T45 or T56

[1998cobrasvt]

I wasn't saying go with the T56 because it holds more power - as I said in my previous post both the T56 and the T45 can be made to hold pretty much any torque you want.

The reason I said T56 over the T45 is because you get more gears. Period. Will the T45 work? Sure. I road race my Mustang with a 5 speed (T5). Does it work? Sure. The whole purpose of gears, and where I was going with the T56, is that engines have a range in which they operate best. The sole purpose of the transmission is to attempt to keep that engine in that efficient range as much as possible (via managing RPMS).

On the track, a Mustang typically has gobs of torque, over a range of RPMs. This allows more flexibility in number of gears for the transmission, meaning the driver doesn't necessarily always have to select the best gear to keep torque up (as they might in say a Honda, for example). Depending on the range of the torque provided (say, max torque made between 2900-3400 RPM) means that if your current gear box, when shifting, always drops you in this range, then you are fine. You don't necessarily need more gears. If your range is shorter, or specifics of the track require it (hairpins or really slow sections, etc.), then more gears means that the driver has more opportunity to be in an optimal gear (think coming out of a turn).

If I personally have the option of a 5sp vs a 6sp and the cost of the transmission is not an option, why wouldn't I go with a 6 speed? Will a 5 speed work? Sure. Will a 6 speed work better assuming I have the skill and experience to make use of it? Sure.

If the goal was to not spend money, then yes, go with the T45 and get seat time. But the question was: T45 or T56. In which case, T56. Also, FWIW, F1 cars, rally cars, etc. all have more than 5 gears. Could they make 5 gears work for them? Perhaps. But they have specifically chosen more gears for a reason. Again, my point being: will 5 gears work? Absolutely, and if money is an issue (as it is with me), they will work fine. Should you go with more gears if money allows it? Absolutely. Especially if one drives different tracks and doesn't want to actually swap gears between events (like pro teams do) - the 6 speed will allow one to have a better chance of having more optimal gears for different tracks.

Well put