I was wondering how if there is a major difference in engine temperature with dual oil coolers? If their is any, is it possible to adapt dual oil coolers to the the touring 3rd 7's?

Thanks.

 

I don't have numbers on the cooling effect, but it has to help or Mazda wouldn't have added them to their track-oriented R models. The car is lighter and has a lower polar moment without a second cooler, so I don't think they would have added it just for fun. I have heard that 30% of engine cooling on the rotary is from the oil. True? I don't know, but it seems like most or all Mazdas with rotaries have oil coolers as standard equipment.

Crooked Willow Racing sells a kit to replace all the lines, coolers, and ducts. I installed the dual kit on my base model. For info and pics, go here:
http://www.maxcooper.com/rx7/parts_i...lers/index.htm
http://www.crookedwillow.com/

-Max

 

I was wondering about this myself.


chris

 

My thought is that during road racing with long periods of sustained boost adds a dramatic increase in oil temps because the turbos are working really hard. Not doing any road racing? Going to a single turbo? If either answer is yes I would think you might not need the second oil cooler. I have no data to prove this .... only my thoughts. I have an R1 and when I go single, I'm going to a larger single oil cooler and ditching the second one in favor of cold air intake and a lighter car.

 

I have heard numbers from people with the CWC dual coolers supporting a 30% decrease in temps. Most noteably in cooler weather 60-85 deg they noticed a 60 degree temp drop.

 

There was a post a long time ago that Dave from KD Rotary said the dual R1/R2 coolers run about 5-10 degrees cooler than one stock cooler and the CWR set up runs about 25 degrees (F) cooler than a single stock oil cooler. This is all at the track of course. But like I said, it was several months ago, and I really don't remember the details.

But yes, much of the cooling on rotaries is done by the oil and as we all know, the cooler the better. I have the CWR dual oil coolers, and they are nice. The fit & finish are great. The car does take longer to warm up with them now. For me, they're just a little added insurance and peace of mind. They're pricey though.

Too bad no one retrofits a 2nd gen oil cooler for 3rd gens.

 

Check your thermostat on the duals. Should not take a noticable additional time to warm up. At least not to about 160-180 degrees when the thermostat opens for full flow into the coolers.

Al Beder (from the big list) had some issues with CWRs and cooling...not sure if it was thermostat related. I'll search for his post about it, if I can find it.

 

Even if you don't go with dual coolers - make shure the all the fins on the cooler are straight & clean - when i cleaned & streightened mine it made a noticable diff.

unfortunatly I cant add a second eng oil cooler as the cooler for the auto trans lives in that spot

 

Has anybody tried to upgrade the oil cooler from Summit? I have an R1 and was thinking about upgrading the oil coolers to bigger ones. Just curious if someone else has tried it. The Crooked Willow oil coolers are too expensive in my opinion.

 

Earl's are better. Complete dual setup with better fittings, remote located filter and thermo. will run you about $550 without labor. You have build your own hoses. Get a catalog from Earl's. (but no ducts) They are in Cali, but here is the only link I have marked.


Earl's coolers

 

There is additional information on 2nd oil coolers on http://www.scuderiaciriani.com/rx7/oil_cooler.html, including all the part numbers for the stock R1 2nd oil cooler. Seems to be priced pretty well if you get it from Mazda Comp.