Which is????

 

2000 RPM for 20 minutes is what Dockboy told me today. I've heard everything from that to varying RPM between 1500-2000 for 15-20 minutes.

No physical progress today, but I got a wealth of info. Spent a couple hours on the phone with Dockboy and got all the wiring for the plugs and OBDII port straightened out. Kai sent me the diagrams, but I needed a little guiadance on what's what. Greg got me all the info I needed I do believe.

I also had a few questions on the PCS harness. There are some loose, unterminated wires that I couldn't figure out where they went. After a chat with one of the tech guys at PCS though, and it all makes sense to me now. Just need to identify a few more specific wires...I started a new thread for that.

Greg also filled me in on a few more miscelaneous things.
1) The ECM has a security setting in it that won't let the truck start once it's been separated from the chassis. A Smarty programmer/downloader can correct this though. I'm going to see if I can find one to borrow for this, but if not I'll have to go ahead an buy one. That's something that I hadn't planned on getting for a while.
2) The upper radiator support holes where the radiator mounts have to be elongated a little bit to allow the top of the radiator to tilt about 1/4" forward. The Cummins engine sits at a little different angle, but moving the radiator will straighten it out.
3) The Cummins is a lot more front heavy than the 7.3, so it won't just sit on the crossmember without the trans bolted up. I'll have to use the engine hoist to hold the front of the engine up while I bolt the trans up.
4) To get the engine to clear the upper cowl while putting it in the chassis, it actually has to be tilted forward to get the oil pan to clear the crossmember. Once the oil pan has cleared, the engine can then be lowered into place.

I'll say that while this is challenging, the advice I'm getting from guys who have done this before and help from the forums is invaluable. I couldn't imagine trying to do this without any guidance.

 

I have never heard of having to "break in" a cam. 'Course, it has been a while since I put one in so maybe it is something that has to be done with today's cams. Enlighten me, Jeremy.

 

well what ive always heard is that you HAVE to break in a cam... like he said about 20 min on 2k rpm i forgot the real reason for it tho

 

Mark, it's more of a concern with this being a flat tappet cam. The cam lobes have to be worn in on the lifte surfaces before the engine is run normally. It's pretty much a non issue with a roller cam & lifters, which are much more common place now.

 

How much heavier is your cummins then a 7.3? Is it enough that you have to beef up your suspension?

 

5.9 is maybe 100 lbs heavier

 

That actually surprises me greatly. I would have thought the 7.3 was heavier. . . by a large margin too.
Timmy

 

I would have thought so too, but with 100 lbs that shouldnt make much of a difference.

 

I want to say that a fully dressed 7.3 is about 1200 pounds and a fully dressed 5.9 is about 1500 pounds, so a 300 pound difference. I honestly don't know for sure though, that's just what I remember hearing. Shouldn't be much of a difference though and I don't imagine it will change much about the truck.

Tim, what you've got to remember is that the 5.9 is built a lot stronger than the 7.3. Rods are heavier, cam is heavier, crank is heavier, and the block may even weigh more. Everything in that Cummins has more beef to it than what IH put in the 'stroke. If a 7.3 were built with the strength that the Cummins is, it would probably weight 1800-2000 pounds.

 

That explain why they take so much abuse then huh?
Timmy

 

Exactly!

 

I do remember that you had to use the special grease that came with the cam to prevent the lobs from galling when first starting. Maybe, at that time, I was of the impression that real men didn't read directions........

 

No special grease with this cam, but I used some assembly lube with moly and graphite in it. Knowing what I know about those two substances, I'm pretty sure galling won't be a problem. Or at least I hope it's not.

 

Jeremy, i,m really impressed on how everything is coming together. The end result is going to be sweet to say the least.