27 replies to this topic

[mini13]

the cylinder inline was a damper to prevent violent disengagement

[Spider]

Metros had a 5/8" master compared to  3/4" on a Mini. I've used one with a Pre-Verto & pre '76 pedal box.

 

It's been a very long time since I needed to look at mine, but yes, they are indeed 5/8"

GMC1010

https://www.euspares...rts/lpr/2361742

 

Good shout.

[croc7]

Metros had a 5/8" master compared to 3/4" on a Mini. I've used one with a Pre-Verto & pre '76 pedal box.

Thanks for the information. My engine is (was) a Metro 1275, so should be an easy swap. They are fairly hard to find but I did find a NOS one out of Cypress, of all places. Did it make a noticeable difference in pedal pressure?

Edited by croc7, 02 April 2022 - 01:42 AM.

[Spider]

 

Metros had a 5/8" master compared to 3/4" on a Mini. I've used one with a Pre-Verto & pre '76 pedal box.

Thanks for the information. My engine is (was) a Metro 1275, so should be an easy swap. They are fairly hard to find but I did find a NOS one out of Cypress, of all places. Did it make a noticeable difference in pedal pressure?

 

 

It should make the pedal about 12% lighter - if that's any help.

BUT

 

Before going down this road, just be sure you have enough pedal over-travel now or you might find you can't completely disengage the clutch. 

[croc7]

Thanks, Chris. Is that an adjustment at the clutch lever stop, the throw-out stop (at .125”) or combination of both??

To prevent damage to the crankshaft thrust washer, I thought that the .125” measurement at the throw out stop was set in stone.

J

Edited by croc7, 04 April 2022 - 03:28 AM.

[Ethel]

I have to admit I can't say how much lighter because I never tried it (grey diaphragm) with a Mini cylinder. I thought it was on a par with other clutches. Of course it will take more pedal travel to disengage, so could be more vulnerable in that respect - it'll help if there's no excess slack in the clevis pins etc. fitting a braided hose should also help a bit & possibly a residual pressure valve - as long as the release bearing... releases, if you get my drift.

 

Not 100% sure, but I think the MGF could use the same cylinder.

 

..oh and it also takes a M10x1 union.

 

 

While I'm brain farting: a 2 inch diameter wastegate actuator could produce about 30lbs of force from manifold vacuum.

[Ethel]

 

 

Metros had a 5/8" master compared to 3/4" on a Mini. I've used one with a Pre-Verto & pre '76 pedal box.

Thanks for the information. My engine is (was) a Metro 1275, so should be an easy swap. They are fairly hard to find but I did find a NOS one out of Cypress, of all places. Did it make a noticeable difference in pedal pressure?

 

 

It should make the pedal about 12% lighter - if that's any help.

BUT

 

Before going down this road, just be sure you have enough pedal over-travel now or you might find you can't completely disengage the clutch. 

 

I thought more

 

5/8 is 16mm 3/4 is 19mm (ish)

 

πr² > 8x8 = 64, 10 x10 = 100, so roughly a third less area = 2/3rds the force but 1.5 times the distance.

[croc7]

[quote name="Ethel" post="3717160" timestamp="Lll

I have to admit I can't say how much lighter because I never tried it (grey diaphragm) with a Mini cylinder. I thought it was on a par with other clutches. Of course it will take more pedal travel to disengage, so could be more vulnerable in that respect - it'll help if there's no excess slack in the clevis pins etc. fitting a braided hose should also help a bit & possibly a residual pressure valve - as long as the release bearing... releases, if you get my drift.

Not 100% sure, but I think the MGF could use the same cylinder.

..oh and it also takes a M10x1 union.


While I'm brain farting: a 2 inch diameter wastegate actuator could produce about 30lbs of force from manifold vacuum.[/quote]

M10x1 union? Where? Into the MC. If so, I might be in trouble….

Edited by croc7, 03 April 2022 - 12:19 AM.

[Ethel]

M10x1 union? Where? Into the MC. If so, I might be in trouble….

 

Actually, I got that wrong...

 

 

It isn't 10x1, it's 12x1!

 

 

Probably simplest to make up a pipe. You can get the unions on fleabay, or an adapter to 10x1, or a banjo. 

 

Forgot I sleeved mine to use one of Minispares' braided hoses with banjos.

 

 

 

 

...also did some internet digging & found the same part number for the MGF repair kit, so they likely are the same. 

[mini13]

Interesting thought!

 

While I'm brain farting: a 2 inch diameter wastegate actuator could produce about 30lbs of force from manifold vacuum.

 

[Ethel]

...you'd have to invert the push to pull, but there's  plenty of cheap spangly ones on Fleabay.

[mini13]

Well, i did have a vac one off of a VNT, but to be honest i think the stroke might be a bit short on an turbo actuator, but i think Ive got an old air ram lurking.... something like in the link. would be easy to couple in with a rose joint etc etc...

 

https://www.ebay.co....kp:BFBM4LPKwf5f

 

[Ethel]

I was thinking the other way, that a ram could be too long. You can sort that out with leverage though - the link looks good , if pricey, the extruded cylinder could be cut  to size - as long as you can get it to seal.