Common rail conversion using duramax parts

Morgan@Midwest Diesel & Auto · Sep 16, 2014

http://powerstrokearmy.com/forums/showthread.php?t=32772

Twisted addiction is the guys screen name. He may still have it.

NyCowboy87 · Sep 16, 2014

Straight from ppl rule book, it's rather gray but I've already had one tech official say no to a p pumped 7.3 in 2.6.

Sent from my iPhone using Tapatalk

Morgan@Midwest Diesel & Auto · Sep 16, 2014

There is no reason you can't run a p-pump according to the rules. I does not state any where "no p-pump on a non factory p-pump equipped engine". There has been others run a p-pump in 2.6...

Hotrodtractor · Sep 16, 2014

Morgan@Midwest Diesel & Auto said:
There is no reason you can't run a p-pump according to the rules. I does not state any where "no p-pump on a non factory p-pump equipped engine". There has been others run a p-pump in 2.6...

Agreed 100%. Nothing in those rules precludes p-pump conversions of any flavor.

NyCowboy87 · Sep 16, 2014

I agree with you both, but like I said earlier I've already been told no. So what's the next step? Do I build it then protest the rule if and when they say no?

Sent from my iPhone using Tapatalk

Hotrodtractor · Sep 16, 2014

NyCowboy87 said:
I agree with you both, but like I said earlier I've already been told no. So what's the next step? Do I build it then protest the rule if and when they say no?

Sent from my iPhone using Tapatalk

Call Johnathan Mears 502-817-7494. He is the Tech director for PPL.

When we had this discussion here in the COTPC - we determined that we would let it run if someone built it. The rule does not in any way prohibit the construction of such a setup for that particular class. Our wording is identical.

Morgan@Midwest Diesel & Auto · Sep 16, 2014

I wouldn't be afraid. They can't change the rules that are already written. Heel there was a duramax truck with a belt driven p-pump on the passenger side of its cummins at scheids this year. If it's legal fuel system for a cummins then it's legal for all makes.

NyCowboy87 · Sep 16, 2014

Hotrodtractor said:
Call Johnathan Mears 502-817-7494. He is the Tech director for PPL.

When we had this discussion here in the COTPC - we determined that we would let it run if someone built it. The rule does not in any way prohibit the construction of such a setup for that particular class. Our wording is identical.

Thanks Jason, just talked to him and p pump is a go for a 7.3. He said they changed it for this year.

Sent from my iPhone using Tapatalk

Magnum PD · Sep 16, 2014

Get to work then!

PsdPullerJr · Sep 17, 2014

How much air can the 7.3 heads flow? Is it worthwhile to p pump one without running twins or an unlimited single?

NyCowboy87 · Sep 17, 2014

My understanding is that a good ported 7.3 head flows about the same as a ported 12v cummins head.

Sent from my iPhone using Tapatalk

Stroked777 · Sep 17, 2014

I'll have to make it out west to see this thing run. I'm near Albany so it isn't that far of a drive for me down i90

smokinstroker92 · Sep 17, 2014

Yes the 7.3 heads can actually be made flow very well. Over 200cfms at 0.500 valve lift very close to the flow of 12v heads. If I where building a 2.6 truck I would machine the plenum runners from the head and fabricate runner intakes that direct straight to the ports this would help the flow a great deal more. The main restriction on the intake ports is the #2&7 I believe where the casting makes the port very long and narrow the other ports could be ported more but it is best to be flow matched.

NyCowboy87 · Sep 17, 2014

I have a set of heads that have the plenum milled off and some extensive port work done...

Sent from my iPhone using Tapatalk

Morgan@Midwest Diesel & Auto · Sep 17, 2014

smokinstroker92 said:
Yes the 7.3 heads can actually be made flow very well. Over 200cfms at 0.500 valve lift very close to the flow of 12v heads. If I where building a 2.6 truck I would machine the plenum runners from the head and fabricate runner intakes that direct straight to the ports this would help the flow a great deal more. The main restriction on the intake ports is the #2&7 I believe where the casting makes the port very long and narrow the other ports could be ported more but it is best to be flow matched.

We did a 12v head here that flows right at 300cfm at 600ish lift.....

200 cfm is no better than a 6.4 head and it is feeding a lot less cubes.. remember on a turbo limited, fuel only class, feeding big displacement is not an advantage...

Been proven time and time again in 2.6 that big displacement cummins and stroker duramax's do not make hardly anymore power than their smaller displacement original versions. Without larger turbos and more air, your just wasting efficiency and money.

A big bore de-stroked 7.3 with 300 cfm heads @ about 6.0-6.5 liters displacement would be an animal. But then your right back at just using a 6.4 to begin with being cheaper and easier.

The whole "no-replacement for displacement" is a foolish thing to say when your running a turbo. Especially in an inducer limited fuel only class. It's all about efficiency of the engine for the size/flow of the turbo your allowed to run.

Morgan@Midwest Diesel & Auto · Sep 17, 2014

Don't get me wrong, a de-stroked 7.3 with super ported heads and a p-pump would be bada**. But it's not gonna be cheap at all.

superpsd · Sep 17, 2014

It would be nice to have a common rail 7.3 but a built 6.4 or 6.7 would likely be heckuva lot easier and cheaper.

Morgan@Midwest Diesel & Auto · Sep 17, 2014

6.7 is a long ways off for high hp/rpm competition use.

PsdPullerJr · Sep 17, 2014

What about sleeving and running a smaller piston? I've thought about that for a few years now. Would take the displacement out and I thought longer rods helped on the torque side of things. As you said, I've felt for several years that the 7.3 was at a disadvantage having the bigger cubes. After seeing what you've done with a 6.4 and with swamps putting one in 99-03 chassis, that's gonna be my new play engine. After this year I'm done wasting money on something that can't compete in work stock. It's making me wonder about a p pumped 7.3 or a 6.4, which would be the best bang for the buck.

Morgan@Midwest Diesel & Auto · Sep 17, 2014

Best bang for the buck is a commonrail 6.4.

By putting a smaller bore in a 7.3 you would be doing the opposite of what you should be. You want larger bore Dia. Stroke is not gonna help the high rpm/hp that is needed for competition use in fact stroke is kind of the enemy. Destroking a crank would be much cheaper than sleeving 8 cylinders. Just need a longer rod for less stroke.