All about rpm's and air flowMay 9 2012 at 6:05 PM
|Jack (Login 427highriser)|
Response to 390 build , 69 mustang (help)
With a 390, you will have to spin it to reach your horsepower goals. Whether it is 6500 or 7000 or somewhere in between. That means a blueprinted, balanced shortblock with ARP rod bolts. To spin it, a bigger camshaft is needed. 294s Comp Cams will do the job (it will want 10:1 static compression)
Up top, it's all about air flow. If you are going to spend any cash on the motor, spend it on the heads. Keep the iron heads, install bigger valves, and spend some money on some porting. Port match the intake (jay browns book proves the horsepower gains) and back-cut the valves. 750 will work, but an 850 may increase the power as you get higher in the rpm's.
With rpm's comes oil deprivation and requires stiff springs and tough pushrods
- porting - bryan on May 9, 2012, 9:26 PM