Rpms at 60? (Page 1/1)
gb.84.fier0 MAR 04, 09:39 AM
I have a stock 84 with the 3 speed auto trans, and im running 2500-3000 going 60 without the cruise because it doesnt work, and im just wonering if thats normal? It seems too high even for an 80s car.

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84 stock :(

css9450 MAR 04, 10:21 AM
Well, a little maybe. Keep in mind the factory tach is 37 years old and as they age they tend to read high. Some people's tachs read much, much higher!
gb.84.fier0 MAR 04, 10:33 AM
thank you for your input, this is the first 80s car i have owned, let alone a fiero so i wouldnt really know.

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84 stock :(

FieroWannaBe MAR 04, 11:38 AM
Assuming a stock 1984 Fiero, on stock tires (215/60R14), with the factory TH125, 3.18:1 final, in third gear (1:1) with a working torque converter lockup, cruise RPM at 60MPH should be 2655 RPM
Dennis LaGrua MAR 04, 12:28 PM

quote
Originally posted by gb.84.fier0:

I have a stock 84 with the 3 speed auto trans, and I'm running 2500-3000 going 60 without the cruise because it doesn't work, and I'm just wondering if that's normal? It seems too high even for an 80s car.




Depending on the FDR that sounds about right. You really can't have an auto with a low ratio FDR when you have 95 HP. That car wouldn't get out of its own way. If you want lower RPM cruising and much better gas mileage the 5 speed is the way to go. Some owners report up to 50 mpg with that combo.

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gb.84.fier0 MAR 04, 01:41 PM
Thank you guys for the help i guess i wont worry about it.

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84 stock :(

theogre MAR 04, 01:47 PM
There is "simple" math to tell engine RPM at a given speed and gear...

RPO label in front near brake MC should show trans "final" gear.
then See my Cave, Gear Ratio


Note:
Many AT has TCC disconnected or "dead."
Watch tach at highway speeds then push brake pedal just a bit. Don't try to slow or stop. Tach Should go Up ~ 200rpm then down when release the pedal.
⚠️ Warning: Don't test in heavy traffic or w/ someone behind you. Rear Brake lights should be On when RPM changes.

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(Jurassic Park)

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[This message has been edited by theogre (edited 03-04-2021).]