Cam Specs

I know its not a rod but we can not find cam specs anywhere for my freinds truck.

1987-GMC-K3500Dually

454-(7.4L}-TBI Stock

please we have tried everywhere,so if anybody knows please help us out

 

bttt

 

bttt

 

I don't have them but out of curiousity, why would he want to know?

Frank

 

Cannot confirm these numbers anymore, but I have the following listing for the application you have:

Adv. Dur.:280*/292*
.050" Dur.:193*/204*
Cam (lobe) Lift:.234"/.253"
Valve Lift:.398"/.430"
L/S:120*
ICL:108*

Thanks, Gary in N.Y.

P.S. The above numbers are from "Camshaft Machine Co." which did most G.M. cam work. If you're looking to replace the OEM cam just pick an "RV" style piece, this will place you "in the ballpark"!

 

I could be mistaken but I believe it has the same hydraulic cam used in most low-hp Mk. IV BBC applications, including light trucks:

.398/.398 lift; 196/196 duration @ .050; 113 LC

Even the TBI peanut-port engines like more lift than that. If he needs to change cams, I'd look at the Comp Dual Energy 255DEH (part 11-206-3). It seems to work fine with the stock computer, in my experience.

Edit: I believe that the cam numbers that Gary lists are for the older version, 3874872; the newer version is the one I listed. Both are considered correct & interchangeable. In practice, the few I've measured have been all over the place anyway.

 

thanks guys,hamb to the rescue again,,,,,greatly appret

 

this being used a tow vehicle