GMT 800 turbo kit for a Gmt400 help please!!

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Poondart

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Disney

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On3 is great, and the intercooler can be mounted creatively if you have to. Top mount with a cowl hood, for example.
Literally the first time in my life I've ever read that statement. I've thought about it and compiled a list of things that must also be great.
Harbor freight sockets
new package of crackers where every one is broken
alcohol-free beer
paying $5/gallon for regular gas
being in a plane crash
Portland peaceful protests
herpes
running your knuckle into the grinding wheel
 

1989GMCSIERRA

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You’re probably going to have to get very creative and may have to do some fabrication or modification. You’re trying to put together a kit for a engine in a body style that were never designed to be together and you’re try8ngbt9 throw a mechanical device that was never offered.....you're completely in the youre n your own fabrication world. you may have to use a smaller different shaped intercooler that fits behind the bumper. There is space down low behind the bumper. You may need a wider narrower cooler like one off a import. You might have to cut the inlet a outlet and make new inlet avd outket in a different position. . You may even need to cut one and reweld it to fit. You may need to cut the bumper to allow for air holes
 

1989GMCSIERRA

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Well, that’s what I was looking for, but this one is a bit overpriced on everything. Looks pretty quality though. I may just have to do some welding myself, or keep searching for budget kits.
Thank you for sharing.

they did all the R&D work, the manufacturing, stock advertising and sales. If someone wants a plug and play kit.....It’s not gonna be cheap.

how much time and money is it going to cost for you to fabricate a kit? Just to buy the kit is gonna run 2k. Then you need to modify the hell out of it to make it work
 

Christian Steffen

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Well, that’s what I was looking for, but this one is a bit overpriced on everything. Looks pretty quality though. I may just have to do some welding myself, or keep searching for budget kits.
Thank you for sharing.
.
IMO you're going to be money ahead doing it yourself, just plan to do new exhaust. Intercooler mounting/ routing will be the biggest PITA. Perhaps you can hide it behind your tube bumper? Maybe cut a larger air hole and install some sort of screen to keep out rocks?

Perhaps there is more room in the grille of a half ton, but i put a little intercooler in the grille of my truck and had to trim quite a bit.
 

skylark

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I'll be running an air to water intercooler on my 6.5 due to the issues above. I don't want to take a chance on a low mount intercooler. I personally think that it will be much easier to mount a long and narrow heat exchanger behind the grill with 3/4" water lines running to a reservoir mounted under the bed.
 

Supercharged111

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The problem with a kit like that is the fact that turbo intercoolers weren't offered in any of the diesel GMT 400 trucks. There's just not much real estate between the condenser, trans cooler, and grille
Now, where there's a will, there's a way. But not for cheap, and not without reinventing the wheel.
So plan on mucho $$ in attempts, or accept losing the intercooler.


Or mount it ugly... in front of the bumper/grille

I'll be running an air to water intercooler on my 6.5 due to the issues above. I don't want to take a chance on a low mount intercooler. I personally think that it will be much easier to mount a long and narrow heat exchanger behind the grill with 3/4" water lines running to a reservoir mounted under the bed.

If you remove the spars from the core support, move the AC back, ditch the middle support that reinforces the hood latch, a front mount fits. Requires relocation of the trans cooler too, but they do fit this way. Also requires hood pins, but there are elegant solutions on the market for that.
 

skylark

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If you remove the spars from the core support, move the AC back, ditch the middle support that reinforces the hood latch, a front mount fits. Requires relocation of the trans cooler too, but they do fit this way. Also requires hood pins, but there are elegant solutions on the market for that.
I've seen a couple of versions of this and I didn't like the results. I've also seen it done without hood pins but I wasn't impressed.
 

Supercharged111

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I've seen a couple of versions of this and I didn't like the results. I've also seen it done without hood pins but I wasn't impressed.

No? IIRC you just flip the moints to move the AC back, keep the radiator where it is, and shove an IC in front. My friend did it and it doesn't look all janky. I'd even be inclined to do it that way with W2A to fit a decent sized heat exchanger up front. Having had a crappy W2A in the past, I'd engineer it much more aggressively were I to use it again in the future.
 

Poondart

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Thanks for the comments and ideas guys. Much appreciated.

I contacted on3 performance(the kit linked in the OP), they were not all that helpful in telling me what could be used and what couldn’t be used in their gmt800 single turbo kit.
They did however tell me that plenty of folks have used their kit on gmt 400’s with slight modifications. They just couldn’t tell me what modifications were needed.

I also found another “kit” from LSX everything. But their kit says 94-2007, which confuses me a bit. I am waiting on a response from them for clarification. Link below

Again, thank you all for your input and ideas
http://stores.lsxeverything.com/1994-2007-gm-truck-ls-turbo-kit/
***Edited***
After doing some research on LSX everything. I will definitely not be using them, many complaints about their products and services. BUYER BEWARE!
 
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