The only places I would expect to see significant deltas are after the cooler(s) (coolest) and inside the engine (hottest). The rest of the circulating oil should be pretty close to the pan temp.

 

Yeah I had it post cooler on the oil filter housing (return) and so no real difference compared to pre cooler in spirited street driving. The only time you will see temps climb are in the upper rev range for extended periods and even the stock coolers do a good job of dropping those temps back down once you let off and get a couple seconds of air thru them.

That depends on the track though, I can see oil temps staying extended on a short track with few straights in high temps. But on a stock street driven car oil cooler modifications are useless as the stock system works great. People should instead focus on using good oil and changing it often.

 

Honestly, I have never paid much attention to my 8's oil temp. I have simply judged it by the condition of the oil. After 1,000 miles of driving to, on, and from the track, it still looks amber. After 3,000 miles of street driving, it still looks amber. It never looks more than a little dirty, so I figure it is not getting hot enough to varnish or start to break down, and all of the Blackstone reports have been good. Based on those indicators, I choose not to worry about it.

 

These oil cooler thermostats are not going to radically change the oil temps throughout the system. Modded FD customers of my rotary wrench found them helpful in an overall modified cooling system, like I now have on my RX8. They are not for everyone, but for the way I drive and use my RX8 they do add a small benefit.

BTW Steve and 9krpmrx8 , I will be moving to Grapevine, TX. by the end of the summer. Look forward to meeting you Texas folks and we can share knowledge, discuss and argue stuff in person. LOL

 

^ Let us know if you notice anything like condensation in your oil. If you use these with no problems at all, I might follow suit. Rotary Performance is pretty close to my office, so I can run over there and pick up a pair at any time.

Welcome to Texas! You're gonna like it here. Nice people, low(er) stress, wide open spaces, and pretty girls. What's not to like? Grapevine is a great area. You will be about 30 mins away from me.

Be forewarned. Once you are here, I will start dragging you to the track. We don't have any 8s out there right now, and we need to remedy that!

 

I will keep the forum informed on how these perform. So far after a couple thousand miles with them installed, no oil condensation.

I am looking forward to the move and hanging with the RX8 crowd there. I have lots of family there also. Yes I have noticed the less stressful lifestyle and the loads of pretty women on my visits there

 

^ BTW, Texas is big enough, that 9K might as well be in Montana, geographically speaking.

 

It sure is, I just spent 5 days off roading in West Texas and covered almost 1000 miles.

 

When it comes to water condensation with cooler oil temps you guys are forgetting how and where water is going to be removed from the oil.

Let's start with what we know.

Water and oil don't mix.
Water boils at 100C.
Water vaporizes more readily at higher temperatures and lower pressures.
The oil pan is at less than ambient pressure.
The oil system is under moderate pressure.
​​​​​
​​​​With the engine running the oil in the pan is pretty well mixed up, so we'll disregard water not evaporating due to being covered in oil. That means that while boiling of the water is ideal it can't be the main way for water to vaporize and that leaves evaporation.

There are two main locations that water will have the chance to hit it's vapor point, the oil pan itself, and the ultra low pressure zone on the bearings. In the bearings there is a significant low pressure zone where any water would flash into steam (regardless of pressure) before being forced back into the oil pan, where it's sucked into the engine. In the oil pan the water will just get slowly evaporated out into the engine.

These little oil temperature changes aren't going to cause water to condense in the oil, because in our engines condensed water is ejected very very quickly.

 

Kudos. I basically did the same thing with an allen bead bolt fitted with an O-ring on it. The thermostat spring shaft on the threaded cap hit the bolt just short of the cap sealing and then cranking the threaded cap to seat itself also seats the O-ring on the bypass blocking bolt.

 

So, to revive this thread...

I have an 09 I just bought with 68k miles. Manual and I bought it as a fun daily, I put quite a bit of miles per day on the car and live near Houston.

I've had an 85 gslse before with a 400 built small block and most recently a demon car 93 fd with a 412 small block with a blower. So this is my first rotary powered car. I have found that all my experience and knowledge about cars comes to be very meaningless in regards to engine references in regards to a rotary.

My main goals for the car are try and get a clean reliable 30k out of it (I promised the wife Id get my moneys worth) and then drop in a built ls motor and t56 (build in progress already). Something mild and reliable. AC and power steering intact.

Meanwhile my thoughts are upgrade cooling and oiling efficiency.

Is the cooler oil thermostats worth while or is a delete a better option? I already have a motorad failsafe thermostat that's a little cooler and evans cooling coolant I was going to put in the motor.

 

Unless you are doing something extreme like track ing in hot temperatures the oil.cooling with the stock coolers is more than adequate.

lots of other things I would worry about first

 

Didn't really plan to change the coolers, just the thermostats to lower oil temps.

 

Still not worth the muck around for little to no gain, the Oil Coolers in S2 were changed slightly as is the cooling system, heat for normal road use is not an issue in S2.

 

OK, guess Ill stick to the failsafe stat and evans cooling as just maintenance

 

Definitely do not delete them. If you do, your oil will never reach operating temp in the winter.

 

Im just going to do the air flow diy to increase efficiency and do the coolant swap to evans and the failsafe thermostat. I think that will be enough for my commute.

 

Just stick with with Mazda green coolant. It's pretty good and don't fix what isn't broken.

Some coolants are known to eat away silicone seals. Mazda green coolant doesn't, but I am not sure if this Evan's coolant will. Seems like it's more designed for hot rods. At normal operating temp, your coolant shouldn't boil anyway, and if your coolant is getting low, there is a little light in the dash that will come on.

https://www.rx8club.com/series-i-tec...licone-238638/

 

I run Evans, it's great.

 

The evans is the best you can get. It wont hurt anything and will run more efficiently.

 

So I assume it doesn't contain 2-EHA?

Can't find any info about that on their website.

 

Whilst I agree with the thrust of your comment, I'm in an awkward frame of mind tonight and want to quibble: my friend has them deleted on his track car and shoves a blanking plate (well, cardboard) in front of the coolers when the weather is really cold.

 

I don't run any oil cooler thermostats and getting up to temp is no problem. But I live in South Texas. It takes about ten minutes to get oil temps above 160F in my Turbo RX8 and it rarely drops below 200F if I am driving as I normally do. That is about the same as it is in my twinscroll Turbo inline 6 335i.

 

Any chance you can tell me what parts I need to delete them, Ive decided to go ahead and do it.

 

I have been using these for around a year and a half.. Still happy with them. I live in Florida, am running a big radiator, and do not see over 200 degrees of engine temp. I see no signs of condensation in the oil. I would like to point back to revival 1 where I boiled a stock thermostat for several minutes and it never moved a bit. The starting to open temp was above 212.