck past 600hp if I want but I only do that once in a while. The rest of the time I'm cruising around with about 400 at the wheels.

ATS is over priced garbage. Ill comment again later and show you a thread on another forum that is nothing but reputable Allison builders.
 
As for twins. Contact the 2 companies I provided links to above, they are IMO hands down some of the best fabricators for duramax trucks. But your stock turbo over an s475/96/1.32 would work great for your goals.
 
Listen to what Sean said. First order of business should be finding someone to build the transmission, install a lift pump, and get some max effort stock tuning on the truck. Most people that say they want outrageous horsepower numbers have never even felt what 500hp and 1000lbft will do! Once you have the basics(which you would need to go further anyways) see how you like it and go from there.
 
Also, I just reread this and saw it pulls a 24k lb trailer and just needs "a little more power" See where the stuff I posted above gets you and then if that isn't enough, look into an S475 over stock twin kit. They make good power and spool great for towing. Towing at 700hp will grenade pretty much any motor, regardless of how built it is.
 
Iam thinking iam close to or above 500horse as it is its nice but want alittle more i was wanting 700 on my highest setting with efi live other setting less but with rods being a weak point i may just say the hell with it.
 
Definitely a good idea to not push it that high. From what I have seen fixing duramax everyday, anything about 650ish+ has a terrible and costly ending without extensive preventative bottom end back up.
 
noobbuilder said:
Iam thinking iam close to or above 500horse as it is its nice but want alittle more i was wanting 700 on my highest setting with efi live other setting less but with rods being a weak point i may just say the hell with it.
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If you are running a stock trans and it isnt slipping, you arent making 500hp. Also hard to do without a lift pump. Join duramaxdiesels.com and do some reading. There is a lot more dmax info there.
 
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