Tremec T5 or TKO 600

[sierrabc]

Sorry for what may be a stupid question but can someone please tell me if I should be using a Tremec T5 or TKO 600 for my MK4 build? I`m going with a Ford Racing 427 based on a 351W block? Also close or wide ratio with 26 or 31 spline?

Thanks,
Sierrabc

[CdnCobraGuy]

I believe the 26 vs 31 spline question needs some clarification. the TKO uses a 26 Spline input shaft and a 31 spline output shaft where as the T5 uses a 10 spline input shaft and a 28 spline output shaft. Ergo I beleive the question becomes moot once you settle on a transmission.

The T5 is rated at 300 Lbs of torque, but remember that rating is for a typical 3800 Lb car and in my experience with the 2300Lb Cobra you will break traction long before you break gears unless you are totally insane with powershifts etc. I have many customers running 400+ hp and similar torque on a T5 in a Cobra without problems.

That all said the TKO is a much stronger transmission so if you want to be really confident and you wallet can afford it I would say go with a TKO. In addition the shifter location can be easily moved to any one of eight positions with a TKO so if you wanted to move it forward in the Cobra you have that option.

As for the close vs wide discussion this pretty much depends on your driving style. The close ratio is better at keeping the engine within its peak torque range but will see you shifting more often as you will not have the big drop in engine speed as you shift gears. In addition the close ratio has a taller overdrive which will reduce engine RPM more in top gear so on the highway you will get better mileage (read as range on a full tank) with less 5th gear "snap" where as on the salt flats or a race course your top speed could, in theory, be higher provided your engine has the power to overcome the increasing drag as speeds rise.

All food for thought

[DougR]

TKO and you'll have no regrets.

[sierrabc]

Thanks guys I really appreciate your insight.
sierrabc

[Bill_VA]

Also, with the TKO you have shifter position options. I really like my mid-shift kit. Give Mike Forte a call, he's a Tremec dealer.

[Bob Cowan]

A lot depends on what you're planning to do with it. Like Al said, a good T5 will survive street duty, if you don't beat it up too much. But if you're thinking about racing at all, get the TKO.

The TKO is heavier, and physically larger, and that can matter. It's also more expensive. But, if you're racing it will save you money in the long run.

I prefer the wide ratio, with a lower first gear. It's easier to drive in parking lots, up the ramp, into a trailer, etc. I like that low first gear.

The 427 stroker makes a lot of torque, and has a very flat curve. Lots of area under the curve. On the track, I only need to use 3rd and 4th, with an occasional forey into 5th when conditions are right. With a narrow ratio I might be shifting more, and that costs time.

More splines means a larger input shaft. Not much larger, but a little. That's why the higher spline count can handle more torque.

When I built my car, I had no intentions of racing. But, I wanted the strongest part I could use, and never worry about it again. So far, it's holding up just fine.

[joecamire]

Call Mike and get a mid shift TKO you will love it!!

[BigLeo69]

i went with a tko-600 for resale value if someone wanted or me too shoehorn a bbf with more hp it will handle the ft.lbs

[mike forte]

Hi Sierrabc,
The 427W you're using is way to much power for a T-5. Close or wide ratio really depends on your driving style, cruising speed, rearend gear ratio & more.
Have you picked a rearend gear ratio? Do you plan to race this in the 1/4 mile? Highway or back roads? Top speed or cruising?
Fill me in on what your plans are.
Mike Forte
508 875 0016


Sorry for what may be a stupid question but can someone please tell me if I should be using a Tremec T5 or TKO 600 for my MK4 build? I`m going with a Ford Racing 427 based on a 351W block? Also close or wide ratio with 26 or 31 spline?

Thanks,
Sierrabc

[Glory Bound]

I'm a newb but I agree with Mike. The TKO 600 handling 600 ft-lbs of torque was a big selling point for me. I have a console so went with the standard shifter location and with Kirkey high back buckets it works well for the street and so far as I learn to drive the car in AX and track events.