changing a 1967 3-speed to a 4-speed

[MustangLove_67]

I have a 1967 Mustang that is a 3-speed and has had a 351 Windsor motor put in instead of the 289 it came with originally.
When I drive it and reach third gear the engine feels like it wants 1 more gear to reach a comfortable place. This being said, I
want to put in a 4-speed transmission. my questions are:

Is it Possible to do this?
What is the best way to do this?
What is the best Transmission brand to use?
Will a 4-speed transmission fit?

I would appreciate any feedback on this I can get. The more the better.
Thanks

 

[Realmongo]

Unless you install an overdrive it won't be any different, because the 3 and 4 speeds are direct. The car may have a low rear axle ratio.

 

[AeroCoupe]

TKX swap is in your future.

67-68 Mustang 5 & 6 Speed Conversions - Modern Driveline

67-68 Mustang 5 & 6 Speed Conversions, compete T5, TKO or T56 kits, Bellhousing to slip yoke or driveshaft & everything in between.even hard to find items

www.moderndriveline.com

 

[manicmechanic007]

It's worth more money with a toploader in it
The final drive is 1:1 on both the 3 speed and the 4 speed

 

[AeroCoupe]

Yeah but its not original with the 351W in it and a IMO the toploader is a boat anchor. I say this as I have driven a car with one and the shifting on it compared to my TKO was night and day. Toploader had a complete Hurst setup and my TKO has a Pro 5.0 and there was absolutely no comparison as the TKO was so much better and they are notchy as hell compared to a TKX.

 

[WORTH]

Yeah but its not original with the 351W in it and a IMO the toploader is a boat anchor. I say this as I have driven a car with one and the shifting on it compared to my TKO was night and day. Toploader had a complete Hurst setup and my TKO has a Pro 5.0 and there was absolutely no comparison as the TKO was so much better and they are notchy as hell compared to a TKX.

I've driven a crapload of toploaders over the years, and love them. I actually just cut a deal with a guy for a wide ratio that I'm going to slip into my '55 T-bird to replace the 3 speed. With the wide ratio the first gear is lower so I can go with a higher rear and get thee top end a bit more comfotable on the hyway.

 

[WORTH]

Unless you install an overdrive it won't be any different, because the 3 and 4 speeds are direct. The car may have a low rear axle ratio.

Hey old man, nice to see a couple of us are still alive. What's your current project? I've got 2 left in me. A '66 F-175 4x4 Mod and a slightly modified '55 T-bird, then I'm gonna drive-em 'til I die.

 

[Realmongo]

I still have 4 Mustangs. The 2017 'Vert has about 10K miles on it now and the wife wants to keep that one for road trips. The '84 T-Roof will probably go up for sale this spring. The '64-1/2 is still sitting in the CONEX where it has been for the past 20 years. So, that leaves me the '65 coupe that's been through paint and now needs to be reassembled. I've been spending most of my time working on old Ford farm tractors.