hi,
i have mk indy with fireblade engine, ford donor using ford modified prop shaft attached to gearbox out put with UJ, "hard" mounted and bolted to the prop bolted to the diff.

when engaging gear and on some changes there is a nasty clunk noise and i am advised by AB performance that this is over time going to damage the gear box,

only done a few hundred miles so looking for options to reduce gear box damage.

i have heard of rubber integrated prop shafts that twist a little to absorb shock however they cost around £500. Im looking for a cheaper home build solution?

i have also read some build diaries where people have used Rubber mounts on to the gear box,

has anyone any experience with this and able to advise what can be done to help reduce wear?

much appreciated.

I have seen a few bike engine kit cars with a modified sierra propo shaft with the rubber shock abosorber thing.

When I got mine from DUNNING & FAIRBANK although I have been advised to rubber mount the diff if possible to make it a little less BANG.

Mine has not shock absorber in the prop and to the sierra diff hard mounted with the bike engine hard mounted too.

I havent had it out yet so I couldnt tell you what its like but I know that the propshafts dont tend to have rubber in them if bought new.

Lets see what others say :O)

Thanks, Will check them out and see what they got.

do you have solid connection then from gearbox to diff as i do? if so how long has it been like that, how many miles covered approx, any sign of g/b wear, what engine you got?

thanks
wes

I built my car without a TRT in the propshaft and it was very clunky after swapping to the TRT it was much better, but still has a fair few clunks. I would recommend the swap, I got mine from Bailey Morris.

whats TRT?

Torque Resiliant Tube

Mine hasn't been on road yet so couldn't comment mine is trt but has no rubber parts in it.

It will always clunk though. The prop is the same as my friends who had it for 10k at least but gearboxes ain't as strong as car ones.

£500?!

I got mine custom made from Bailey Morris for <£350 and they had it done in 2 days excaclty as I specified.

If you already have the propshaft, Dunning & Fairbank will replace the rear section of the propshaft with a Torque Resilient Tube (TRT - Basically, a tube within a tube bonded together with rubber)

We had ours done in 2005 and at the time, Dunning & Fairbank charged £120 to do the modification, which included balancing and painting. We've since done numerous track days, drag days and approximately 20,000 road miles and the gearbox is still strong.

Give them a ring to discuss - Dunning & Fairbank

Phil

[Edited on 29-7-12 by Hellfire]

Thank you all for your comments. Perfect answer to fit TRT to my existing prop shaft. And definately in budget. Thanks again