Gearbox thoughts
Turbo Mini Forums

Hi guys and gals

I am unsure what to do about my project and what gearbox to go for. At the moment, I have 3 gearboxes sitting in the garage and not sure which one to use.

The first is the standard one out of my SPI that has a ratio of 3.105
The next is the standard one out of the metro turbo motor. I have no idea what the condition of this is or how many miles it has done.
Finally, I have a MED SC gearbox that is a staright cut, close ratio with a quaife ATB and straight cut crown wheel pinion.

I am going to be overhauling the metro turbo motor and putting it in the mini but not sure which box to go for. I bought the MED one as a mate was selling it and was going to put it in but now I am thinking otherwise.

With a turbo motor, would the close ratio box be too much?

I will be running 13's on the car so would this make a difference to what to go for?

I am more use to driving impreza's, evo and m3's so like the longer ratios. Would I be better off rebuilding the metro box to a spec that suits me better?

Thanks

Speed doesn't kill, suddenly becoming stationary, now that's what'll get ya!

use the med sc one

the MED box sounds the ticket, but the SC final drive may be to short,

I would suggest using the SPI 3.1 final drive, But I suspect it wont fit the ATB as there is an early type that takes LSD type crownwheels with no middle, and later ones that take std crownwheels.

Cheers for your replies.

I am not sure about what to do.

I bought my Mini for £1,300 and plan to strip it down and rebuild it from the ground up. So far, what I want to buy and what I have bought is going to cost £5,000.00 in total (that includes the price of the car). That isn't going to get me anything special. Maybe a rebuilt metro turbo engine but no real performance mods.

I was considering just using the standard metro turbo engine and box for the time being and sell the MED box to get a bit more cash for the project.

What do you reckon?

Is 5k for the whole project too much?
Should I sell the MED box so that I can afford something decent for the engine like an uprated cam?

Speed doesn't kill, suddenly becoming stationary, now that's what'll get ya!

Sooner or later with a running turbo engine you will want to turn the boost up, when you do this you will destroy a std gearbox before too long, hence I would hold onto the SC box.

do not trade the box for a cam that would be stupid imo, for the engine you want to start from the bottom up, good box is almost essential drop gears and bottom end, a reground crank is more than up to the job, same with the rods,
i would spend money on the pistons and the gearbox (which you already have)
after that all the go faster bits are bolt on and you dont have to worry about braking bits

keep the quaif atb if you can, ditch the final drive for the longer one jobs a good un

Yes i moved to the darkside

Instagram @jdm_brett

[joke mode]Don't listen to these guys I'll swap you an avonbar phase 2 and a box of quality street for the gearbox and diff[/joke mode]

Seriously don't let the SC go, you will regret it.

If something is worth doing, it's worth doing half of.

No, no no! sell it to me! :)

use the MED box (providing all is in good order). It is a good stong basis for the rest of the build. As Tom says, you will eventually need it anyway when the power increases