Anyone Know master cylinder bore size?

[Shealey]

I think I found a great deal on a duel master cylinder. I need to know the bore sizes for the bugeye and also later sprite bore sizes. I have some other parts on order now. If I can get a quick answer I may be able to add this to my order today.


TIA

 

[fmichaels]

i believe (don't quote me), that the bore size is 7/8". someone should be along any time now to either refute or back that up!

 

[Shealey]

Thanks, Anyone else? confirm or deny?

 

[drooartz]

7/8" for drum brake setups (Bugeye, early Sprite Mk2 and Midget Mk1). Later disc setups were 3/4".

 

[Shealey]

Thanks, That's what I was looking for. I have a Bug with disc brake conversion.

BTW: I'm purchasing a new duel master cylinder very simaler in appearance to the stock unit.

 

[BWillis]

Shealey,

If you have a disk brake conversion but the original master then you still have a 7/8 bore. It's doubtful that the bore was increased and a later pedal box would be obvious.

HTH,

 

[drooartz]

Ben is right, most folks when they do the conversion just try and make it work with the larger bore. It's been recommended to try and switch to a 3/4" bore if you can find one, or have your master re-sleeved to the smaller size. There is a guy who is trying to have 3/4 pistons manufactured right now, as they're not really available anymore.

 

[Shealey]

Ben,

I found a source for a "stock style" duel master cylinder. I can get it with
bore stroke
5/8"-5/8" 1.5"
3/4"-3/4" 1.4"
3/4"-7/8" 1.6"
7/8"-7/8" 1.7"

The fit is a little tight in the stock pedel box. But the price is around $ 200. vs the Moss price at $ 400.00

If you need to have OEM look this is not for you. But if you are looking for a master cylinder with modern parts this may work well. I'll give you a report when I have it and try it out.

BTW: If I would have checked the Moss online catolog first I would have had the info as they list the two sizes there.

Duh

 

[Trevor Jessie]

Hey I'm interested in this source. Anymore details?

 

[BWillis]

Yes, do post a link.

 

[Bruce_B]

If it fits in the original pedal box...I'm in too!!

 

[regularman]

Allow me to make a suggestion on the pedal boxes. I had had mine off once and sandblasted and painted with rustoleum and went back to using it for almost a year.The spills of brake and clutch fluid and scratches,etc. had it rusty and looking rough again in no time. This time I cleaned it down with a wire wheel and used laquer thinner and cleaned it and put a couple coats of black por-15 on it. That stuff dries shiney and (even though I got a couple runs) looks good and is hard to scratch and brake fluid seems to have no effect on it at all. I would not pull a pedal box off to do it, but if I had it off, I would definitely do it. You can get a pint for $20 or so and a quart for $35 and it goes a long way. Its much thinner than rustoleum but adheres well to anything(even fingers). I bought a quart and it was enough to do my trunk and floorpans and engine bay area and part of the underneath.

 

[jlaird]

Next time around I powder coat mine.

 

[fmichaels]

did someone say powder coat? ... absolutely! have to go, the ovens ready!

 

[jlaird]

LOL, lets see some pics of this work.

 

[spritenut]

Gerard <pixelsmith@gerardsgarage.com>
Is having the 3/4 bore parts made.
Disc brake cars all used a 3/4 bore master
Drum brake cars used a 7/8