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rlara · Joined: 04 Nov 2005 Posts: 5 Location: Los Angeles

I race a 1st Gen. RX-7 and have a question about the oil cooler. I’m referring to the oil cooler that looks like a little radiator not the one the lives under the oil filter.

The class I race in here in southern California is called Pro-7. We are not allowed many modifications on the 12A. Only blueprinting, an oil pan baffle, and the smaller crank pulley are allowed.

I’ve raced all season with the stock oil cooler with the thermostat removed. Someone told me that removing the thermostat doesn’t force the oil to circulate through the whole cooler. They said some oil does go through the cooler but most of it just circulates back out the exit port. Does anybody know if this is true? My oil temps are around 198F – 210F, so I assume some cooling must be going on.

I blew a motor at my last race and installed a borrowed motor from one of my competitors. We didn’t use my oil cooler because of the potential of metal shavings. We used another oil cooler and that motor ran oil temps as high as 240F for the while race.

The oil cooler from the blown motor is getting ultra sound cleaned, but I want to make sure it runs affectively when I reinstall it back in the car with a new motor.
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Robert

Blake · Posted: Wed Nov 09, 2005 6:49 pm Post subject:

Yes, you need the thermostat in the oil cooler or the oil won't circulate through it; just bypass. It's really easy to check by feeling the cooler in different places on the face. It should be hot evenly. If the oil is not circulating through the tubes, it will only be hot near the end tank. The thermostats rarely go bad.
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Blake Qualley
Pineapple Racing, Inc.
(503) 233-3878

rlara · Joined: 04 Nov 2005 Posts: 5 Location: Los Angeles

Blake. I just spoke to you today about purchasing a motor adaptor for my engine stand. I plan on buildiing a motor for the 2006 season. I talked to Rob on the phone and he had a lot of advice on what type of apex seals to use.

I have more questions if using carbon or steel would be better for my stituation. Rob if he were building a motor based on our rules, he would put steel apex seals as opposed to carbon. He said I could play with the seal spring to tweak. I'm not clear on what he meant. Can I use a different spring than what is recommended by Mazda for an apex seal spring for better sealing?
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Robert