Hi guys,

I've got a bone stock LB7 and I was wondering what you guys recommend for the first round of mods. I was thinking 5" straight exhaust and EFI Live.

Get a PPE boost valve there only $30. it will help drop your EGT's

Extra filtering of fuel to maybe help injectors to last longer.
Lift pump to take a load of the CP3.
Trans-go shift kit.
Easy on the tuning for stock Allison even if one adds a shift kit.

Brian

Would the PPE boost valve be noticable when stomping the throttle wide open compared to not having one on it? How many seconds faster might my truck be with the PPE boost valve from 0 to 60 mph? My truck is also bone stock and maybe in about year or two start to add a built trans and EFI Live. Thanks.

Moved to other performance discussion

Thanks for all the replies! I've got the EFI Live on the way and I'm going to save up for one of George's tranny rebuilds since he's not far from me. Is the stock Allison really that weak?

What mods can I do to put it at it's limits?

Its not really weak, it was just never built for a performance/racing application. As for how much it can take, that's a loaded question. You could put a 200 HP tune in it and drive cautiously and never have an issue, or you could put a 90 HP tune in and limp it easy with a heavy foot, so driving style plays a huge part. Most say that 75-90 HP above stock power levels on a stock tranny is the limit.

Makes sense. Can I get 475hp/1000tq with just an EFI Live tune and straight exhaust? I won't be drag racing this thing. Just looking to have the power there, probably on a roll.

Yeah, you probably could, but I'd say your headgaskets would be at risk (again, depending on driving style and boost). You'll need a lift pump to get to that level, the CP3 can't pull that quantity of fuel by itself, plus it doesn't hurt to have the extra fuel filtration some of those provide

What lift pump do you guys recommend?

I've been partial to Kennedys setup, Airdogs are wildly popular and include filtering, Raptor is made by Pureflow (Airdog) and is very affordable, but does not include filtering

I was checking out Kennedy's site. Am I looking for the "pump-filter combo"? It looks like two pumps and a filter? Looking for their best setup. I don't mind spending a little extra coin to never worry about it :)

Thanks for the replies!

Is it his Mega Filter setup? His pumps are nice, ill be getting his twin setup

I'm not sure.. here take a peek:

http://www.kennedydiesel.com/detail.cfm?ID=489

That's something different then I was thinking, better actually. His pumps also are a flow-thru design, which means if the pumps should stop for some reason the truck will still run

Don't forget to do an air horn. ;)

I saw the write-up on Dmaxcentral - is it a dyno-proven mod that shows gains?

Also, my truck is a California truck. If the EGR is working perfectly, is there any reason it should be deleted?

i just put a down pipe from profab on, a full bore manifold and did the intake horn mod. it's been alot of fun to drive. not the power gains you'll get from a lift pump but it's a couple hundred dollars cheaper. they will also help the truck breath alot better if you plan on a better turbo and more fuel.

Any feedback on the air horn?

Also, do the MBRP turbo-back kits come with the downpipe?

No, the down pipe is sold separately from the exhaust kit. An aftermarket exhaust will bolt up to an OEM down pipe, as well as vise versa

Okay that's what I thought. It just confuses me when they use terms like "turbo-back" when in reality it is not turbo-back.

Does anyone make a 4" downpipe, other than TTS?

A 3" downpipe is all you need

I found out the TTS pipe is actually 3" anyway.

There's not really any room to fit a pipe bigger then 3" anyway. RDL makes a really nice downpipe

I've been more than happy with my rdl down pipe had it on for a little over a week now.

There's not really any room to fit a pipe bigger then 3" anyway. RDL makes a really nice downpipe

mines bigger than that & could have gone bigger if I wanted to but no point, the IHI can only push so much air

Which down pipe are you using?

custom

Awesome, do you have some pics? Who made it for you and what size is it?