Water pump cavitation at high RPM?
 

I know I've read about this in the forms before but tried finding it and couldn't.
My car has been over heating the past couple times I have gone on a hard run on a back road (mostly tail of the dragon) for around 7-8 min of hard running the car will start to overheat. Out of the year's I've owned the car and running that road I haven't had it overheat on me but now it seems like it's about almost every time but I have been catching it as soon as it start's to move then just slowing down and then it cools off, I have been getting faster and harder on the car so that's why I'm thinking I'm seeing it start to show it's self now. I do have an upgraded thicker aluminum rad in the car, only thing done to the coolant system.

Some things I have planned to check from reading here to go over are the lower radiator hose must have a steel wire "spring form" inside it to prevent it from collapsing at high RPM I replaced my coolant hose's I don't remember if it had the coil in it or not, Maybe a new thermostatthat opens at lower heat, really need to get a water temp gauge, and of course changing out coolant since it's been a while since I've replaced it.

I think the water cavitation is my big problem right now, I've been looking at pulleys to help with that problem but I was only able to find this one for the rx8 others seemed to be for the rx 7 https://www.rx8performance.com/produ...rmance-pullies has anyone used this pulley with good result's or know's of another pulley that has been know to fix the problem? Or any other advise from people that have had this problem would be great. I don't even think my car would make it 2 laps around a track above 6-7k Rpm the whole lap with out overheating at this point so it's something I really want to get fixed. If anyone track's there car I would also like to know after about how long of super hard running does there car start to get hot/overheat.

when you replaced the radiator did you happen to reapply the foam?
that helps funnel the air appropriately and can have an effect on temps if not there.

new t-stat? If from Mazmart it will open sooner.

do you have an AccessPort? You can monitor coolant temps that way or with other OBD readers

wouldn't waste money on pulleys

Do you have the undertray on there? Really need that.
I wouldn't worry about cavitation unless you're sitting above 8.5k for a long time.

cranial cavitation maybe :)

Tried to keep as much foam as I could. The new rad was bigger then stock and some of it wouldn't fit with out tearing off.

I'll look into the thermostat.

No access port sadly.

I have parts of the under tray my splitter take's up the bottom part but I have the side parts. It doesn't sit above 8.5K long its about 6-7K though 9K full throttle just back to back

I need to remount my splitter so I'll make some wind channel's to maybe help with the air flow to the rad.

if you're allowing the air to escape and not flow freely to the radiator that's most likely the cause of your overheating.

There you go. The under tray bottom piece forces air into the rad rather than under the car.

Like Jedi has said , you need to seal around the radiator . If you look through the front opening at the radiator and can see big gaps ..... then that is where the air will go. Maybe take some pics so we can all point and laugh ....sorry I mean.................. see where the problem is.

hahah it's ok lmao. I'll grab some pic's later if i can. So you guys think the pulleys is a wast of time?
I'm planning on going over the coolant system, flushing, Thermostat, checking the bottom rad hose for the spring and maybe building some ducting on top of my splitter to help push wind thought the rad since the stock ducting isn't going to work for me

Don't waste your time on that stuff. Fix the ducting to the rad, or none of those other things matter.

Why keep the splitter if it invalidates your cooling system?

Makes some nice down force, I don't have the stock under tray anymore, Car still runs fine and doesn't over heat unless you're on it for a while. Maybe thinking about custom making one out of medal that is longer then what it is now and I could add the ducking when doing that, Because I'm planning on making a custom diffuser out of medal

"Don't think car coiuld do 2 laps like this"
"Make some nice downforce though"

You're playing with fire. If the needle is moving, your engine is already over 230F. You will breach a coolant seal like this.

See my previous reply ...

Yea I've heard about it and how the needle doesn't move until its really bad. That's why I'm trying to get it fixed as soon as I can to make sure everything is properly cooled. It's only ever done it twice and both times cooled back down and I made sure it let the car cool all the way off before shut down. No steam and no problems after words.

Alright so after a while I was able to make it to a junk yard to get an under tray and the car I found and the side parts of the tray but the bottom was broken in 1/2 so I was able to make a custom under tray bottom that mounts in the stock location on the sub frame just a little past the rad out of some metal we had around the house and then bolt it up to my splitter where it stop's right before the rad. Never seen the foam around the rad but since my rad is after market it kinda fills in that space. I also had to remount the splitter and ended up removing the light bar I had since it was also stopping a lot of air flow, now it get a slim light bar. Now after some hard running on the tail of the dragon for tougefest I'm glad to report that the overheating had completely gone away.

I swear 90% of the overheating issues with these cars are self inflicted !

Physically and mentally.

Light bar? I think I've heard it all now. :Wconfused

Well since most of the time it is driven is at night to avoid the po po since it's only ever on public roads. So bringing the sun with you to light up the road is vary nice and you can see a lot better and get a better understanding of what might be just off the side of the road and might run out in front of me. Also good protection for the other 5 ish cars that might be making a MTN pass with me so they can know every thing is clear in front of them. But it's primary use is better vision for late night MTN runs. I know it's not the typical thing you would see but it help's in the aspect that i need it. I'm not like no truck butt hurt riding around town with his light bar on