heads to a cam in a stock tbi motor is almost a toss up. but just for kicks go check the specs for a stock tbi flat tappet cam.
yes the heads suck for upper rpm flow in stock trim.
but everyone needs to remeber big heavy 4x4 needs low end tourqe to get rollin more than upper rpm hp.
so the lower flowing heads in a stock tbi give good bottom - mid range power to get the 4x4 heavy hog rollin.
Not arguing, but here is a thought I had when I read this.
It has always been a given, that trucks with big tires, heavy bodies and frames need low end torque.
And for highway travel that is true unless you are running insane numbers in the axles.
But, consider this. With axle numbers in the 5s, what is your RPM range now?
To take it to an absurd point to illustrate what I mean, consider a truck with 3.50 rear end, standard tranny without a granny low gear, running 38 inch tires.
When you release that clutch, that engine is going to have to start making gobs of torque, and its going to have to do it from idle up to around 2500-3000 RPM.
Then, you shift, and it starts over again.
But, you put a set of, say, 5.35 gears in there, and suddenly your need for torque has shifted to a higher RPM range.
At a 1000, you are not accelerating those tires very fast, which is what you need the torque for.
That engine is going to ramp up a lot faster than before, and will need a different power curve.
Then, when you get offroad, consider the difference between a single 205 in low range, and a doubler with both in low range.
To get the same tire speed, there is going to be a huge difference in engine RPMs.
You are still going to need low end torque, but with some of the gearing you are doing these days, I suspect that some of your power curve needs are going to be closer to that of a street racer than you would suspect..
Just something to consider.
The factory police TBI engine had a roller cam if that helps prove my point!
