Just moved to Phoenix where its 110 everyday.
89 rx7 with large street port RB heads and exhaust
Gets hot quickly.
What mixture do I need?
Do I need a electric fan?

 

Id say a 70%water 30% coolant would be best. If the stock clutch fan is working properly theres no need to get an e-fan. For starters, replace the thermostat with an OEM Mazda one.

Do you have your underbelly tray installed?

 

yeah it is installed

 

Try checking the radiator for cold spots... I had this problem a while back and it turned out to be a partially blocked rad.

 

whats the cold spot gonna look like, this was a jersey CAr

 

Its gonna look the same... let the car get up to temp, then pull over and hover your hand over different spots on the radiator feeling for areas of no heat... if theres a cold spot you can actually touch the radiator without getting burned. Cold spot = clogged radiator.

 

thanks man I will check that out for shure

 

Also, doing a full coolant flush and refill wont hurt a bit.

 

I think either the fan clutch is wasted, or you have a clooged radiator.

 

Also replace your thermostat with a Mazda OEM thermostat. If the one in there has been used in colder climates extensively, it may be sticking and not opening fully.

-=Russ=-

 

If the radiator and oil cooler have not been removed in 17 years, you may want to check for crap logged between the radiator and oil cooler. Two years ago, I dropped my front lower cover and used a broken yard stick to prob the space between the oil cooler and the radiator. A ton of leaves, bugs, and dirt fell out. I followed up by blowing out with high capacity air compressor from underneath, above. front and back as much as I could reach.

Another point is the sealing strip at the top. I have seen few 7's with it intact. Mine was absent. I used a strip of black tap used to seal doors. Thats what Mazda used originally. The strip prevents air escaping out the top rather than through the two coolers. Just a thought. Some times the simple things go overlooked.