Safe rpm for cam?
06-18-2008, 12:45 PM
#1
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Car: 91 rs
Engine: Blow through 383, 10 psi, xr288hr
Transmission: Manual th350 ATI 3000
Axle/Gears: 3.50 9"
Safe rpm for cam?
Comp xr288hr 236/242 .520/.540 not including 1.6 RR.
Comp 977 springs 441 lbs/in
383 motor, I figure peak hp is around 6k rpms. Maybe 6500 with the blower.
Figuring my trap speed at 130+ a little with TCI's calculator, puts me around 6800 rpms. At low boost levels.
4.11 gears, th350. I really need to change gears.
The motor should be good for 7500 rpms, but I'm wondering how the hydraulic lifters will take it.
Whats a safe rpm limit? I will have to adjust boost accordingly.
Comp 977 springs 441 lbs/in
383 motor, I figure peak hp is around 6k rpms. Maybe 6500 with the blower.
Figuring my trap speed at 130+ a little with TCI's calculator, puts me around 6800 rpms. At low boost levels.
4.11 gears, th350. I really need to change gears.
The motor should be good for 7500 rpms, but I'm wondering how the hydraulic lifters will take it.
Whats a safe rpm limit? I will have to adjust boost accordingly.
06-18-2008, 02:07 PM
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Car: 1982 Trans-Am
Engine: 355 w/ ported 416s
Transmission: T10, hurst shifter
Axle/Gears: 10 bolt, true-trac, 3.73
Re: Safe rpm for cam?
I don't think your valve train can handle over 6500RPM.
06-18-2008, 02:41 PM
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Car: 91 rs
Engine: Blow through 383, 10 psi, xr288hr
Transmission: Manual th350 ATI 3000
Axle/Gears: 3.50 9"
Re: Safe rpm for cam?
Thats what I was looking for, I never bothered with the rev kit because peak power shouldnt be above 6500. I'm going to have to get different gears to run any kind of power.
06-18-2008, 03:09 PM
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Car: 82 Berlinetta/57 Bel Air
Engine: LS1/LQ4
Transmission: 4L60E/4L80E
Axle/Gears: 12B-3.73/9"-3.89
The rev kit takes a lot of load off of the valve spring. Compare the weight of a roller lifter to that of a valve - the rev kit takes all of the lifter load off of the valve spring, and therefore off of the wobbly push rod and rocker train.
Cheap insurance, even at 6500 RPMs.
Cheap insurance, even at 6500 RPMs.
06-18-2008, 04:18 PM
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Car: 91 rs
Engine: Blow through 383, 10 psi, xr288hr
Transmission: Manual th350 ATI 3000
Axle/Gears: 3.50 9"
Re: Safe rpm for cam?
Yeah, good insurance no doubt, but money is tight, and I could spend the 150 bucks on lower # gears.
On the street I dont go past 6000.......usually. My valvesprings are a little stronger than the ones comp suggests. They recommended the 986.
I'm either gonna just have to run the 1/8 mile or run like 3 lbs of boost. Until I get new gears....
On the street I dont go past 6000.......usually. My valvesprings are a little stronger than the ones comp suggests. They recommended the 986.
I'm either gonna just have to run the 1/8 mile or run like 3 lbs of boost. Until I get new gears....
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