My current radiator is good for daily driving, auto-x and all. But last summer, I went to the mountain [wasn't that hot], staying in the high RPM range from 5-7K for about 15-20 mins and the car's temperature started to raise, I realized it at about 3/4 of the bar so I stopped right a way. I popped the hood and there's smoke coming out from the header... but it's fine after it cools down.

It's fine with auto-x... but I am planning to go to track in July so I want to get the car ready for it... do you guys think that this radiator can do the work? Or should I just go to the junkyard and look for an aluminum radiator and custom fit it? If so, any recommendation for which radiatiors to ****** from?

Here is the link for the one I was looking at...

http://rx7.com/store/rx7/saengine_maintenance.html


Thanks,

Mack

 

Mack,
Things I ask before you start replacing parts. Are you running an electric fan or the stock fan clutch. Do you still have the underbelly tray that is under the engine. Have you checked to make sure their is no debri gathered inbetween the front of the radiator?

Also is the current radiator original or ever been cleaned out by a radiator shop?

 

I am running the stock fan clutch, I do not plan on getting the electric fan because from what I heard... it doesn't work as good after 2nd gear. The tray is gone, and there's nothing between the front of the radiator, except my homemade cold air intake's filter. The radiatior was from another member whom I bought it used from, I flushed it myself and cleaned it frequently to make sure it stays clean and all. Maybe I should have it cleaned out by a radiator shop perhaps? Someone told me that our radiator is pretty good already... so yeah...

 

I would verify that the fan clutch has good resistance when attempting to spin it by hand after the engine is at operating temperature.

The lower tray is supposed to aid in cooling. Recommend you reinstall.

Make sure there is no build up of bugs/leaves at the front of the radiator.

I am assuming you have the fan shroud on the car?

When was the last time the T-stat was replaced and are you using the Mazda one or atleast an oem equivelent?

Verify that the fan belt is tight.

How often is the oil being serviced? You should be using a 20W50 in hot climates so that it can dissapate heat better.

If it has been verified that the temp reading you had was accurate and not a malfunctioning gauge or sender.

I would suspect that the radiator may be somewhat restricted and not flowing correctly. It is normal for the temp to rise in hot temps and going uphill but not the mark as you have stated.

The stock radiators in your year vehicle are very adequate. I believe they are a 3 row radiator.
Make sure you are using a 50/50 mixture and I recommend that you put in a bottle of redlines water wetter also.

Forgot to add. Check the condition of the lower radiator hose. Make sure that it has not become soft and possibly starting to collapse when the T-stat opens up to circulate water.

 

Thanks Doc. I will go home and check the resistance when I spin the fan, should be good though cause me and bro looked at it before. The gauges aren't malfunctioning, cause it was only that time that it went up and it was obviously overheating cause there was smoke coming out from the header. I changed the T-stat, forgot was it from Mazda or what but they are OEM equivelent. I believe I got it from MazdaTrix, can't go wrong with them. I will go get some Redline water wetter also, I planned to but I think from what you said... it's probably the radiator being a bit restricted and not flowing correctly... I will probably get those things to flush it again. I know everything works fine in the car, except the radiatior or probably need the underbelly for the car. But how does that help?

The radiator hose in the bottom is good, it's super stiff.

What will 20W50 do to the car? In terms of, performance, etc... I use 10W40 or 10W30 I forgot...

 

"What will 20W50 do to the car? In terms of, performance, etc... I use 10W40 or 10W30 I forgot..."

20w50 is thicker so it helps dissipate heat better than something thinner, like Doc said. In our cars, the oil does a lot of the engine cooling so that is one of the benefits.

As far as the underbelly tray goes, it is vented to help pull in air and works in tandem with the front air dam. It also helps seal off the engine compartment somewhat from road debris, and since its underneath the fan it works with the shroud and helps make the fan's output go towards the engine rather than underneath and around it.

 

Well, you know, maybe that's another question to ask, are you running a fmoc? or the beehive? I'd think the FMOC will work better then the beehive.

 

I have the FMOC... sorry I was gone for the whole week... didn't have a chance to look into it yet but I will let you guys know.