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Opel Rallier since 1977
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Just google 'getrag 240 gear ratio opel'. I am seeing .804 for 5th gear. Just multiply that by your top gear RPM (3500) to see how much it would drop in high speed cruise mode (5th gear).

FWIW.... the original Manta Rallye with the 3.67 rear gear would cruise at 65-70 mph at 3300 RPM.... it was not a big issue that I ever can recall.
 

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Just google 'getrag 240 gear ratio opel'. I am seeing .804 for 5th gear. Just multiply that by your top gear RPM (3500) to see how much it would drop in high speed cruise mode (5th gear).

FWIW.... the original Manta Rallye with the 3.67 rear gear would cruise at 65-70 mph at 3300 RPM.... it was not a big issue that I ever can recall.
I always swapped rear ends on the Manta when I made the "Fla run" and would swap back when I got home. Got better Gas mileage that way. I've always been a cheapskate.:lmao: Jarrell
 

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Über Genius
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I've added a 3.67 differential and Getrag transmission to the calculator
 

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Your Noble Friend ;-)
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I've added a 3.67 differential and Getrag transmission to the calculator
You have not included slippage in your calculation. Depending on the speed, you lose between 1% and 3% of your speed in slippage between the tire and the road.

Dieter
 

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You have not included slippage in your calculation. Depending on the speed, you lose between 1% and 3% of your speed in slippage between the tire and the road.

Dieter
You, re right. I'd never add slippage to a calculator like this because it's not relevant.
I also don't have different tire sizes. I also don't add the weight of modifications or the differences in driver weight or tank capacity.

I'm not an engineer. I'm a hobbiest.
 

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You have not included slippage in your calculation. Depending on the speed, you lose between 1% and 3% of your speed in slippage between the tire and the road.

Dieter
So every time we drive it's a long slow burn out ? :) And don't forget that the centrifugal force makes the tires grow and thus increasing the speed so you gain back the lost speed. :) One more thing, if there are a lot of insects in the air inside the car, does it increase the vehicle weight ?:p
 

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Very long slow burn out indeed!
 
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. All I can remember was somebody had it up East Coast? Decided they didn't want it, I bought it bolted it up, got stuck on the shifter part fabricating, and stopped;.




You had someone pick it up for you at Carlisle. I imported the trans from Norway..
 

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Don't forget to adjust for dimensional changes due to over/under inflation and thermal expansion and contraction.
 

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Opel GT Transmissions for sale.

$50 each + shipping. via Paypal Goods and Services (buyer pays fee). (Price negotiable, I'm new to the world of Opels!) (Edit, why is the forum saying values are so low, but ebay prices are much better?)

Please feel free to ask any questions.

Lots of parts available for local pickup in Austin, Texas.
How do I get in touch with you?
 

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