Firewall hole under master cylinder
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From: Charlotte NC
Firewall hole under master cylinder
On my 69 the master cylinder does not completely cover the hole in the firewall. There is still some opening showing underneath it. Is there supposed to be a block off plate there?
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From: Long Island
From the picture it looks like someone enlarged the hole for an aftermarket power / master cylinder.
There is not much room between the master cylinder and the hood, thus an aftermarket / specialty set up may need to be dropped to clear the hood.
There is not much room between the master cylinder and the hood, thus an aftermarket / specialty set up may need to be dropped to clear the hood.
Last edited by BLUE1972; Oct 29, 2017 at 07:25 PM.
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If you are installing NON power master cykinder you could fiberglass over the lower hole. If you are installing power brakes you will use the hole for rod alignment to brake pedal arm.....I think. 
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Mount your brake system and close off the remaining hole. Be sure to check hood clearance if aftermarket.
The hole shuld look like the shown pictures, unless you are using an aftermarket system.
An open hole will allow engine heat into the passenger compartment making driving unpleasant..
The hole shuld look like the shown pictures, unless you are using an aftermarket system.
An open hole will allow engine heat into the passenger compartment making driving unpleasant..
Last edited by BLUE1972; Oct 30, 2017 at 04:55 PM.