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5 Speed Swap- Ratio ?

BMosely

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68 Coronet going from the 318 motor/727/3.23 rear to 440 motor/TKX 5 speed/3.55 rear. Daily driver is the end goal. The options below are Wide or close.
Gear Sets:

Wide
3.27, 1.98, 1.34, 1.00, 0.72

Close
2.87, 1.89, 1.28, 1.00, 0.81 or 0.68

SST has recommended the close. Anyone have some experience with the swap and have some input? Also, if close choice, .81 vs .68 on the O.D.
Thanks.
 
I would go with the close just to get the .68. With 3.55 you should have plenty for the low end and with .68 you will love going 70-80. Here in az. we have some 75 limits on the highways and nobody gets a ticket for going 80.
 
I have a 340 with the 5 speed TKO 600 (3.55 gears like you want) and I believe I have the close ratio transmission. My ratios are almost identical at 2.87, 1.89 , 1.28 , 1.00 , 0.64 (slightly different than the 0.68) but I am running 1900 RPM at 70 mph and right at 2000 rpm at 75 mph I can be at 90-100 mph and still be less than 3000-3500 rpms and the car feels right at home. I took a 400 mile road trip back in October and I got 15.8 mpg's at 75 mph. It's a completely different car than one with a 727 and it will be the best investment you ever make in drivability. Just my opinion though.
 
I have a 340 with the 5 speed TKO 600 (3.55 gears like you want) and I believe I have the close ratio transmission. My ratios are almost identical at 2.87, 1.89 , 1.28 , 1.00 , 0.64 (slightly different than the 0.68) but I am running 1900 RPM at 70 mph and right at 2000 rpm at 75 mph I can be at 90-100 mph and still be less than 3000-3500 rpms and the car feels right at home. I took a 400 mile road trip back in October and I got 15.8 mpg's at 75 mph. It's a completely different car than one with a 727 and it will be the best investment you ever make in drivability. Just my opinion though.

I knew the top side would be fine, my concern is first gear and clutch engagement. How is is out of the hole with the 2.87? Do you have to ride it a little or is is pretty strong on the engagement?
 
I knew the top side would be fine, my concern is first gear and clutch engagement. How is is out of the hole with the 2.87? Do you have to ride it a little or is is pretty strong on the engagement?

That's tough for me to answer because I am not skilled enough to know what "good" engagement is and it somewhat subjective. I have not driven a ton of different manual cars so I don't know what to compare it too. When normally driving in stop and go traffic, I do have to ride it somewhat but I would also say it has good engagement as well. It honestly reminds me a lot of the T5 transmission I had in my 2002 mustang GT if that helps for a comparison. I'm really sorry, I'm not sure I am helping at this point.
 
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