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Brakes bled and pedal goes to the floor but I do stop... sort of.
#33
Ok here is the deal with the new MC and the Duff's MC.

Duffs
-------
Bore: 1.090 (slightly less than 1-1/8
Stroke: 1.650
Cylinder Depth: 8.03
Piston Diameter: 0.92

'69 El Dorado (4120)
-------
Bore: 1.131 (slightly more than 1-1/8
Stroke: 1.559
Cylinder Depth: 8.015
Piston Diameter: 1.120

The difference in bore sizes are significant enough to prevent swapping pistons between MCs. Duff's advertises a 1-1/8" bore and the parts store states this new MC is 1-1/8 too but someone or something is wrong here.

Also, the size of the new MC, in terms of capacity, seems larger than the Duff's MC.

The stock bronco rear cylinders are 15/16 and the el dorado rear cylinders are 1". Also the rear drum inside diameters are the same between the two vehicles.
The bronco OD of the front rotor is 298mm and the el dorado OD is 280mm.

Do you think with the larger bore and shorter stroke I can use this new MC or just bite the bullet and get a new one from Duff's?



Here are some pics....
Duff's MC on left
Duff's piston on top

[Image: IMGA0334.jpg]
[Image: IMGA0333.jpg]
'77 351w- Explorer EFI, 4R70W, 4-link, lockers, 4.56, 35" MT/Rs with a severe rock addiction.Confusedmokin:
Roads? Where we're going, we don't need roads.

[Image: sig2.jpg]
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Messages In This Thread
Brakes bled and pedal goes to the floor but I do stop... sort of. - by chuzie - 10-22-2009, 12:24 PM

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