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Discussion Starter #1
I started a post a little while back about my need for replacing my 4 speed toploader. I was replacing the clutch when I noticed the case has a broken "ear" where a bolt holds the tranny to the rear of the motor, (top drivers side) and there is also a leak that is soaking my clutch pretty good. I could stop the leak but there is still the 3 bolts vs 4 bolt issue, that I am not a fan of. I thought the tranny was original which it is NOT. This tranny is out of a 1966 Fairlane and is a WIDE ratio.

I do not plan on drag racing this car but would prefer to get rid of the shuddering acceleration that it has and strongly feel that this bolt issue is a pretty good starting point to resolve that issue. The tranny is on the floor so right now makes sense to do something.

My 1969 XR7 vert S code as per the Marti report came with a close ratio 4 speed. I believe the rear is supposed to be a 3.0 open rear.

I was talking to someone about replacing the 4 speed back to a close ratio and they thought that a wide ratio is better. Their feeling is that the car will be a pig getting off the line as well as MPG wise. I would like to have some get up and go mind you, but again, I am not going to go to the track. Let's just call it spirited driving. That is what I would like to have. I feel my 390 should help have a little of that.

I am just aking opinions here. My feeling is that now is the chance for me to get this car back to "original" equipment regarding the close ratio.

Is there really that much of a difference between the two? With either a C or W in 4th gear I will be 1:1 and my tach will be the same, right?

In a CLOSE ratio 1st is 2.32, 2nd is 1.69, 3rd is 1.29, 4th is 1.00 (slower off line)
In a WIDE ratio 1st is 2.78, 2nd is 1.93, 3rd is 1.36, 4th is 1.00 (faster off line)

RPM's will vary in 1-3rd but will equal out in 4th. Meaning same MPG

This car is basically original, the motor is original, new top, interior is original besides carpet.

I am just trying to get some thoughts here and I appreciate all reply's.

Thank you.

Bill
 

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Yes, 4th gear will be the same with either.
A 390 has enough torque to "get by" with the tall close-ratio first gear and 3.00:1 axle ratio, but its far from an optimal combination. Performance and driveability will be improved with the wide ratio gearbox. A close ratio transmission really needs 3.50:1 or steeper gears to work well. Although if the car is going to see a lot of highway driving and maximum performance isn't a primary concern, 3.25s would be a reasonable compromise. I'd really like to know what the the individual who ordered the car with a close-ratio transmission and 3.00:1 gears was thinking. Its an unusual combo, but unusual for a reason.
 

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I have a wide ratio 4 speed in my eliminator 351 4V. I dont have any problem with the amount of power I get from the car. When I kick in the 4 barrel it gives me plenty of grins. Gas MPG is about 12-13. It only has a couple of thousand miles on the engine. If the rear end is the same that it came with it has the 3:00 tration loc
 

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The wide ratio version is more fun to drive, regardless of engine size.
 

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Discussion Starter #5
You ask a very good question. I am not sure what they were thinking. But............the car is 1 of 42 1969 XR7 convertibles with a 390 motor and close ratio 4 speed transmission.

That right there is very rare.

Yes, 4th gear will be the same with either.
A 390 has enough torque to "get by" with the tall close-ratio first gear and 3.00:1 axle ratio, but its far from an optimal combination. Performance and driveability will be improved with the wide ratio gearbox. A close ratio transmission really needs 3.50:1 or steeper gears to work well. Although if the car is going to see a lot of highway driving and maximum performance isn't a primary concern, 3.25s would be a reasonable compromise. I'd really like to know what the the individual who ordered the car with a close-ratio transmission and 3.00:1 gears was thinking. Its an unusual combo, but unusual for a reason.
 
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