What is the appropriate transmission for a Daytona Coupe

[Brandonk603]

Hi Everyone,

Im new to this forum and have to say im extremely impressed with the amount of knowledge all of you have as well as the support you give to each other to solve someone elses problem. With that said I know im in the right place and looking for advice and opinions on the right transmission. Ive been waiting a long time to build a car and the Daytona Coupe is at the top of my list. I did visit Factory Five for a partial showing due to Covid and was able to ask lots of questions but lots more came up after the fact.
One being the transmission which ive been on the hunt for. Im using a Ford 351 Windsor and have no intentions on racing but do plan to drive it often including highway driving. I do know im limited to a Tremec TKO 600 or T56. I really dont have any experience with engine building or cars for that matter and want to make as few big mistakes as possible. I see a lot of transmissions on Ebay (5 speed, 6 speed, gear ratios, ect!)
Also maybe most important is my wife wants to drive it occasionally so I HAVE TO keep her happy:)
Im still months away for ordering the kit but wanted to start with the engine and transmission.
Thanks,
Brandon

[Gordon Levy]

Both will work, what determines which one depends on rear gear ratio, how aggressive your engine is cammed and how you want to use it. There is also the cost different between the 2 that may be a factor.

[edwardb]

Like many build choices, "appropriate" is in the eye of the builder, and most including myself will recommend the choices we personally made. Having said that, echoing what Gordon said, either a TKO or T-56 will work fine. TKO is a bit cheaper, smaller, and lighter. But is 5-speed, and I'd highly recommend only considering the 0.64 final drive version. Especially considering your comment about doing a lot of highway cruising. The T-56 is bigger, heavier, and more expensive. The good news is it fits into the Gen 3 Coupe easily and without modifications. I've had TKO's in Roadsters and now a T-56 in my Gen 3 Coupe. (Build thread in sig line below.) I do like the T-56 better. The two overdrive ratios are nice making the gaps between 4-5-6 less extreme than the 4-5 gap with the TKO. It shifts better and I like the reverse lockout feature. Although that's an added complication not necessary with the TKO. You will need to decide pretty early on as the driveshafts are different and also the bell housings are different. I'd also highly recommend studying your rear gear ratio. They are geared differently and you may not find the same differential ratio is optimal for both. I use this tool to analyze. https://www.tremec.com/calculadora.php. Good luck.

[Brandonk603]

Thankyou guys! Thats valuable information and have been leaning more towards a 6 speed. I would rather spend the money now with no regrets so im not pulling the transmission out a year after the build is complete. I will spend time looking into gear ratios to determine the best options for driveability.
This is my first build and want it to go as straight foward as possible and would really hate the idea I may be cutting out crossmembers to make a trans fit as I see that has happened to some of you.

[afd660]

I agree with edwardB on the 6 speed. But that's what the 5 speed is, 1-4 is pulling gear and 5th is definite highway. Would be nice to have that extra gear most of the time. But on the other hand I do like the 5-4 downshift though.

[GoDadGo]

A 6-Speed is the only way to go which is problematic for the MK-4 Roadster because of where Factory Five located the engine and the stubbiness of the wheelbase which is only 90".
If I were going to build a Daytona, then the only transmission I'd stuff in it would be a T-56 because it is buttery smooth like my ZF gearbox and is still in production.
The fact that Factory-5 stretched Daytona's wheelbase to 95" makes it possible to likely run a 3-Link rear if you desire a solid axle over the I.R.S.

Good Luck In Your Quest From The Dark Dart Side!
https://www.factoryfive.com/whats-new/customer-steve-l-graduates-his-mk4-roadster/

[Bob Cowan]

If it were my car, I'd install a 6R80 six speed automatic. Very easy to drive, comfortable in traffic (cruise night), and shifts faster and smoother than I ever could.