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RPM range for a 455 pontiac with a T-400 and 3.07 gears to turn 3200 RPM at 60 mph? This is with a 29" tall tire. This combination is in a 48 Chevy Sedan delivery.
A buddy of mine is having a dilemma about this. His Tranny guy is telling him that the RPM range is acceptable for the combination. But he really doesn't like turning the motor that high on the Interstate. He is also concerned about the cost (and reliability)of changing to a 700 R-4.
Thanks in advance for the help.
Chris
Those are 4.11 gears or the torque converter is slipping bad...........
4.11 , 1 to 1 in drive with a 29 inch tire should be......
4.11 gears
Engine Speed (RPM) Speed (MPH)
8000 RPM 167.93 MPH
7500 RPM 157.44 MPH
7000 RPM 146.94 MPH
6500 RPM 136.44 MPH
6000 RPM 125.95 MPH
5500 RPM 115.45 MPH
5000 RPM 104.96 MPH
4500 RPM 94.46 MPH
4000 RPM 83.97 MPH
3500 RPM 73.47 MPH
3000 RPM 62.97 MPH
2500 RPM 52.48 MPH
2000 RPM 41.98 MPH
1500 RPM 31.49 MPH
1000 RPM 20.99 MPH
This is what the 3.08 should be......
Engine Speed (RPM) Speed (MPH)
8000 RPM 224.09 MPH
7500 RPM 210.09 MPH
7000 RPM 196.08 MPH
6500 RPM 182.07 MPH
6000 RPM 168.07 MPH
5500 RPM 154.06 MPH
5000 RPM 140.06 MPH
4500 RPM 126.05 MPH
4000 RPM 112.05 MPH
3500 RPM 98.04 MPH
3000 RPM 84.03 MPH
2500 RPM 70.03 MPH
2000 RPM 56.02 MPH
1500 RPM 42.02 MPH
1000 RPM 28.01 MPH
This is with a 4.56 rear gear ,this looks the closest to the rpm he is turning
Engine Speed (RPM) Speed (MPH)
8000 RPM 151.36 MPH
7500 RPM 141.90 MPH
7000 RPM 132.44 MPH
6500 RPM 122.98 MPH
6000 RPM 113.52 MPH
5500 RPM 104.06 MPH
5000 RPM 94.60 MPH
4500 RPM 85.14 MPH
4000 RPM 75.68 MPH
3500 RPM 66.22 MPH
3000 RPM 56.76 MPH
2500 RPM 47.30 MPH
2000 RPM 37.84 MPH
1500 RPM 28.38 MPH
1000 RPM 18.92 MPH
Thanks Shawnlee. I will pass this on to him.
It sounded really weird to me when he told me what RPM he was turning.
Mines a 383 TH350 with 410s and 26" tires-- Thats about where its at I agree with Shawnlee
Yup... something doesn't add up... I'm running 4.56:1 with 31" tire ~65-70 at 3200-3400rpm