12 VALVE CAM IN 24 VALVE
 

Has anyone tryed a 12 valve cam in a 24 valve engine? I have a 98.5 24 valve and a cam from a 96 12 valve and am wondering if I would get any milege and/or performance gains.
Any info on this would be helpfull!

if you wanna sell the cam let me know

The flow on the 24v had is far superior to that of the 12v. I can't imagine there would be any benefits gained bykilling off half the valves.

How is it gonna kill half the valves? They have the same # of cam lobes! Not changing the head here.

yes it works, yes I have done this, yes it will give you some gains.

if you would like, I can give you my friends phone # who is using one in his engine now.

just send me a pm

I also have OEM high horse cams on these cam, the intake lobe is 1.867. (on original camshaft , they are 1.857)

the high horse power ones holds the intake open more and about a split second longer than original

Could you explain how the 12v cam is better than the 24v cam? Looking at a spec chart they both have the same amount of lift on the intake and 24v cam has more lift on the exhaust.

Not trying to sound like an :moon:, but how does the overall height (1.867) have anything to do with the lift? If it is a regrind or just ground that way it will be smaller than a stock cam. My stock 24v cam was 1.8something and the helix 2 (marine) cam was 1.7something, but had more lift.

1.867 is the top point (where you intake valve is open all the way, this is the high horsepower cam from Cummins, for the 12 valve

the specs from Cummins factory on a 5.9l 98.5 to 2008 are
intake 1.857" (47.173 MM)
exhaust 1.796" (45.636 MM)
these #'s are from the book

the high end HP cam, intake is 1.867, this allowing more fresh air to enter the chamber.

there are company's who make there cams with more lift or less lift on the lobe, depending on what application you are wanting, some will argue to the fact that there cam that they have ground is showing more performance than others.

when it comes to high performance, the .000 numbers make a big difference as you stated yes your cam is 1.8 something but that one thousandths can make a huge difference (your cam is stock at 1.857, the 12v is 1.867, meaning .01 difference

we are going to have a 6bt 5.9l engine ready to be on a dyno,sometime in the summer, I will share all info on the difference set ups.

I am by know means trying to start anything, I got screwed on my last build because a certain local "shop" told me what I needed and that is what I bought. This go round I am trying to learn all I can, before buying anything.

Here is a spec sheet off of Colt Cam's site.
Attachment 48836

The 1.867 is the overall height, not the lift. I took a set of calipers and measured the stock cam out of my 95 12v engine and the intake was 1.881 and the exhaust was 1.855. In the "Original Cam" picture the overall height is 1.00, the lift is 0.400, in the "Reground Cam" picture the overall height is .960 with a lift of 0.400. They both have the same lift, but the overall height is smaller on the regrind. What is the lift on the high horsepower cam?
Attachment 48837

no big deal. as soon as I get back to the office I will post some documents that I have on camshaft grounding, lift,etc.

a stock 12v cam in a 24v is a step backwards it would only hurt you