View attachment 1715907144
Take a good look at this;
The lines cross at 5250rpm so the numbers on the left axis can be used for both torque and power. Consider the blue line; the cam may be stock because the power is peaking at the correct rpm for a stocker. But notice that the power is about 300hp. Therefore; I wonder if this engine is otherwise stock.
Now consider the red line;
>see what happens below 3000? You can clearly see the trend pointing to a loss of torque and power.
>See the power increase by 3000? Is that 4hp?
>the Power hit comes at 5000rpm. Is your engine up to it.
>What gears are you running? and What stall?
Look carefully.
This red cam wants a stall of 3500 or more, to stay on the pipe at the 1-2 shift (59% with a 904/727) with a 5300rpm shift, otherwise the rpm will drop from 5300 to .59 x 5300= 3130. Look on the graph. What is the power difference at 3130?
What is your speed in Second gear at 3130?
With 3.23s, I get ~48mph. Therefore, on the 1-2 shift, at 48 mph with any stall less than 3130 the red cam offers little to no more power than does the blue line.
Now lets look at that 3000 rpm in First gear. This is about 27 mph . So below 27 mph, the blue line will have more power.
Your gain thus, with 3.23s, and a sub 3000 stall, from the red over blue, is,
beginning at say 4hp@27mph and extending to 50hp@48mph, then on the 1-2 shift, the power drops right back to ~4hp@48mph. If you spin the tires and short shift, you are sure to be disappointed.
This cam wants a 4 speed; or a stall over 3500, AND throw the 3.23s away.
Since you have to spring for a hi-stall and gears anyway, you might as well do that first and leave the factory cam in it.(assuming it is good). Both the 4-gear and or the hi-stall will shorten up your powerband and increase your AVERAGE power over the full range, thus you may be pleasantly surprised by the blue line.
As for the blue-line, it peaks at around 4500, but the line is so broad and so flat that you can easily run it to 5300, or more. From 5300 the rpm drop at 59% is to 3130 again, but a 3500TC would put the incoming power close to the outgoing power and so that is as good as it gets.
Run the blue with 3.91s, compared to the red with 3.23s, the blue-line will put more torque down to the pavement at almost any rpm. For instance, the red line would be putting down, at 5000rpm, say 360 ftlbs x2.45 x3.23= say 2860 ftlbs into the rear axles. Whereas the blue line, also at 5000 looks like 310ftlbs x 2.45 x 3.91=2970ftlbs.
Hmmmmmmmmmmmmmmmmmm
