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Normal rpms

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aroostok

Jedi Hopeful
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Just had an engine rebuild on my 76B with dual HS4's. Can anyone give me an idea as to what normal rpms would be in 4th gear (no overdrive) at around 55-65 mph. Have been seeing around 3600 at 55 up to about 4000 at 70. Does this sound right? Thanks
 
About so - but maybe somebody near their MG can go out for a run & give you specifics

Do you have a hand held GPS? If so, you can use it to verify your speed.
 
what size tires?

My 75's rpm is 4k at 75mph. I cant remember off hand exactly the rpm at 55 and 65mph but I belive its a little bit lower than what you have posted.
 
In top gear (no OD), my tach has the same angle of inclination as my speedometer. Which comes out to APPROXIMATELY 3000 @ 55, 3500 @ 60, 4000 @ 70, 4500 @ 75, 5000 @ 80, etc. The actual RPMs might be a touch lower, but that's the rough neighborhood that my tach reads at those speeds.
 
I do know that 5000 rpm in OD is around 110 mph!
 
David - if that was after dark, I hope those huge driving lights were on.....hehehehehe
 
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