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H1 Hummer Cummins Swapped

Sand

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Location
Canada
And the fuel tank is getting spaced down. The driveshaft only barely cleared the fuel tank stock. One inch lift has it running right on the sheild bolted to the side of the tank. To lengthen the upper tank straps I need to drop the tank out. I'm looking tomorrow at possibly twinning the tanks together to get rid of the Pollak tank selector valve or possibly running a pair of valves in parallel to cope with the airdog flow requirements without burning up a 800 dollar fuel pump/filter unit.
 

Will L.

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Boulder City Nv
Rip out the stock selector valve, yes. But idk about pulling from both at same time - sounds like issues to me. Because if it pulls from both equal, and returns equal, tank sizes would need to be equal.

My 95 has no aux tank, yet. I am adding one and will use a stock LP from it to the main tank. When I see my main tank at 1/2, I will flip a switch to drain the aux tank into the main. Only running supply and return to main tank.

What is return line size for that set up, 1/2” or 3/8”?
Any of the parts you remove, put up for sale. Might be a while but someone will buy it.
 

Sand

Well-Known Member
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Location
Canada
Just topping up with a transfer pump from the aux. A good idea.
The parallel selector valves would pull and return to only one tank at a time. Just twice the available flow rate of a single. But it does sound fiddley with a bungle of hoses and "Y" fittings. Problematic.
 

Will L.

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If a rig is mostly stock, then it’s better to keep it that way. But once you make major mods, correct all the nonsense crap imo that has problems or unnecessary expense.
 

Will L.

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I believe he is referring to insulating the intake and exhaust lines for heat. You want to trap the heat in the exhaust and out of the intake.
Header wrap works great for exhaust exterior, but can trap moisture in and cause quicker deterioration, especially if you put it under water frequently.
 

FellowTraveler

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Nature Coast
Wrapping the CAC/IC piping was what I mentioned perhaps I was not clear, wrapping these pipes keeps heat soak from exhaust and engine bay at bay........

If using a small turbine cm2 size your EGT's will be constantly higher and radiant heat will soak into charge air cooler aka; inter-cooler than using say a 14 cm2 or larger turbine housing.

Ceramic coating your exhaust down pipe and turbine housing inside and out will beat the radiant heat back and prevent cracking in high EGT applications as exhaust wrapping goes its known to corrode and cause heat cracking on un-coated headers on mostly N/A applications.

My downpipe is ceramic coated inside and out, I just wet wrapped it with pumice (natures micro balloon's) impregnated wrap a few days ago soon I will heat it real good w/torch and seal the wrapping with extreme high temp silicone spray the result will be a downpipe I can touch w/o getting burned when it hot.
 
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Sand

Well-Known Member
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Location
Canada
I'm sure an intercooler would fit. It's the top of the cummins that's just too close. A stock TD 6.5 hummer has a factory 1/2" lift and the intake only just clears the base of the windshield.
If you keep the same driveline position as the 6.5 the cummins is just a bit taller and needs just a bit more.
 

Will L.

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The cooling stack (referred to in engineering community as btur - British thermal unit(s) rejected) is all of the components that are for rejecting the excess heat produced in the drivetrain. Engine coolant radiator, transmission cooler, power steering &brake power booster cooler, a/c condensor and the cooler for the turbo.

On Hummers, there are currently 2 aftermarket charge air coolers being produced, and 1 ‘factory authorized’ unit.

Both aftermarkets are priced within a few dollars of each other at high enough prices that anyone can have a custom built one for the same price if they do some shopping around.

The only factory unit is only sold with a complete stack from AVA. Almost a year ago I spoke with them about it and some other stuff they have. Almost 6 grand. Fittings, seals, and hardware are extra.

The additional required body height for the cummins makes playing with the stack much nicer in modifications. Just keep
in mind the better air seal to hood using the foam vs the rubber flap, and make sure the foam is proper type for the heat.

A part number: for the ic that fits the hummer cooling stack? Each hummer parts reseller uses there own number, some just use the name.
You have a Hummer also?
 
Messages
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Location
Orange, California 92867
You have a Hummer also?
I have a Savana van and currently the inter cooler is mounted below the radiator where the air dam is cut open to allow the air flow to and through it.

Since my A/C condenser is on the side - I was considering getting a thin and larger inner cooler to place where the A/C condenser is often found

I looked at the Duramax inner coolers and they have outlets pointing perpendicular and I was trying to find one with a core thickness that is thin . . .
 

Will L.

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Boulder City Nv
Ok, the hummer sizing is WAY off from the gmt400. I think van front isn’t way different from trucks.
I still have dodge cac for a gmt project I went a different way with. Iirc someone on here did a write up doing theirs with a dodge unit.

Have you looked into water to air? They are more expensive but work much better per square inch.

Also really consider having the stack coated with tltd by Chris of Twisted Steel. Independent testing shows over 30% more heat rejection. So that is like making it 1/3 bigger.
 
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