Any of you perf guys tried an aftermarket cam? I was wondereing what the difference in power, power curve, idle, streetability would be...
Mark.

 

Anyone? Nobody has put a performance cam in their 12 valver out there??
I'll settle for second had stories and rumors!

 

Cams rule man.
Get one you wont be disappointed.

 

How did it change your powerband? Did it kill the bottom end? Does your engine "lope" at idle?

 

Increased throttle response, lower WOT egt's. More airflow and power overall.
Lowers boost levels through more efficient engine breathing.

No loping. Loping usually comes from fuel delivery mods.

 

will the cam go wumpsh....wumpsh...wumpsh like on a gas

 

I dug around in my notes and found this for what ever it is worth> Lobe centers are tight to remove old exhaust gass from the chamber by design. The intake and the exhaust are open at the same time during overlap to blow a fresh charge of air out the exhaust valve to help clean yukkies. The problem is when we increase boost with more TIP turbine inlet pressure the exhaust goes higher that the intake in most cases. In the old 12 and 24 valve the highest TQ numbers was gained with overlap clean out being at optimum rpm range. This is done with turbine housing size, cam timing points, and fuel levels. Some people get hung up in boost numbers and never remember the other side TIP, it can kill your engines performance by leaving the yukkies in the chamber for the next stroke and contaminated.
Remember the same does does not hold true for diesels. The dont ingest fuel/air mixture. So the lopey idle is not going to happen with a cam. The fuel is shoot into the chamber way after intake valve is closed.
I was also told that 2 generation camshafts wont work in a first generation as they have different lift/ duration/ overlap. This could have changed but from what I have read max power will not change with the addition of a cam, lower rpms power will. Driveabitity and egt are much better/improved. Along with better spool up, less smoke. A fellow asked why did my boost fall off after the camshaft change. The answer was more overlap. Some have reported 75-100 deg drop in egt. On the nwbombers a fellow wrote that the egt reduction was caused by overlap.
Anougher fellow wrote> camshafts control air, not fuel. You change things like spool time, boost, smoke, egts. Pulling a bigger turbo on is like pulling in a cam in a gasser. It can move the power curve up and down the rpm band.
I hope that I got some of this correct and it at least helped answer a little of the post about loping. My 95 use to idle different but it was because of timing. I would thing that big injectors might also. Any of this correct Jim

 

Pretty much all of that is correct. I've cammed both trucks and both trucks had a broader powerband and ran less boost with cooler EGTs.

brandon.

 

Thanks, I had hoped that was correct, you know a lot more about the Dodges than me Jim

 

Feel free to correct me, but on 12vers at least, the whomp, whomp sound made by most pulling trucks it due to the substantial increase in timming. Isn't it rumored that Schied and other fellows are running timming upwards of 45 degrees? The lower compression ratios they run probably have something to do with that as well.

 

Most are closer to 50* or more

Chris

 

And I thought joefarmer's 32* was nuts!