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Jeff Chambers · 11-18-2002, 01:09 PM

What I was getting at was that I don't believe the 351 cam that he's running was designed for 1.5:1 rockers. I could be wrong, but its suspicious to me. Therefore, it might not really be giving the lift that you've calculated. The only real way to know is to do a vavle lift check at the retainer, and even then you'll have some valve train deflection that will decrease the effective lift. If he's not getting the lift that he thinks he's getting, then it might be impacting the rest of his combination. The engine won't make the power or sping the RPMs if he's shorting himself on valve lift; it directly affects the volumetric efficiency.

Gears won't effectively change the powerband. You use gears to get you to the powerband that your engine is delivering. They do however provide torque multiplication. So a 4.10 gear is going to give you better leverage than a 3.55 gear. Lower numerical gears will allow you to run more MPH at a given RPM, while higher numerically gears will allow you to run more RPM at a given MPH.

The specs on my cam are different than his....I'll leave it at that.

11-18-2002, 01:09 PM	#6
Jeff Chambers Moderator Join Date: Aug 2000 Location: Milan, OH Posts: 2,699	What I was getting at was that I don't believe the 351 cam that he's running was designed for 1.5:1 rockers. I could be wrong, but its suspicious to me. Therefore, it might not really be giving the lift that you've calculated. The only real way to know is to do a vavle lift check at the retainer, and even then you'll have some valve train deflection that will decrease the effective lift. If he's not getting the lift that he thinks he's getting, then it might be impacting the rest of his combination. The engine won't make the power or sping the RPMs if he's shorting himself on valve lift; it directly affects the volumetric efficiency. Gears won't effectively change the powerband. You use gears to get you to the powerband that your engine is delivering. They do however provide torque multiplication. So a 4.10 gear is going to give you better leverage than a 3.55 gear. Lower numerical gears will allow you to run more MPH at a given RPM, while higher numerically gears will allow you to run more RPM at a given MPH. The specs on my cam are different than his....I'll leave it at that. __________________ Jeff Chambers 1990 Mustang GT 10.032 Seconds / 137.5 MPH 14-time Street Warrior World Record Setter CRT Performance 2001 Tropic Green Mustang GT - 12.181 / 113.2 MPH 2002 Ford F-250 Crew Cab 7.3l Power Stroke - 17.41@77.2 "There's nothing boring about a small block automatic shifting gears at 9400 rpm!"