Clutch question

[RadarvT]

Hi guys, hope you can help.

My fundamental question for this post is: what's the difference between a 5 speed clutch and a 6 speed clutch?

I'm finishing a 5 to 6 speed conversion on a GTO 3. I'm the 4th place to have a go at it. When I received it it had the engine and gearbox in place. I'm not sure what clutch assembly is installed, whether it is 5 or 6 speed. What I can tell you is that in bleeding the clutch I have now blown two slave cylinder/release bearings and am about to pull the engine tomorrow for the 2nd time since it's been with me. I'm getting well practiced at this.

Clearly the cylinder is trying to throw too far and 'popping off then end'. So £700 worth of slave cylinders gone up in smoke, I don't want to make it £1k, especially as the lead time on these is quite painful.

Next question: Has anyone tried pulling the 'top hat' off the Noble supplied slave cylinder/bearing and fitting it to a standard Ford assembly? Can you press it off the old one and heat it up and drop it on the ford part? Freezer for the Ford part and oven on max for the 'top hat'?

Thanks in advance.

[andygtt]

I do know that the 5 speed clutch won't work in a 6 speed box as i did this conversion years back... the 5 speed throw bearing is longer than the 6 speed (I just put them on the bench next to each other to check), however this tells us nothing as the mountings of each are different so they could start in a different position to the clutch/flywheel anyhow.

The noble 6 speed bearing is just a modified ford item, they just put the steel spacer on the front, you could just remove it from one of your new ones and have it fitted to a new (much cheaper) ford bearing.... alternatively if you do actually have a 5 speed clutch, you could have a new spacer made for the ford bearing that reaches the clutch fingers...It would involve a bit of measuring etc.

6 speed clutch is pretty expensive, i had to buy a new item and it was around £700 new for the complete unit.

The good news is the flywheel for the 5 and 6 speed are identical

[RadarvT]

Thanks Andy,

Turns out there was a very old 6 speed friction plate with a 5 speed pressure plate... I had the correct 6 speed plate in a pile of spares that came with the car. There was no way the friction plate I had was going to cope with the upgraded engine in any case so I've obtained an upgraded friction plate and pressure plate that costs less than a standard one and with the exchange bits that's reduced the cost significantly.

As time is now a concern with this project, I've just gone with yet another Noble branded release bearing.

Roll on tomorrow...

[CaptainPeter]

I've got a M400 standard clutch in the garage if anyone is interested.