HELP 6 Speed

[Spartacus1]

OK, Some might laugh but give me a break. I know the JDM sr20 from a s15 Silvia came with a 6 speed. My question is this, since i can't buy a silvia can a buy the 6 speed tranny from one and bolt it on to my 1993 300zxTT, it has a 5 speed already on it i just would like to have the only 6 speed in town. Thanks for any help guys. I appreciate it.
~Spartacus1~

[misnomer]

I wouldn't expect the bell housings to line up, not to mention possible issues with the speed sensors, driveshafts, and whatnot. Why switch out for the six speed? YOu have essentially the same first and fifth gears as in the gearbox on the 240 (which iirc is identical gearing to the NA Z).

Anyhow, as always, anything is possible with enough money. I would say with near certainty that it is no simple plug and go. In my opinion, it is a bad idea anyhow. I haven't driven a TTz, so I don't know what drawbacks you have with the stock gearbox. I wouldn't give up my 5spd for a 6spd on my 240. . .

[Spartacus1]

There aren't any drawbacks i just needed to know if it was a simple swap or difficult and not worth it. Thanks for the help. Maybe some more people will give their 2 cents and advice.

[Yoshi]

actually, even if it did bolt up, it probably wouldn't be worth it, expecially for a z32. The s15 6spd tranny, if I recall correctly, doesn't give any higher of a final drive ratio, additionally there squeeze 6 gears into the same housing that formerly was 5 gears, thus thinner gears and not as strong. Drifters in japan running high boost will often swap their s15's 6spd for the 5spd of the s14 or s13 becuase they can take more abuse from tranny torturing things like clutch kicks. A z32 TT, making more power, would be at more risk to break the tranny than a s15... so even if it did bolt up, it wouldn't be worth it.

[DuffMan]

I think it has been determined that the 5spd bellhousings and 6spd are not interchangeable, so basicly it would be impossible unless you want to do custom work.

It would be easier to get a T56 which would hold more torque anyway.

[AceInHole]

Originally posted by Yoshi
additionally there squeeze 6 gears into the same housing that formerly was 5 gears, thus thinner gears and not as strong.
but... the housings aren't the same.... IIRC, people are just speculating that since they share the same mounting points, they're the same size... but i've never seen it been confirmed that they indeed are. i.e. if the output shafts are the same size, then yes, the gears might have to be "squeezed" in. that hasn't been proven though.

Drifters in japan running high boost will often swap their s15's 6spd for the 5spd of the s14 or s13 becuase they can take more abuse from tranny torturing things like clutch kicks.
couldn't it be that they swap to a 5 speed because they're cheaper?? Aren't people blowing up the 5speed transmission as it is??

[AceInHole]

Originally posted by DuffMan
I think it has been determined that the 5spd bellhousings and 6spd are not interchangeable, so basicly it would be impossible unless you want to do custom work.

It would be easier to get a T56 which would hold more torque anyway.

You're implying that the S15 SR differs from the S14 SR at the block, but IIRC, they don't.

[Jeff240sx]

Z32 and S chassis transmissions will not swap. Chris May toyed with the idea, and never went through with it. For someone with a 438rwhp 4-cyl.. I don't think that he would just drop the z32 idea without some major problem.
-Jeff