Ok, I am giving some serious thought to this modification on my truck mainly for the reliability. My truck is very mild and near stock, but I plan on having this truck till I die so I don't mind the money this mod costs because I look at it as a trade off for reliability down the road. The questions I have are these:

1. After the P pump conversion, would there ever be a need for any programmers or boxes on this truck? If so what parameters would they control other than adjusting the speedometer for changes in tire size...etc.?

2. I would like to tackle this myself, but am finding little information as far as a tutorial or a guide, anyone know of any good resources that might help me?

3. After the initial install, I am worried about being able to correctly time the pump if need be. Do they all have to be tweaked or do you ever happen to get lucky and everything work? Is this something the average weekend mechanic can tackle or is this a job for a diesel mechanic with specific tools for this?

Any help would be appreciated, its always nice to be able to get answers from those who have done this kind thing before. Thanks in advance!

 

1) Speedo is the only reason. Dealer or a friend with a DRB-III tool can adjust it. Cost me $50 for the dealer to correct it.

2) Go to Comp-D, has a dedicated section to P-pump 24v conversions. Sign up, search and read a lot. Most of it has been hashed through on there. I found my info on here 5.5 years ago, but it was few and far between. Biggest thing you need to know is how to find proper TDC and setting the timing, which is all related to 12v.

3) I think anyone with a decent mechanical ability and common sense can pull it off. Timing kit is about the only special tools you'll need.


Best thing to do, in my opinion, is to buy a complete 12v (preferably one thats broken so its cheap) and rob it for parts. Will be much cheaper than the kits sold by shops. If its a running engine, you can sell the remainder of the parts to make your money back. There are some guys who made money by doing the conversion. I would recommend a cam at the same time. Perfect time to do it, and you can run a 12v lift pump instead of an electric one to make everything much simpler. By this time, its time to consider just swapping in a 12v and selling a running 24v. Breaking even should be pretty easy.

 

Probably the only issue would be to keep the cam gear from the 24V engine and adjust the 12V gearbox housing so your tach would work.

Being a manual truck, its a real easy swap. I would keep the motor mounts from the VP engine for the 12V myself. Seen a few 12V motor mounts that been broken over the years. The 24V motor mounts seem to hold up better.

The 24V VP head (stock) flows about 20cfm more than a stock 12V head. 12V heads seem to take egt's better without crackin. I've done a few 12V head with large valves and max ported over the years, with decent flow numbers rangin from 240 to 260 cfm at 0.500 lift. The china 12V heads have more meat in the right areas for head crack prevention.

 

Ok, a few other questions....

Everyone says the check engine light will remain on, is there a way to get the ECM flashed to turn the check engine light off? Also, will my cruise control work ok after this conversion? Another thing is what size lines would I need? I am guessing either the .078 or .084, but any other advice would be appreciated!

 

Pull the bulb. Easiest way. The codes will mean nothing from here on out, unless its auto tranny related. Either line would be fine. Not much benefit to the larger lines until you get into bigger pumps. Ron Allen runs .084" lines on his 1200 hp 24v.