It's pretty similar to a VP, slightly different model. Like a VP33 or something like that. Don't see enough of them to know much about the VP styled pumps.

 

First post , lurked off and on for a while now. Have a few questions if someone can help and resurrecting this old thread:

The 5.9's had issues. Some with weak head gaskets, then there was the dowel pin.. I know my father had his issues with each of his 3 Dodge trucks, every one was modified to some extent. And he bought this RV so my mom and him could travel even after he couldn't drive. Had to be a Cummins. Wouldn't even look at anything else. Now I'm keeping it on the road and doing the stuff he would've if he was still around. So...

Does the 6CTA 8.3L have weaker head gaskets, comparable or even stronger than the 5.9 did? Has there ever been issues with the dowel pin or other problems I should be aware of?

With the Cummins 6CTA 8.3L circa 1994 in a 30K lb "truck" what is considered safe when messing with the P7100 pump timing? 14, 15, 18? How far can one go before you see "issues"?

I'm attempting to get a feel for what would be a conservative bump and what is considered running too aggressive. It can be a fine line sometimes. After all, this is for a retired, widowed, great grandmother's coach (my mother) and I need to keep her rv running reliably so she can terrorize our Nations' highways one ricer at a time... The straight pipe at least keeps them off her back left corner, merging towards the hammer lane is a lot easier now.

 

a isc 300 8.3 in 2001 had a vp type pump not sure when the p pump was on them but i know my 2001 isc dont have a p pump also in 2001 the isc 300 8.3 made 300 hp at 2,000 rpms

 

I'd assume the ISC 8.3 is a different motor with all the electronics on it. Like pre-97 12V 5.9's vs the 24V electronic 5.9's from 97.5 and up. May even be more differences than that.

We wound up bumping timing up to a conservative 14.25 on our 12V 8.3L 6CTA, haven't moved the plate yet but EGT's are sub 1K and boost is at 21 psi. Waiting for the heat of summer and we might bump it enough to run mid 20's on boost for better holding power on smaller hills with the cruise on. Right now it still drops 5 mph. Before that we'll get a baseline on mileage. Needs a water pump next, JUST started seeping a little.