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 :(

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!

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 :(

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

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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" THE BLACK PARALYZER" -87GT 3800SC Series III engine, custom ZZP /Frozen Boost Intercooler setup, 3.4" Pulley, Northstar TB, LS1 MAF, 3" Spintech/Hedman Exhaust, P-log Manifold, Autolite 104's, MSD wires, Custom CAI, 4T65eHD w. custom axles, Champion Radiator, S10 Brake Booster, HP Tuners VCM Suite.
"THE COLUSSUS"
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" ON THE LOOSE WITHOUT THE JUICE "

Thank you guys for the help i guess i wont worry about it.

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84 stock :(

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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Dr. Ian Malcolm: Yeah, but your scientists were so preoccupied with whether or not they could, they didn't stop to think if they should.
(Jurassic Park)

The Ogre's Fiero Cave

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