Trouble with water temp
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honestly i dont really see it being a waste of money. this car when i bought it was very run down. so ive done new suspension, rebuilt the motor, it has now a koyo rad and now it will have the fans and thermo and also it has the hard rubber lines. and the fans are programed to turn on sooner. after the tray im done spending money on this thing. i still need to finish my firstgen rx7 lol
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From: Bournemouth
One thing to remember is that fans on track at track speeds probably aren't helping anything. If they're coming on when on track you probably have another issue. Fans are really used for 0-30mph to help pull in air and aid cooling. Above this speed the ram air affect is meant to take over and naturally cool things down.
Water Foul
Joined: May 2013
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From: Republic of Texas
Yep. Especially a $60 one.
One thing to remember is that fans on track at track speeds probably aren't helping anything. If they're coming on when on track you probably have another issue. Fans are really used for 0-30mph to help pull in air and aid cooling. Above this speed the ram air affect is meant to take over and naturally cool things down.
True to a point, but it depends on the particular fan setup and how the shroud is designed. There is a thread on here somewhere, wherein I tested running both fans on low vs. no fans driving up to 60mph in the heat of a Texas summer. Surprisingly, the fans helped with cooling up to about 55mph--nearly double your theoretical number. I would try to find it, but photo storage was not durable back then, so my charts and graphs would be missing.
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From: Bournemouth
Yep. Especially a $60 one.
True to a point, but it depends on the particular fan setup and how the shroud is designed. There is a thread on here somewhere, wherein I tested running both fans on low vs. no fans driving up to 60mph in the heat of a Texas summer. Surprisingly, the fans helped with cooling up to about 55mph--nearly double your theoretical number. I would try to find it, but photo storage was not durable back then, so my charts and graphs would be missing.
True to a point, but it depends on the particular fan setup and how the shroud is designed. There is a thread on here somewhere, wherein I tested running both fans on low vs. no fans driving up to 60mph in the heat of a Texas summer. Surprisingly, the fans helped with cooling up to about 55mph--nearly double your theoretical number. I would try to find it, but photo storage was not durable back then, so my charts and graphs would be missing.
What am I doing here?
Joined: Mar 2006
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From: 2017 Miata RF Launch Edition
Pretty much.
Always fix what you know to be broken FIRST. If that doesn't solve the issue(s) you are seeing, then start troubleshooting and replacing/upgrading parts.
Always fix what you know to be broken FIRST. If that doesn't solve the issue(s) you are seeing, then start troubleshooting and replacing/upgrading parts.
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From: Bournemouth
Not sure if you have but it may be worth putting the seal back at the rear of the bonnet (hood). The reason it is there is due to the low pressure zone that is present at speed due to the boundary layer as the air rushes up the windscreen.
Many people beleive that if you remove the seal air will be sucked out. It’s actually likely to be the opposite. In fact many cars have the intake in that area for the outside Air part of the HVAC.... they wouldn’t do that if there was a chance air would be sucked out.
if you look at any high performance production car or many race cars, all of the hood venting is at the front of the bonnet. GT500 is just one example but you’ll find a ton more.
Many people beleive that if you remove the seal air will be sucked out. It’s actually likely to be the opposite. In fact many cars have the intake in that area for the outside Air part of the HVAC.... they wouldn’t do that if there was a chance air would be sucked out.
if you look at any high performance production car or many race cars, all of the hood venting is at the front of the bonnet. GT500 is just one example but you’ll find a ton more.
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From: Bournemouth
Here’s a good write up and theory behind cooling ducting if you have to go down that route (but as others have said it’s probably another issue):https://nasaspeed.news/tech/engine/r...ic-principles/
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From: Champaign, IL
I though I'd update my progress on cooling. Water temps are lower lately, but there's still some room for improvement. I saw 215-220 on track on Monday at Autobahn. If I cruise around at 90%, temps are around 200. Once I really get on it and spend more time at high RPMs, temps go up. If I back off, it'll drop 10-15 degrees within a few corners.
I think the pump is just churning at high speeds. So I bought an S2 pump to put in. Hopefully I can get that done before I go to Mid-O in two weeks.
I think the pump is just churning at high speeds. So I bought an S2 pump to put in. Hopefully I can get that done before I go to Mid-O in two weeks.
I'm sure the fact that the engine makes more power at higher rpm has something to do with it !
I would add : if you are seeing 220 on an aftermarket gauge (think i saw you mention this earlier) that reads 10-15 degrees higher than the stock sensor ...you are probably running at the optimal temp already .
I would add : if you are seeing 220 on an aftermarket gauge (think i saw you mention this earlier) that reads 10-15 degrees higher than the stock sensor ...you are probably running at the optimal temp already .
Last edited by Brettus; Aug 11, 2018 at 06:17 PM.
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From: Champaign, IL
What am I doing here?
Joined: Mar 2006
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From: 2017 Miata RF Launch Edition
After a 20 minute session on Autobahn South, my coolant drops to ~185°F in under half a lap. My oil temps drop to the 190°F in roughly the same time frame.
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Thread Starter
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From: Champaign, IL
I feel like something has to be wrong, here. I just have no idea what it is. I've literally replaced the entire cooling system, except for hoses.
The S2 water pump didn't help at all. Saturday the car was cooler and rarely hit 215, but ambient was relatively low, in the 70s. I had 215-220 in the warmer temps on Sunday.
Water Foul
Joined: May 2013
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From: Republic of Texas
^ I have just re-read all of your posts. According to what you have done, you should be running cool as a cucumber! I have 2 thoughts and am otherwise stumped:
1. Are you absolutely sure you have ALL the air bled from the system? Run the engine up to temperature with the front on jackstands and the coolant bottle cap off. Massage the top radiator hose after the thermostat starts to open to force air out. This might take up to 1 hour. (Some people cut the jiggly thing out of the thermostat on track cars. This helps bleed the system at the expense of taking longer to reach operating temp, but that might actually help you while sitting in the grid.)
2. If you removed the rear hood gasket, that could have created problems for you. That is a positive pressure area where air is forced in from the base of the windshield. It could be working against your hood vents. Where are your hood vents located? They have to be in the right locations to work.
1. Are you absolutely sure you have ALL the air bled from the system? Run the engine up to temperature with the front on jackstands and the coolant bottle cap off. Massage the top radiator hose after the thermostat starts to open to force air out. This might take up to 1 hour. (Some people cut the jiggly thing out of the thermostat on track cars. This helps bleed the system at the expense of taking longer to reach operating temp, but that might actually help you while sitting in the grid.)
2. If you removed the rear hood gasket, that could have created problems for you. That is a positive pressure area where air is forced in from the base of the windshield. It could be working against your hood vents. Where are your hood vents located? They have to be in the right locations to work.
