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View Full Version : 5068 truth or myth,.



phantom309
05-26-2011, 20:34
Well my dahooley wannabe puked last fall,. 1 hole dead,. i pulled it today,. it,s a nice hole dead centre on the piston with a nice smiley crack right across,.
Now to be honest i caused the problem,. i put a bastid chip in it that came out of a guys tool box drawer,. and it made tons of power,.the head off the other side has cracks between the valves on two holes,.
I checked the pump number and i have the 5068 pump,. 94 HD specific,.
some say it pumps waay more fuel,. some say it is no difference,.
anyone here know for sure? I modified the GM* turbo housing a little and welded the wastegate closed,.It could boost up over 22psi,..so it was definitely getting fuel,.i did dyno the truck once,.at a dodge cummins dyno day,. but when i posted the results i was run out of town on another forum,accused of lying etc,. and it all went bad,.
So,. 5068 pumps truth or myth??

thanks eh?



Nick
oh,.. yes,.. yes,. i know,. you get what's coming to you if you pump up a 6.5,. but i have 3 running motors for spares,and it's fun,.

john8662
05-29-2011, 00:40
Supposed to be a different cam ring in there, the rest of the parts are the same as the rest of the pumps.

Your IAT's and EGT's with a GMX turbo and no intercooler were probably very high even for anyones performance tune (thinking that may be why you holed a piston and had cracks everywhere).

I'm with you though, I'd like to think the 5068 does more fuel. Dunno. I've got one for parts that I wanted to mix and match parts into a 5288 or so (have tons of those is why...) that it'd work with my '95's programming.

Next time to turn if up consider an intercooler and a HX Holset turbo for more air, some 18:1 pistons would certainly help it live too.

What was your dyno results?

jggiedeman
05-31-2011, 12:27
I just purchased a '94 K3500 Duelie. The IP was changed under warranty Dec '05 to a 5942. I don't know about some wiring issues but would you chack if you have the following. The wiring harness connected to the optical sensor - I have an electrical "noise" filter that has three wires cut and taped to the filter. the only wires undistrubed are the yellow and two white ones. The three other wires are connected to another harness leading directly back to the PCM. My wires do not match factory colors bu they are dark blue, dark red and dark green. The wires do terminate into the PCM where they are supposed to but I don't know if this was a dealership mod to get the PCM to accept a 5942 pump. Thanks for any help,
Jerry

phantom309
05-31-2011, 18:50
Supposed to be a different cam ring in there, the rest of the parts are the same as the rest of the pumps.

Your IAT's and EGT's with a GMX turbo and no intercooler were probably very high even for anyones performance tune (thinking that may be why you holed a piston and had cracks everywhere).

I'm with you though, I'd like to think the 5068 does more fuel. Dunno. I've got one for parts that I wanted to mix and match parts into a 5288 or so (have tons of those is why...) that it'd work with my '95's programming.

Next time to turn if up consider an intercooler and a HX Holset turbo for more air, some 18:1 pistons would certainly help it live too.

What was your dyno results?

246rwhp, 658rwt,.


i want to buy one of the "A" team turbo,s,.
My other 94 6.5 has 3:42 gears,. and it makes a huge difference in egt's with the rpm back,. the 4:10's in the dually are a waste of fuel and the gm8 is a restriction as we all now,.i just bought another set of 3:42's for when i get a heart sorted out,.i,m going to fab a larger oil pan for it,.

phantom309
06-02-2011, 18:49
http://i39.photobucket.com/albums/e157/wtfuashols123/MVC-015S-1.jpg?t=1307065574
pic of the head from the opposite side of the motor (all pistons were still good this side,.)

http://i39.photobucket.com/albums/e157/wtfuashols123/MVC-014S-2.jpg?t=1307065252



Nick

Edahall
06-02-2011, 21:15
The heads on my 1982 Suburban are cracked between every single valve just like that. I JB welded some copper tubing to prevent the cracks from leaking. It's been nearly 10 years and I haven't had any problems.

Altec
06-02-2011, 22:16
First post here. :) Admittedly been hunting this forum for all the hidden goodies of information...

I don't know much about the DS pumps, but I will put my ear to the ground, and report back if I find anything on paper.

Those dyno numbers are nice, but I can't see why anyone would call you a liar... Your results just show what low RPM boost does to a long stroke V8. :D Better then all the 260-ish HP pulls I see with a 1.8x torque number. With a cooler charge, and a better spool you have no where to go but up! And it'll live longer too! :)

You give me hope for my 6.5NA I'm working on.

john8662
06-03-2011, 09:50
246rwhp, 658rwt,.

I'd buy the HP, sweet runner to be that, I believe you on this one. The TQ not so much.

I also agree with you on the gears. I've pulled with 4.10's and 3.42's and when it comes down to it I can't really say I had any troubles with the 3.42's.

I'm swapping to 3.73's on my Dually, but it's a 4x4 and running 235/85 R16's. so the Tall tires put me where I wanna be.

phantom309
06-03-2011, 19:36
I'd buy the HP, sweet runner to be that, I believe you on this one. The TQ not so much.

I also agree with you on the gears. I've pulled with 4.10's and 3.42's and when it comes down to it I can't really say I had any troubles with the 3.42's.

I'm swapping to 3.73's on my Dually, but it's a 4x4 and running 235/85 R16's. so the Tall tires put me where I wanna be.

mebbe i can't remember the torque correctly?? 658? 568? 865?
Kinda like all my stuff, the older i get the faster it was??

i had a manual switch to lock the converter,.and just as it shifted into second gear the guy locked the converter then flattened the throttle,.

Altec eh??

Nick
truck ran 17.27 @ 78.6mph w 2.47 60ft. 6786lbs 2wd.
http://www.youtube.com/user/phantom309ish#p/u/3/pd4wbZ-eSus