LB7 modification: Daily Driver/Tow Duramax

Thanks Rob. I did install a CAT fuel filter adapter, so that's one thing we're gonna check. Would all new injectors rule out the return issue? It's a bummer cause I was hoping to just add the tunes and move on to finishing our drag cars.
 
Did you remove the check ball from the fuel filter head?
 
I'm almost 100% positive that I did, but that's one thing I'll double check. I put new seals in the head too. We're thinking when the one injector was out we ramped up the pressure and it held, but neither of us can remember for sure.
 
Full diagnosis shows the 300,000 mile CP3 to be weak. Ordered a LBZ version and plan get the tuning adjusted accordingly.

OCD is making the tune selection tough, but it's hard to cover the full spectrum of a trucks use from tow to economy to race in just 5 tunes....
 
LBZ injection pump install went smoothly, but it did cause a little lope and some surging. Rob's tuning fixed that right up. Thanks to Rob for the fast turn around on the tunes. I'll update later once it get some seat time on these tunes.
 
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Haven't done much with the truck other than drive and tow a little, however the last tank of fuel I got 19.7 MPG hand calculated. 70% highway @ 77-78mph cruise, the rest on tow/haul doing 50-60mph on hill/curved back roads. The back roads and eastern Ohio highway isn't ideal for mileage so I'm thinking that it could easy do over 20mpg on a flat Texas or NM stretch.

Modifications are Rob's over 100hp "economy tune" , K&N filter, straight piped exhaust, fresh injectors, fresh LBZ pump, and 265/75/16's. The rest is 307,000 mile factory.

Gauges are in. I'd like to put the boost valve in, but know it's going to increase power and I'm trying to wring out every drop from the stock trans before killing it. Therefore I'm planning on installing the manifold and downpipe and track results of EGT's and mileage from those.

I'm still on the fence with a cold air kit. People keep telling me I need one, but I'm just not sure they're worth it.
 
I'm thinking about doing some 'next level' mods, anyone want to take a whack at these things?

1. Transmission rebuild: 312k miles and counting with EFI tunes, everything is still going well, but I should get a grip on what the current builds consist of and what's been proven to be good or bad over the years. It used to just be ATS and Suncoast. Merchant isn't too far from here and the 450rwhp setup is looking pretty good. I'm in central Ohio.

Should I be looking into a co-pilot or this Allilocker? I don't really know what either does, I'm thinking it's mostly just lockup. Are these competition only items?

2. Tie rods: From what I understand there are sleeves or thick body tie rods. Which is a better route?

3. Fuel system: I'm trying to build one. I currently have a Duramax MITUSA pump kit, some lines, a cooler with a fan, and some aftermarket filter heads. I'm not familiar with the LB7 fuel system, does anyone have diagrams of how it works [fuel return, etc]? I'm familiar with the 12v Cummins, but I'm sure it's more primitive than the LB7. I'm thinking I'll have to buy some sort of regulator to keep the input pressure down. I actually don't even know the desired input pressure range...
 
Trans depends on how much coin you wanna spend. With robs max effort stock turbo tunes they'll dyno over 500hp, so build accordingly. Most still use alto clutches, and that's what my PPE stg4 kit uses (alto power packs). If I built it again I would use the Mike L pressure spring instead of a shim in the regulator, and skip the transgo converter valve and just modify the stock one for no knockdown pressure.

Don't bother with the allilocker unless you want to control lockup manually. Latest EFI update covers more converter tables in the TCM including slip inhibit.

Lift pump pressure needs to be below 10psi to keep it from surging.
 
Thanks guys, does anyone know where to look in or around Ohio for a trans build with a reputable warranty/company?
 
Crank it up diesel would probably build one with SC parts instead of ats crap if you asked him. Don't know about warranty. Hell I can help you build it, no warranty tho, but mines been holding great.
 
I'd call Suncoast and ask for Andrew. They can build you one ship it out and then you just send your core back. Their prices are quite good and you'll know it's been done right.
 
Ask Stingpuller (Jeff). He'd know someone local. Those Firepunk guys do seem to have their **** together, though.
 
Does Jeff not build a trans? I can't seem to remember what his shops name is
 
Firepunk...........
I can send him a core if you want to get it done before you pull yours. Mike L. for the parts kit and info. Lavon for build..........in Plain City Ohio
 
Mike doesn't sell kits to just anybody, better off having him build it. Or go to fleece, Danville, merchant, all season diesel. Lots of people I'd have build one before firepunk. Nothing against Lavon but they're not Allison experts. If someone is just going to slap a kit in it, might as well have any trans shop build it.
 
Mike does sell kits and tells you all the specs he wants it built to. He has the newest Suncoast kit and he may offer you HIS PERSONAL NEW kit he has designed.
 
JWhite said:
Mike doesn't sell kits to just anybody, better off having him build it. Or go to fleece, Danville, merchant, all season diesel. Lots of people I'd have build one before firepunk. Nothing against Lavon but they're not Allison experts. If someone is just going to slap a kit in it, might as well have any trans shop build it.
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I would go with Fleece, Merchant or Danville before Firepunk too for an Allison, but the OP asked for a trans builder in Ohio. None of the others are in Ohio. So in Ohio the builder I would trust would be Lavon at Firepunk. I am very confident that he can/could handle anything and building an Allison should be easy for him.

My Allison was built by Jeff Garmon who is also known for his Dodge transmissions and it has held up great with NO problems whatsoever. If quality parts are used a good transmission builder should be able to build you a performance trans with no problems... By the way, mine was built with a SunCoast GMax kit...
 
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