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I'm fairly confident my 1981 started as a GS with drums, had rear discs swapped in, and currently has 1979 front and rear brakes (long story).
I'm trying to determine what year the master cylinder is, to figure out if some of the less than stellar brake performance in Autocross is due to mismatched parts.
The master cylinder:
The reservoir cap is offset to the back, the proportioning valve is mounted to the MC, and there's an "F" stamped on the front.
Based on the proportioning valve location, and the lack of adapters on the lines, I suspect it is a 1979 MC like the brakes. The biggest concern I have is the "F" stamped on the front. All reference pictures I can find for RX7 MC's have an "R" stamped there.
The brake lines are all routed according to the factory parts diagrams. I'm just concerned that this MC is from a different model or year, and the configuration of it requires a different brake line routing to work properly (line by the stamp routed to Front, rather than to the Rear).
Has anyone else seen this different Master Cylinder before? What year or model is it from?
Since the 1979 and 1980 have a different thread pitch then the 1981-1985 for the brake lines, I say validate based on that. I THINK the 1979-1980 is coarse thread. You might need to get a known line fitting to validate. Not sure a visual of the threads is enough to tell. My eyes aren't calibrated enough to tell.
Not sure you could tell based on the brake booster or not. The 1979-1980 is pretty small.
Since the 1979 and 1980 have a different thread pitch then the 1981-1985 for the brake lines, I say validate based on that. I THINK the 1979-1980 is coarse thread. You might need to get a known line fitting to validate. Not sure a visual of the threads is enough to tell. My eyes aren't calibrated enough to tell.
Not sure you could tell based on the brake booster or not. The 1979-1980 is pretty small.
The brake booster is large, so it should be a 1981+. The person who swapped the brakes to 1979 did it to get the superior disc brakes on his 1979 SA, so he likely didn't swap the booster because it wouldn't fit.
I suppose the biggest concern is that the MC is from a different model that requires different brake line routing. My only other concern is that the disc brake rear's MC is still on the car, and I'm missing the residual pressure valve needed for drums, but I can verify that using thread pitch gauges on the brake lines.
After digging through a lot of pictures, I finally found a picture of a 1980 with the same F casting. That along with 1 brake line on the right and 2 on the bottom tell me my MC is a 1979-1980.
Love her then leave her, but take it to dinner first.
(heh)STYX MOD EDIT:...but (says Daniel)..I personally I am more of a rear end kind of guy...
I like tight lights and I cannot lie..she honks when she horny,she can't deny...Runnin on Rubber,smokin like a ******..this car gives me a chubby..Pedal to the metal jus' like Superfly...
Last edited by misterstyx69; Mar 4, 2017 at 12:13 AM.
