question about Zs tranny...

BGTV8

The only reason the tyres break loose is because the torque down the driveline has peaked high enough to overcome the grip of the tyre.

Picture it this way.

A gearbox is a torque multiplication device. 1st gear ratio is 3.7949:1, 2nd gear is 2.3248:1.

The size of the teeth in the gearbox is approx 14mm wide and about 5mm tall. On average, there are two teeth engaged on any gear at any point in time. The engine makes 363Nm at 5200rpm. Therefore when you pop the clutch in 2nd gear, the two teeth transmitting the full torque load (363Nm) have to do this with a surface area of 2x14x5 sqmm or an area of 1.5 sq cm .......... now Mr Nissan has engaged some reputable engineers and selected the finest steel money can buy (if you beleive this, then welcome to the land of the tooth fairy).

And you ask whether it will shorten the life of the transmission. Can I suggest that the answer might well be "yes" ......

The shock load is akin to hitting these two teeth with a 36Kg hammer swinging thru an arc of 1 metre - the pressure would be 36kg per 1.5sq cm .... I am hoping that Mr Nissan's metalurgists know their business.

I suspect that if you continue the mechanical abuse of your motor vehcile in this manner, you need to make a dentist's appointment (for the teeth on the gears in the gearbox of course, not for you!!).

Sorry - I forgot ... the load is roughly doubled because of the multiplciation effect of the 2nd gear ratio ..... although only the tyre will see that load.

Oh ... by the way, if you trawl back thru recent posts in this forum, two cool dudes who sort of did what you did with the Evo dude finshed up in front of a judge and 12 of their fellow citizen's trying to explain culpable driving as an "accident". Save the racing for the track please - it is much safer that way.

RB