Hey guys! I'm new here, so forgive me if this isn't the right area to post this thread. So, here's the deal; I bought a 170k mile RX7 for $750. You may think that's a good price but I probably actually overpaid a little. This thing is rough. Here is the rundown on my FC:
-1989 Mazda RX-7 FC3S GTU (S5)
- No compression on the front rotor
- I have no clue about the history of the car (previous owners, maintenence, how it was driven,
- The wiring harness is modified to run a large amplifier and stereo, but there's a switch inside that I think may be a killswitch
- The oil cooler is caked in a black-hairy sludge
- The interior is in dreadful condition aside from the carpeting and headliner
- There are signs of a collision (bondo near back bumper, radiator support brackets are bent)

I suspect if someone bought this car to part it out, the only thing worth keeping would be the exhaust and suspension. With this in mind, I have some questions:
1. The interior of this car is rough and it bugs me even more than the lack of compression. I've found the majority of parts that I'd need to restore the interior, however, I cannot find a dashboard. Where are some places besides eBay and craigslist that may have the dashboard? Are there any aftermarket solutions?
2. The engine cranks, but does not start. But it does backfire while cranking. Is the one rotor with compression the culprit?
3. Since the front rotor makes 0 compression, what are the chances that my housing is damaged? Could it just be the apex seals?
4. The oil cooler is completely caked in a grease and hair sludge. It's about a centimeter thick and it's only on the front side of the oil cooler. Surprisingly, this car doesn't have any oil leaks (at least none that leak without oil pressure), so I'll take any guesses as to what could've caused this. If the car ran while the oil cooler was clogged in such an extreme way, could it be the reason that the engine doesn't make compression?

Thanks for any input, answers, or thoughts. I know I shouldn't have bought this problem but I couldn't let it get junked.

 

1. it was driven like it was stolen since it was new, they all were. its really rare for some reason that people kept records with these, i've seen it, but its the exception.
2. there is probably a small leak at the cooler, and the oil is attracting dust/dirt, for ~20 years. scrape it off, and see what you're dealing with
3. dash is used only. its getting hard to find one that isn't bad
4. oil cooler isn't clogged, and would have no effect on the engine running
5. to see if there is engine damage it needs to come apart.