p-pump a first gen motor?

Apmaw55

Apmaw55

Dozer
Joined
Aug 29, 2012
Messages
147
So I want to p-pump my first gen. I rebuilt the hole motor last year and I actually put a vp cam in it with #60lb valve springs. It had 90 horse injectors and a hx35 with a ats manifold so i put those back in. It only builds about 27lbs of boost now So am i not getting enough fuel or just some where I just have to much?
 
A buddy of mine tunes and rebuilds ve pumps. So I had him tune it and his dad's and few other guys trucks still run way better than mine. They also build bout 45lbs of boost
 
Something is wrong. Did you adjust your wastegate?

To ppump, you need timing case and ppump hardware.
 
No I haven't messed with it. Before it would run 45lbs of boost easy. That was with a automatic in it. Broke the flywheel so I put a getrag in it then it broke the cam so I rebuild the hole thing but put everything back together just added the 60lb spring s and a vp cam

I still need the case for the p-pump but other than that I have everything else to do it. But should I find a p-pump block or would a ve block be fine?
 
900 cruzing 70-75 with my skid in the back. The skid weights about 2,200lbs

What about the fuel bowls?
 
You should be able to way over fuel an hx35 with a ve. If you're not looking for big power, I'd just figure out what's up with you're current setup.

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Ok. I have heard that I might be burning my self with the the vp cam. Know anything bout that?
 
The vp cam may not have a fuel pump lobe for a mech pump but should not negatively effect performance. I assume since you are running a ve pump then the cam you are running is either equipped or you are running an electric pump. The fuel delivery needed by a p pump are much higher than the very needs.
 
Don't know the specs of that "VP cam", but generally speaking, a cam is suppose to improve the breathing of the engine. With that, you should expect the "Boost" to drop some.
- Remember, "Boost" is nothing more than an indicator of the resistance to the flow of the charge-air through the engine.

Have you notably changed the IPs static timing (intentionally or otherwise)? That'll affect power as well as the apparent boost figure.
 
the only timing that I have done is move the ve pump over closer to the block. The pump is turned up. It's everything that my buddy usually does to a first gen.

I do know that the vp cam does have more lift out of all the 6bt motors.
 
Only on the exhaust side. Iirc the non ic ve cam had the best numbers overall but I can't find the specs.

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Apmaw55 said:
the only timing that I have done is move the ve pump over closer to the block.
Click to expand...

- Remember, our turbo(s) are driven by the heat of the exhaust gases. Advancing the static injection event timing (shoving the IP toward the engine head) will have more heat of combustion converted to crankshaft power (ideally), and less to power the turbo(s).

Have you considered adding one of the M&H dynamic timing spacers? It'll give back some low engine RPM torque while still allowing more advanced timing so as to better use the fuel afforded by the larger injectors.
 
assuming based on sig you have an airdog installed, whats the pressure ? . i would check all fuel lines and filters for restriction/leaks . check for boost leaks , clamp the wastgate line shut and see what itll do. check boost ref to afc make sure theres no leaks.

what else broke when you lost the cam? bent pushrods , did it require head work?

if you want to ppump it its pretty straight forward , if your trucks a 91 you have small bowl pistons (unless you swapped them in the rebuild) and your 91 head has the 7mm injector bores. just need different injectors , the body is different so are pop pressures.
 
Air dog is set to 13lbs and I have looked for leaks but can't find. As far as the waste gate I wanna say it as welded shut but don't quote me on that. I will look real good tonight.

When the cam broke it bent push rods and broke cam and even turned the cam gear a lil. Broke a few tappets. So what I did was rebuilt the hole thing. Didn't have a hole bunch of cash at the time like I do now. So I went to a friend of mine at all out diesel and he hooked me up with a vp cam same length push rods and tappets for a vp motor. I took the head to the machine shop and they put the 60lb springs and resurface the head. They reseated the valves and I put all new main bearing and seals. Kept the 91 1/2 Pistons in No scaring or anything on the cylinder walls.
 
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