Brakes locking up?
 

I have been having a problem with the brakes engaging themselves on my SVX. The car would all of a sudden lock the brakes up itself and the brake pedal would feel very stiff, if you pumped the pedal a few times the brakes would release. I thought this was a bad caliper, so I replaced all 4(I found 2 bad ones), but the problem is still persistent. My SVX has a 5 speed swap and I was told that I need to shorten the rod on the master cylinder, but I don’t see how that would cause a intermittent problem like this. Any ideas?

I don't remember who it was, and I don't remember the exact cause, but I do remember that someone else who did the manual swap had an issue like this. What was happening is that something relating to the conversion caused the brakes to be "on" a little bit all the time. After driving around for a while the brakes would get hot enough to expand the brake fluid and engage the brakes more. Once it could sit and cool, they could drive again for a little bit.

Sorry I can't be of more help, but maybe someone else remembers more details???

Brake problem.
 

Yes it is as Dave says. The cause of it is the push rod on the brake booster is too long, and not allowing the Master cylinder to return fully. When the brakes heat up the expanding fluid can't flow back to the M/C reservoir so it just builds up pressure in the brake lines to apply the brakes.
You need to shorten the length of the push rod.

Harvey.,