Don Terrill’s Speed-Talk

Very little or no difference on 800-900 HP, SB Chevy engines= The ported ones usually LOOSE a lot of torque, but do gain a few HP, way up high in the RPM range. Not a good trade off





JOE SHERMAN RACING

Many would just change the pump shooters to compensate, and levee the main jets alone




JOE SHERMAN RACING

It is pretty common to not get much if any HP increase when you put a vac pump on a good stock type short block. I have dyno tested many of these pumps over the years, and 15 or 20 horsepower is a very common gain. On a specially built drag race engine, when I removed the pump, it lost over 50 horse...

I am a SCAT dealer, but if you are not local to so Cal-- the freight can get expensive




JOE SHERMAN RACING

Just use the regular gasket ( 4.080 ) NO PROBLEM



JOE SHERMAN RACING

I am 77 years old- What is your excuse ?


JOE SHERMAN RACING

I missed that ! -6 would be pretty safe-- I use -5 all the time in the street racer stuff I build-- It will not make any difference on the dyno- Hotter seem to last longer-- Look at the ground strap after a dyno pull



JOE SHERMAN RACING

The compression ratio is what tells you the plug heat range requirement- What is it ?




JOE SHERMAN RACING

If you ever saw how they make production headers, you would understand how this can happen. When header are built in a jig, they can vary quite a bit. Their idea of clos tolerance is plus or minus 1/8 inch





JOE SHERMAN RACING

To the O P -- I( was running a 288-304 on a 108 Cl- With the 3.75 stroke, the HP peak was at 8000 RPM- I use 1.8 intake rockers, but 1.60 exhaust rockers-- 875 intake, 710 ex lift- Rev engine to 8800 every pass



JOE SHERMAN RACING

I do NOT agree that his cam is too big-- I run much bigger cams than that, and I make much more horsepower at a higher peaking RPM




JOE SHERMAN RACING

Do you still have the roller cam and lifters ?



JOE SHERMAN RACING

Pretty similar to what I would use



JOE SHERMAN RACING

I have done such an engine several times--- no big deal for me-- pretty expensive though




JOE SHERMAN RACING

The AFR 220 do not need shaft rockers, but ,the 235 heads will require them-The 235 with shaft rockers will be considerably better, but cost a lot more If you get shafts, use 1.70 on the intakes only--forget the NOS



JHOE SHERMAN RACING