Charge Air Cooler under 400.00$ for all GMT400 trucks & subs

[Twisted Steel Performance]

This is a DIY for a charge air cooler install for less than 400.00$ for the GMT400 body style with a Holset turbo, other turbos will be very close to this, slight changes at the turbo may be needed and at the intake depending on what upper intake you use. This will show the install using the Peninsular Diesel intake.

Because of the length of this post I will make it a 2-3 part posting.

This is how I did it on my 1991 K2500, and is not the only way it could be done, just how I did it, this way uses the mounting locations that are on all GMT400 frames where the front skid plate bolts up from the factory, so that the complete setup could be removed and installed on another truck with ease. The install time is around 6 hours depending on your fabrication skill level and access to shop material’s and tools needed.

I purchased the cooler and aluminum tube bends (I had some straight tubing in stock) and SS T-bolts from eBay, (cxracing) and the silicone hoses couplings from (Silicone Intakes). I already had the aluminum upper intake from Peninsular Diesel and will use it.

I chose to use all 3” tubing as everything in my setup was for 3” already. 2.5” could also be used with no adverse problems if you needed some room for fitment.

The first thing was to remove the skid plate. Before handling the cooler, I covered the fin area with cardboard so not to damage the fins while fitting and fabing the brackets. The cooler comes with mounting bungs welded on the top & bottom, there were also 2 extra bungs in the bag of bolts, I welded the extras to the side(see pics) as it was a better place for the mounting brackets to be. Next, I fabed the brackets that will hold the cooler in place (see pics) and keep it from rubbing on anything. For this I used 2” wide 10ga aluminum and milled slots so that there would be some adjustment if needed (see pics) this worked out very nice and could be easily removed if needed to work on the front of the truck or if the truck was sold.

Continued in post # 2.....

 

[Twisted Steel Performance]

After the CAC was fitted and all brackets were made and verified to work, I removed everything and prepped it all for coating with a ceramic Thermal Dispersant. Test have been done in a controlled environment showing that a CAC coated with this product is 20-30% more efficient at exchanging heat than bare aluminum and 15-25% better than a paint alone. This step is one that most will bypass due to cost, and or you might not think it helps. I was able to do this myself and I think every little bit helps when cooling the charge air in the 6.2/6.5 diesels, or any forced air setup when towing in the hot summer air.

There is some trimming that will need to be done in the drivers side fender wells when fitting the tubing but not much, a sawsall or jigsaw will work well here, no need to remove the fender wells if care is taken and you don’t get in a hurry, you don’t want to butcher things if you can help it, and remember to place some rubber type edge protector on the metal so it doesn’t rub the tubing. The passenger side did not need cutting, just a little tweaking. Aluminum tubing will need to be cut to fit as needed. After cutting the tubing I recommend welding a few short beads on the end of the tubing so that the hoses don’t slide off under boost.

Once you have the passenger side tubing fitted the turbo compressor cover will need to be clocked to point down towards the frame area to meet the tubing, a 45* silicone coupler is used at the turbo to connect the tubing, if your manifold is not wrapped with header wrap, you should consider a heat shield type of cover to protect the silicone coupler.

continued in post # 3..

 

[Twisted Steel Performance]

The drivers side wheel well needed some trimming but nothing else needed moving in my application, some later model trucks might need a little more finesse under the hood to make sure nothing is rubbing, adjust as required. And remember to protect the tubing so it doesn’t rub the wheel well or anything else it may be close to.

As you can see, if done right, there is plenty of ground clearance under the front cross member. There are no places that rub the cooler or tubing, and it can be dropped in a matter of minutes when needed. All this was purchased for less than 400.00$ and is very good quality and can be done in less than a day and you will be able to have something that GM should have done from the start. With lower intake charge temps more air is packed in the chambers for a better burn.

Parts needed --

Use either 3” or 2.5” what ever you want. This list shows all 3” products.

1 - CAC - 27”x12”x3” -- cxracing part# - 1023107000034 - 123.00$
2 - 90* aluminum tubing - cxracing part# - 1005107000352 - 14.38$ ea
1 - 45* aluminum tubing - cxracing part# - 1005107000347 - 12.99$
1 - 75* aluminum tubing - cxracing part# - 1005107000348 - 13.89$
1 - straight aluminum tubing - I had in stock
12 - 3” SS T-bolts - cxracing- 30.00$ ( purchased as a pack of 12)
2 - 45* 3” silicone coupler - Siliconeintakes.com - 16.99 ea
5 - 3” silicone hump couplings - Siliconeintakes.com - 12.99$ ea (depends on size)

This parts list might need to be different for other year trucks but will be very close for all 88-98 GMT400 body trucks & subs.

 

[SS FORCE]

Awesome write up. I've got an HX-35 I am throwing on my rig and this might just need to go on with it. What differences have you noticed with it? IAT's? Lag? Power?

 

[ak diesel driver]

nice clean install. just curious if you going to coat the tubing?

 

[Twisted Steel Performance]

nice clean install. just curious if you going to coat the tubing?

Yes, I ran out of coating product and it hasn't come in yet, I will run them next week with other folks stuff.

 

[tanman_2006]

I'm going to try this coating thing on a few things, maybe my spare manifolds.

Fiancee says she wants a new stove when we get married (next month) and I have an idea for the old one! lol Doubt I can fit a whole innercooler in it though...

Good looking install and nice write up.

Looking foward to some performace readings.

 

[Twisted Steel Performance]

I'm going to try this coating thing on a few things, maybe my spare manifolds.

Fiancee says she wants a new stove when we get married (next month) and I have an idea for the old one! lol Doubt I can fit a whole innercooler in it though...

Good looking install and nice write up.

Looking foward to some performace readings.

Do your research, it isn't a spray and bake kind of product at all, and unless you are a dealer you can't even purchase the product, lots of prep in it... but you can learn to do it.

 

[tanman_2006]

I didn't figure it was that simple, never is. I just figured it is worth a try if I have a spare oven to modify. IIRC you (or someone) posted a how to on making an oven for this type of thing.

When I get closer to D-Day you will probably hear from me lol

 

[Twisted Steel Performance]

I didn't figure it was that simple, never is. I just figured it is worth a try if I have a spare oven to modify. IIRC you (or someone) posted a how to on making an oven for this type of thing.

When I get closer to D-Day you will probably hear from me lol

You CAN use a electric oven if the parts will fit in it, I use one for small things that will fit.. the big oven costs $$$ to fire up...

The prep is where the time & knowledge is needed... none of the products will work or stick if the prep isn't right.

 

[NVW]

Nice install, looking at your pics it wouldn't work on my truck. I have a hydraulic pump on the drivers side under the alt.

 

[Twisted Steel Performance]

Nice install, looking at your pics it wouldn't work on my truck. I have a hydraulic pump on the drivers side under the alt.

My PS pump is under the alt.... what kind of pump is under yours?? The tube is not even close to the PS pump on mine??

 

[btfarm]

Nice write-up Chris. :thumbsup: I fixed a couple of spelling errors but otherwise it looks great. I'd kind of like to move it to DIY though with the discussion part in 6.5 performance land. Not real sure how that should go.
In any case, thanks for the excellent tech contribution!

EDIT: The DIY posts from above are now in the DIY section and comments are here. If there are technical additions to this then I will be happy to add them to the DIY

 

[NVW]

My PS pump is under the alt.... what kind of pump is under yours?? The tube is not even close to the PS pump on mine??

It's a 5 gpm hydraulic pump for the bale deck, I guess it is under and to the side to be correct.

 

[1999gmc]

Man, prices haven't changed much. I think I paid about that 8 years ago when I did mine. Only difference is I welded my pipes to minimize silicone joints. But, nice install. I think it's worth it. Slim and turbine doc told me I don't need it with the ATT, but when I installed the ATT and it fit better to that than it did with the GM8. I decided to just leave it instead of cutting my stock intake or plumbing it to my peninsular intake. I have never felt the ATT was laggy or anything with it, so I just left it.

 

[Twisted Steel Performance]

Man, prices haven't changed much. I think I paid about that 8 years ago when I did mine. Only difference is I welded my pipes to minimize silicone joints. But, nice install. I think it's worth it. Slim and turbine doc told me I don't need it with the ATT, but when I installed the ATT and it fit better to that than it did with the GM8. I decided to just leave it instead of cutting my stock intake or plumbing it to my peninsular intake. I have never felt the ATT was laggy or anything with it, so I just left it.

Yep, I would have welded them but I don't plan to keep this truck forever and I might need to swap it all out someday... or remove it & sell it???

And I can't see why it wouldn't help with any turbo application, cooler air is more air anyway you look at it.. I don't see any lag on mine either....

 

[Turbine Doc]

Yep, I would have welded them but I don't plan to keep this truck forever and I might need to swap it all out someday... or remove it & sell it???

And I can't see why it wouldn't help with any turbo application, cooler air is more air anyway you look at it.. I don't see any lag on mine either....

I've been MIA from the forum for a while been dealing with some extensive issues at home with wife's health; a little insight on the lack of IC recommendation. I've never said that an IC was not a worthwhile venture I had one for years (I still have it on the shelf) it was required IMO when towing with the GM turbo.

Additionally in spite of what some "unbiased individuals" will tell you at other forums, the lag when combined with the ATT was not prohibitive regardless which gears are used in the final drive be it 3:42 or the 3:73s 2wd or 4wd, some "gommed up" onto a statement I had made in the original ATT thread that I removed mine and felt a slight delta in spool up.

NEGLIGIBLE delta and unless you were the owner of the vehicle with miles of seat of pant time in the vehicle I dare say anyone else would feel the delta IC'd or non IC'd.

Both of my 6.5s are sans IC because of the pressures that they operate from a boost standpoint 99.9% of the time all speed/load demands are met with 6psi or less boost, some would argue that doing more with less boost pressure is not possible but it is. War Wagons most recent information demonstrates this as do my day to day operations since 1st installing my turbo, but not going there in this post.

I have a WMI setup that has not been installed on the truck, which is where the IC was originally installed and may go back if the WMI proves to be too much of a PITA to keep up with filling water etc.

There is a convention of thought relayed to me by Bill Heath that the design parameters for combustion chambers we have in the 6.5 for economy actually like around 150F IAT assisting with ignition.

Most times I'm running below that non IC'd hence recommendation that IC or charge air cooling is not a requirement with ATT, and the expense and or work to add in charge air cooling can be added later after other performance items have been satisfied depending on ones budget.

At upper levels of boost 10+ psi (I'm capable of 100mph on a cool day with that boost running empty BTW) is where charge air becomes beneficial & necessary, since I drive most times 75ish with about 6 psi boost charge air cooling is not required.

When I light tow 6000-8000# same speed unless doing a long pull up grade @ same speed may get me to 12 psi and elevated IAT 200ish.

Mostly I'm 6-8 psi 170F IAT max. or so; heavy tow 18K# on a hot day, is where you need charge air cooling of some sort, I've not had to pull that kind of weight on a hot day since removing the IC. I was going to run a special WMI setup for test but just have not gotten around to it as of yet waaay too many things on my plate last few years to do much with it. If going for a race or max dyno # you may want some charge air cooling then.

So bottom line charge air cooling is beneficial and only way to make max HP from the turbo, but MY CHOICE to remove the IC was purely academic reasoning that I didn't need it most of the time, and NOT BECAUSE I was losing performance as a result of running the IC.

Emphasis added for benefit of those elsewhere that think they know as much as they pontificate about on why things were done making ASSumptions as to the why things were done.

No venting directed at any in this thread thus far, my apologies to OP, I just read for the 1st time the "unbiased" comparative report of turbos at another site and got up on governor a little over the many untruths reported there.

 

[DieselSlug]

I just listed the Cummins intercooler i bought 3 years ago on c list, your install looks really nice! I want to do this someday, but i have a Fisher plow pump to the South East corner of my alternator. I also have Fisher plow brackets between the frame rails, so it will take some effort to get it to fit down there. Again nice job accompanied by a good write up!

 

[Turbine Doc]

I just listed the Cummins intercooler i bought 3 years ago on c list, your install looks really nice! I want to do this someday, but i have a Fisher plow pump to the South East corner of my alternator. I also have Fisher plow brackets between the frame rails, so it will take some effort to get it to fit down there. Again nice job accompanied by a good write up!

A lot of discussion at the 6.5 expert site (NOTT!!!!!) where Steaksauce lives and peddles his wares to the uninformed 6.5er about "risks" of a under bumper mounted IC; I ran mine there for years without any issues at all.

I looked at "cooling stack mounted ICs" myself but since the 6.5 is flow challenged already I opted to not go the in grille stack mount, possibly with retuned fan clutch and other cooling mods it may not be an issue as an add on, with stock setup I'd recommend not going there, works for trucks/engines designed from "get-go" to have a IC in the grille, for the 6.5 not so much IMO since GM did a marginal job initially getting air through the rad & ac condenser.

Add in things like plows IMO would make things "interesting" and maybe a WTA or WMI a better option

 

[DieselSlug]

A lot of discussion at the 6.5 expert site (NOTT!!!!!) where Steaksauce lives and peddles his wares to the uninformed 6.5er about "risks" of a under bumper mounted IC; I ran mine there for years without any issues at all.

I looked at "cooling stack mounted ICs" myself but since the 6.5 is flow challenged already I opted to not go the in grille stack mount, possibly with retuned fan clutch and other cooling mods it may not be an issue as an add on, with stock setup I'd recommend not going there, works for trucks/engines designed from "get-go" to have a IC in the grille, for the 6.5 not so much IMO since GM did a marginal job initially getting air through the rad & ac condenser.

Add in things like plows IMO would make things "interesting" and maybe a WTA or WMI a better option

What scares me with the water stuff is the cold temps here. My ac condenser is removed and i have an hd clutch. But i see how the plow would hurt a lot!
Sorry for the thread hijack.