I am rebuilding my 1985 6.2L VIN C, Engine RPO-LH6 into a VIN J, RPO-LL4 and was wondering if the only difference was the injection pump? Also I found a website that has remanufactured military 1 ton injection pumps & injectors for the 6.2L. Would they be better than an ordinary 1 ton pump & injectors? Has any one heard of a twin turbo system for the 6.2? Is there any other performance parts for the 6.2 other than a turbo system? Any help in these areas would be greatly apreciated. Thanks.

You can run with a higher pressure injector with a high flow nozzle.. IE build a 6.2L injector up to work like a 6.5L Marine.. you can also take your pump to a fuel shop and have them crank up the flow on it 10%. It will definitly give you more power with a little less gas milage.. combine with the injectors. Advancing the pump timming a little will help along with the standard intake exhaust stuff. LP injection works as well but the company can't recomend thathttp://www.dieselplace.com/forum/smileys/HiHi.gif

Thanks Diesel-Direct, I will definitly look into doing that.

project 6.2L,


Injectors are important but it's the pump that determines how much fuel is injected per injection event, not the injectors. The DB-2 can be turned up(fuel, upper rpm advance) by removing the cover on the middle of the drivers'side of the pump. Insde is the fuel metering screw, 5/32" allen iirc. Screw in for more fuel/upper rpm advance and out for less. 1/4-1/2 turn "in" is plenty unless you put on a turbo or supercharger and an intercooler to justify so much fuel.Edited by: quantum mechanic

quantum mechanic,


Does adjusting the metering screw turn the fuel up all together or just at high RPM?

Both fuel rate and upper rpm timing are increased/decreased with the metering screw. Push the pump to the driver's side for advance. 1mm=2 deg

Thanks for the info quantum mechanic, it will be very usefull in my "Quest for Power" you could call it. I noticed in the description of your truck you have ported intake & heads. Is this a possible idea for my 6.2L? Did you notice any performance gains?

My truck had an EGR castweb that choked my intake off. It made a difference to remove that I'm sure. My heads have yet to be ported but I think if done right, it could help build more power.

quantum mechanic,


So if I were to get the 1 ton intake, which has no EGR system, would that do the same thing in theory? And what about polishing my intake and exhuast ports would that be an idea for a little more breathable engine? If so, do you have an idea what that might cost?

HD EGR-less intake would certainly be best, I'm sure there is something to be gained from porting the heads, but I couldn't promise you that you would notice a difference. Go with Hi-Pop 6.5 injectors. The screw that QM referred to earlier is actual the leaf spring screw, turning this in actually allows the plungers inside the pump to open further and pump more fuel. I would say since your going to go N/A, that 1/4 turn is about as far as you want to take it, above that, you won't make any more power, just leave a trail of black smoke and use more fuel.

project 6.2,


It would cost a mint to have it done or you can do it yourself. It just depends on what your power to dollar ratio is. Turbos and intercoolers cost money and if you arn't going to use them the porting has limited value in the N/A 6.2.


19:1 pistons would only be "worth it" if your going this route also, as it's applications are turbo/intercooling related.


Build what you intend to drive. gmctd is an example of this, as he planned out and built his 6.5TD himself, as well as many other mods.

Texas Diesel Guy, About these HI-POP injectors do they increase power that you can notice? I have read people writting abou them in this forum but not to much info on them. Where would I find some and for what cost(roughly)


quantum mechanic, I am using this forum and the information that it has to aid me in that. The info I get from all of you is very helpful and apreciated. I have come to this conclusion so far , "Stay Natural"(for longevity) with headers from www.stansheaders.com (http://www.stansheaders.com) , a Carter electric fuel pump since it is diesel compatable and at the right pressure,my RACOR fuel filter system on the suction side, Stud Girdle kit ,overhaul kit and rebulit heads from www.dieselservices.com (http://www.dieselservices.com) , AFE air filter, some sort of HO Injector pump and injectors,glow plugs on manual switch(push button) and an EGR-less Intake. All infront of a manual 4 speed in a 1972 Chevy pickup with a Dana 60 rear end (4.10 gears but probobly changing to higher) Any sugestions will help me in this prosses and apreciated.

Keep us posted on how it's going and we'll tell you all we can. You have an idea of what you would do and that's a good start.