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I've decided to do a Cummin's conversion

FellowTraveler

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Thread starter #284
WOW, aside the time I have invested in this conversion all the little issues and additional expenses pile up quickly but considering I've been doing it and not some shop I'm saving BIG BUCKS..

I'm trying to get an obsolete cooling fan bracket from a 91.5 to 93 CAC/IC Ram Cummins because it will give me more space to install a 3 core radiator if not I'll have to stick with the two core unit....

I'll be running a big honking air filter BHAF w/prefilter sock until I can get the air canister & snorkel fabricated.

Hopefully this week I can tow the Burb around some to make sure suspension is settled so I can measure for driveshaft.
 

Nosferatu49534

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WOW, aside the time I have invested in this conversion all the little issues and additional expenses pile up quickly but considering I've been doing it and not some shop I'm saving BIG BUCKS..

I'm trying to get an obsolete cooling fan bracket from a 91.5 to 93 CAC/IC Ram Cummins because it will give me more space to install a 3 core radiator if not I'll have to stick with the two core unit....

I'll be running a big honking air filter BHAF w/prefilter sock until I can get the air canister & snorkel fabricated.

Hopefully this week I can tow the Burb around some to make sure suspension is settled so I can measure for driveshaft.
BHAF [emoji23][emoji23][emoji23][emoji23]
Glad your getting close. [emoji3]
 

FellowTraveler

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Thread starter #291
What filter are you planning on running? I noticed an improvement over the Donaldson B085011 when I switched to the AFE replacement which is 72-90058.
I was thinking Donaldson but if the AFE is better I'll do that. I'm not using an air box for this because it will not be in there for very long and will be right under my hood scoop so I suspect plenty of cooler air at speed.

Later, I'll be using a rather large 10" diameter x 22" long canister that flows enough for 400 hp, it will have a cobra head intake runner to the turbo compressor then a 5" to 6" oval snorkel.
 

n8in8or

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I was thinking Donaldson but if the AFE is better I'll do that. I'm not using an air box for this because it will not be in there for very long and will be right under my hood scoop so I suspect plenty of cooler air at speed.

Later, I'll be using a rather large 10" diameter x 22" long canister that flows enough for 400 hp, it will have a cobra head intake runner to the turbo compressor then a 5" to 6" oval snorkel.
Sounds good. I noticed a 3 or 4 psi (I don't recall at the moment, but I think I went from 28psi to 32psi....which freaked me out!) increase in boost when I switched from the Donaldson to the AFE. That was the only change I made, so that told me that the Donaldson was a restriction.
 

FellowTraveler

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Thread starter #293
Many for some reason still think you must retain the stock 6.5l ECM for the guages to work which is as false as can be as the ECM does nothing in a diesel for the cluster. If you retain the ECM and stock wiring, then yes you would have to provide the ECM with a crank signal. But it's FAR easier to just run the A/C request to a relay and install a WOT cutoff switch if you want one. Just make sure and keep all your safety switched wired correctly as GM did it really screwy stock. I would reccomend starting over and do your own wiring for the safety switches.
FERM, I seem to remember something about changing out the proportioning valve to eliminate ABS, I disable it anyway when I go off road and drive in snow any thoughts?
 

FellowTraveler

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Thread starter #294
Sounds good. I noticed a 3 or 4 psi (I don't recall at the moment, but I think I went from 28psi to 32psi....which freaked me out!) increase in boost when I switched from the Donaldson to the AFE. That was the only change I made, so that told me that the Donaldson was a restriction.
Good info are you using a filter sock too, or?
 

THEFERMANATOR

FRANKENBURBAN
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Staff #296
FERM, I seem to remember something about changing out the proportioning valve to eliminate ABS, I disable it anyway when I go off road and drive in snow any thoughts?
Find one off of a 93 2500 pickup and you should be good to go. All the gmt-400 suv's got 4 wheel abs I believe, but pickups didn't until 94/95.
 

THEFERMANATOR

FRANKENBURBAN
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Staff #298
93 pickups only had rwal. They called it abs, but it was only for the rear wheels. It used a regular braking system, but had a dump valve in the rear brake line. If the rear brakes locked up, the valve open and dumped pressure to a built in accumulator was all. It wasn't much of an abs system, but it was enough for them to call it one.
 

FellowTraveler

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Thread starter #299
93 pickups only had rwal. They called it abs, but it was only for the rear wheels. It used a regular braking system, but had a dump valve in the rear brake line. If the rear brakes locked up, the valve open and dumped pressure to a built in accumulator was all. It wasn't much of an abs system, but it was enough for them to call it one.
OK; It's kind of like the old aircraft systems I get it.......as always thanks.
 

FellowTraveler

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Thread starter #300
Hello everyone, I've been playing catch up with this project and finalizing the cooling system heat circuit and the torque converter heat exchanger circuit and have a question.

All my previous chevy/gmc diesels had some sort of hot water shut off valves incorporated into the heater hoses but this 99 gmc just has the heater hoses plumbed to both heater cores w/o any shut off valves and truthfully I never had issues with the hot water flowing through the heater cores during hot weather and AC was so cold in the past I actually had to blend heat in to be comfortable and since I'll remove the ECM and wire the AC like FERM suggested do I need hot water shut of valves or?
 
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