kynovanut

iTrader: (2)

Is the main shaft length on the LS T56 the same as the 03-04 Cobra T56?

The reason I ask is, I purchased a conversion kit consisting of a cobra tail housing, cobra shift rail, and cobra main shaft. I did this to move my shifter location forward in my Chevy II.

The weird thing is, the Cobra Housing is 1 3/8" longer than the LS but the mainshaft length is identical.

So... Whats going on?? Did I get the wrong mainshaft for my conversion?

Jonathan@Tick

iTrader: (5)

The cobra mainshaft is longer and the difference is likely the same difference you are seeing with the tail housings.

Are you planning to mount a speedo reluctor in the transmission? The GM one isn't going to work with the Cobra shaft.

A cobra mainshaft would also be made differently where the 5/6 driven gear presses on. The GM gears will still work on the Cobra shaft, but technically it isn't right.

You could do a viper mainshaft (30 spline) which is the right length for the cobra tailhousing. It would also be made correct for the 5/6 gm driven gear. This would require the tailhousing to be machined for a larger output bushing and seal however...

Jonathan@Tick

iTrader: (5)

One other thing to note, the cobra tailhousing uses steel washers on either side of the reverse idler gear. An LS1 f-body tailhousing does not. If you are transfering the reverse idler gear from an LS1 tail to the cobra tail you will need 1 of the steel washers to go between the reverse idler and the cobra tail.

kynovanut

iTrader: (2)

Thanks for the heads up. That is the plan. LS trans with cobra tail housing and shift rail with viper mainshaft.

I have a friend who can machine the tail hsg for free.

Any other pitfalls I should be aware of?

This is my first T56 I've torn down and only the 2nd trans I've ever worked on.

Jonathan@Tick

iTrader: (5)

You will need a couple of spacers and a special speedo rotor if you want a functional speed sensor. The viper shaft doesn't use the same spline speed rotor or the same location in order to work with the viper tail.