Can't find a large ID concentric slave, do they even exist?

[vlad01]

Hi all,

I am trying to locate a concentric slave with an ID of 40ish or more mm, maybe like 45mm ideally but I have come up empty handed after looking into this a few times over the last year or so.

My nephew's 4Runner has been off duty for mostly 3 years now due to crap quality conversion from Marks 4x4 and there are no other options on the market to fix the poor implementation for the V6 conversion.

I have got even a Malwood T5 hydraulic bearing on hand ($600+ ) and it's a no go due to the thickness of the input adapter. There is literally no way around unless I can find a bolt on concentric slave with north of 40 something mm, more around 45 is ideal but the biggest I have found is 35mm, a standard GM/ford size and 36mm as a bolt on (non sliding type). The bolt one type will allow me to stay a smaller ID where a slip on type will nee somewhere close to 50mm ID becasue the nose cone will need a sleeve extended and to go over the input and there is a min wall size practical , thus adding to the min ID requirement.

I've looked at probably 100 websites and technical drawings of all makes and brands and have come up with literally nothing.

I've even tried to look up truck concentric slaves but don't get much in the way of anything truck related, I would assume a truck would have a large input shaft but I have no clue about trucks other that they are diesel and normally have a trillion gears.

[hjtrbo]

The Toyota fork and throw-out bearing a no go? Would have presumed that to be all sorted.

[vlad01]

Nah, it's a complete cluster f**k that fork setup due to how far from the engine the trans actually is and the weird double bell housing with a spider cast into the conversion bellhousing that hold a long sliding metal tube that houses the bearing. I re-engineered it, it was off it's face but just the whole design is like polishing a turd on the best of days.

A concentric slave is the only way to make this work without a custom one piece Toyota/ Holden hybrid input shaft and a modified nose cone which obviously won't be possible.

[antus]

I know nothing about concentric slaves but from a bit of a google I found https://apracing.com/race-car/slave-cyl ... 0-cylinder which looks like it might be what you want with 50mm ID option if im reading it right. And says saab 900 family direct fit, so maybe thats an oem option? sorry if i've got it all wrong...

[hjtrbo]

That's only got a 30mm ID. Biggest ID AP do is 38mm on their 6000 series

edit: or was that Tilton 6000 series. I've forgotten, it was 1 of the 2.

[hjtrbo]

Can the adaptor mandrel be turned down and re-heat treated to 38mm just along the length that resides in the cylinder bore? I looked last night after reading your thread and got nothing anywhere near the 45mm you need.

[vlad01]

I could make it work with 38mm. I plan to turn it down anyway as part of it already has a narrower section at 34mm but it's exactly not where I want it to be narrower, actually the whole female part of the shaft needs to be the thinner diameter.

Will heat treating really be necessary? I already had the end machined and shortened as it had negative end float and destroyed the crank and bearings as a result. This had no negative effects on it while it was running.

[hjtrbo]

For perfection yes. The heat treatment usually hardens as a layer as opposed to all the way through the material. Once you cut through it on the lathe it's gone. The inside bore will obviously still be hard which is where all the work is being done. Are you turning it down yourself? You might need to shout yourself a ceramic insert.

[vlad01]

I'll be getting a machine shop to do all the work. I don't have the equipment or the means to do it at home.

[hjtrbo]

Disclaimer, I'm a home hack with youtube degrees. I would let them know the application and follow their advice.