I have not posted anything on this in a while so I decided to write a short story
I do not remember if I mentioned it or not but I bought an 1983 n/a 6.2l with a 700r4 transmission bolted to it for 200 bucks from a guy that was going to scrap it. I used the motor as a way to familiarize myself with the ins and outs of the engine that is in my m998. Although there are extensive differences a lot is still the same, mainly the internals. Either way it was an education stripping it down to heads and just getting an idea of what it entails.
After stripping it down, and loving turbo applications so much since my last two projects have been forced induction gas platforms, I was brainstorming ideas on a turbo setup for the m998. I searched around online to see what others had done to there trucks and what manufactured options were out there. I was shocked to discover that there are no real options available. The only real option is the Banks sidewinder kit and it has to be modified to work for the hmmwv (and as far as turbo kits go that I have seen it is straight garbage, no offense). In most cases I get the classic
"Dont waste your time, it is not worth it. You would be better off buying a full engine and doing a 4L80e swap"........lame. Although I agree to some extent it might be a better option, **** it I just want to give it a shot. I was so surprised that when I googled it I got ZERO pics of custom kits and a TON of center mount factory turbo pics. ALSO LAME.
This is by no means a jab at the people who own those, I just love coming up with new ideas or doing things a little different. At this time I would Like to say I am sorry to you purist guys out there who want to keep things exactly as they were in the military, but having used this trucks in combat I think I have earned the right to do whatever the F*** I want to do with mine
(nothing but love fellas).
On that note here is where my "bubba it up" starts.
I got to looking at the manifold that was on my old 1983 engine that was used on the driver side of the engine. Interesting enough it favored the Banks Power system and I was curious if there was any truth to the manifolds being capable of swapping from one side to the other. I took the manifold, flipped it upside down and backwards and bolted it to the holes on the passenger side of my 6.2. Ill be ****ed, it fit. It was not perfect, the exhaust ports did not line up as straight as I would like but I can fix that. The other problem being that the exhaust 3 bolt flange was facing upwards was also going to have to be corrected.
Obviously the passenger side is ideal for the turbo location due to the large void that is on that side of the engine bay where the air box setup is located. the exhaust manifold also tapers to one end so it does not matter which way it faces, the exhaust will be directed accordingly. The change in direction opens up a large area for the turbo down pipe, which more than likely will have an inside diameter of 3" and depending on space may expand to 4".
CUE ELECTRIC DISK GRINDER!! The direction of my cast iron manifold exhaust flange just will not do so I chopped it off just behind the flange and downward at a 45 degree angle with a 3 to 5 degree inward turn. This will allow a good spot to weld on a 3 bolt 2 1/8" exhaust flange for the crossover pipe. I stood back and took a look at my work and was pleased at how it appeared to allow sufficient space to offset the larger, charge side of the turbo forward of the heads and valve cover. and allowed plenty of clearance for the turbo hot side to clear the fuel lines, injectors, heads, and of course fire wall. Also because of the low flat surface of the manifold it allowed for the turbo to rest just below the opening to the air box to retain its deep fording water system. Checking clearances for glow plugs and injectors around the manifold allowed for a quarter inch of clearance at all points, this is more than enough space considering I will be grinding the manifold smooth, ceramic coating it, and then heat rapping it pre installation.
About that turbo...yea its a chinese hx35 turbo for a Dodge I bought brand new for $160 bucks with gaskets off ebomb, I spent 11 bucks on an iron T3 turbo flange (also china) and another 6 bucks each on a 3 bolt flanges (you guessed it..china). These items are also expendable for test purposes and its not like I cant "go get a turbo motor and a 4L80e" like everyone else right? Moving on..
THe HX35 is much larger than I anticipated but the egt temps, flow, and in and out are superior to the GM model so i am glad I went this direction. I grinded the Dodge style attachment off the end of the charge side of the cold side of the turbo, plugging the holes in the turbo of course to protect from metal shavings flying into the precious turbo, to make it mate up to silicone tubing to connect the piping to the intercooler. I also chopped off an inch of excess steel on the waste gate bracket to help with clearance between the firewall and the engine. To make sure my measurements were as accurate as possible, because every inch is going to count with this size turbo, I drilled out the bolt holes in the exhaust manifold 2mm or so to allow for better alignment of the manifold to the exhaust ports on the head. I then rested the turbo in the area the turbo flange will be located to determine distances, lining up the front lip of the intake side of the cold side of the turbo with the front edge of the harmonic balancer on the engine.
Coming up is the joy of welding a cast iron manifold, fun...
Cannot do that till this weekend so Ill keep you posted on the progress in that department. In the mean time I ordered another passenger side manifold and bolted it backwards and it not only fit perfect but it turned the exhaust flange in the exact direction I wanted it to, so zero modification is needed. I plan to clean it up real good and ceramic coat it and heat rap it as well. The crossover pipe i am making out of pieced together 2 1/8" stainless steel mandrel bent pipe. Not only will it be a shorter crossover pipe but it will have less bends and maintain more exhaust velocity (theoretically) than the Banks system that maintains the existing factory manifold. Once the crossover is welded together and cleaned up it will also be (we know ceramic coated and heat rapped).
I hope that I can make this system work with my truck as the genii pig. I am going to clean my truck up and get some good base dyno numbers (which is going to be hilarious). Then I am going to assemble my kit and using cheap egt and oil temp, as well as boost gauges street tune the truck to 10 psi boost. After that is accomplished I will go run another dyno run and see what the gains are. I will post all my notes and findings for everyone to see and then hopefully offer an affordable, customizable turbo option for everyone. For the purist out there, the objective is to maintain all mechanical setup, to include a built 700r4 transmission with a manual valve body probably. I want to blend it in as seamless as possible. I hate chrome and shiny stuff so likely most of this will be matt black with an exception of the turbo housing.
Another reason I am so **** bent on the side mount setup is I do not like the idea of having all that turbo heat cooped up behind the dog house like that. Theoretically heat will escape a lot easier from the side mounted setup, especially as low as I am trying to mount it. It also keeps the head away from the already failure prone cylinders where the crossover pipe and hot side of the turbo are so close to...just saying. I know some of you follow a lot of the groups on Facebook and I recently posted on there asking if anyone was interested in a turbo kit under 2k and the response was amazing. I hope I can get it together for those that are interested. This weekend I should learn a lot about the problem areas.
Please post your thoughts and concerns. Any feedback will be nice. Thanks!
