Superduty ,the information hopefully below maybe helpfull to your
understanding. The "cut" references eg "AA", "A" "B" etc refer to the
the size/cut/angle of the exit side of the Impeller respective to the
exit side large and small diameters . That "cut" determines/controls
how and what water is "moved" of course depending on the actual
horsepower applied and absorbed. We reserve Smaller (alphabetically)
Impellers (b's and c's) for Smaller displacement engines as well
engines built to make power at higher rpms . Engines that make Big
Grunt power/torque at lower rpms can swing a large Impeller such as a
9.5 inch or AA and move the same water without turning the rpms
re the headers if they are in decent condtion theres place in the
Valley and in AZ that will "hpc coat" them for around $200,lines run $150
rechrome is a different subject and not worth it IMO , a new set of
Chrome water injected headers runs $895 complete Good Luck Tom
IMPELLER SPECIFICATIONS
IMPELLER SIZE LARGE DIAMETER SMALL DIAMETER MACHINED ANGLE
9 1/2" 9-1/2" 8-1/4" 25 DEGREES
9 1/4" 9-1/4" 8-1/4" 20 DEGREES
AA 9-3/32" 7-13/16" 25 DEGREES
A 9" 7-1/4" 30 DEGREES
B 8-3/4" 6-3/4" 33-1/2 DEGREES
C 8-1/2" 6-1/2" 33-1/2 DEGREES
H.P. 9.5 9.25 AA A B C
150 2900 3050 3200 3600 3800 4050
200 3200 3350 3500 4000 4200 4450
250 3450 3600 3700 4300 4500 4800
300 3800 3950 4050 4550 4800 5100
350 4050 4200 4300 4750 5100 5350
400 4250 4400 4500 5050 5300 5600
450 4450 4600 4700 5250 5500 5850
500 4650 4800 4950 5400 5700 6050
550 4800 4950 5100 5550 5850 N/A
*THESE RPM VALUES MAY VARY ACCORDING TO HOW YOUR BOAT ALLOWS THE PUMP TO LOAD
HORSE POWER REQUIREMENTS ARE AT THE PUMP SHAFT
