Trouble with water temp
08-31-2018, 09:11 AM
#76
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Thread Starter
^ 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.)
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.)
I tend to 'pump' the lower radiator hose until it's done burping air out. Could there be more? I suppose.Thanks for the advice. I am pretty stumped, too.
09-13-2018, 07:14 PM
#78
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Over the winter I want to build an airdam, flat floor and proper ducting for the radiator and oil coolers. Maybe that will help? I have no idea. If you come up with anything, let me know!
09-14-2018, 07:39 AM
#80
Water Foul
I keep coming back to Mr. Pockets having an obstruction or incorrect pressure differential somewhere. Those are the only things that make sense at this point.
09-14-2018, 07:55 AM
#81
I agree. I will say just taping around my radiator at the track made a huge difference. I also think I had a pin hole leak in my coolant res to tstat housing honestly. I haven't been able to put it back threw the ringer yet. I think with the new radiator undertray and uprights I should be all set. I also bumped my fans down to 185 with my cobb. Not that it really should help that much on the track. The next step would be hood vents. Honestly the singular look to be over kill, but I'm not sure I could make anything nicer
09-15-2018, 09:32 AM
#82
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I’d love to hear any suggestions you guys might have for finding an ‘obstruction or pressure differential.’
That’s not sarcasm. I mean it genuinely.
Also, I have a Cobb AP, but I’ve never gotten it to connect to a PC. It connects to the car and has Cobb tunes on it, but I have no idea what they do. If any of them might lower fan temp, they might be worth using - thought I think hat would likely only help at idle.
That’s not sarcasm. I mean it genuinely.
Also, I have a Cobb AP, but I’ve never gotten it to connect to a PC. It connects to the car and has Cobb tunes on it, but I have no idea what they do. If any of them might lower fan temp, they might be worth using - thought I think hat would likely only help at idle.
09-16-2018, 12:14 PM
#85
So I had to run access tuner in a windows 7 vm with a USB 2.0 hub. It has to be a 2.0 the RX-8 Cobb DOES NOT support going into .3.0 port. I have also not been able to get it to talk to windows 10. If you can send me your map I can at least bump down your fan kick on and send it back. Feel free to pm me.
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09-17-2018, 09:54 AM
#86
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So I had to run access tuner in a windows 7 vm with a USB 2.0 hub. It has to be a 2.0 the RX-8 Cobb DOES NOT support going into .3.0 port. I have also not been able to get it to talk to windows 10. If you can send me your map I can at least bump down your fan kick on and send it back. Feel free to pm me.
09-17-2018, 10:00 AM
#87
Sounds good to me man, Just shoot me a pm and i'll send you my email.
an update for my cooling, got the full lrb uprights on ( previously had just the undertray) and taped up around the rad for a test yesterday. It wasn't super hot out, but doing some hard 3rd gear pulls to redline, slow down and do again for about 10-15mins my temps never got past 205. Before the temp gauge would start to climb after 5-7mins of this ( at the time i never checked the real temps just watching the idiot gauge) So the combo of new radiator, uprights, undertray and forcing as much air as I can into the rad seems to have done it for me. Sadly I don't think i'm going to get any more hot lap days, if any at all this season, but we will see I'm hoping to go to VIR next month if i can swing the time off.
an update for my cooling, got the full lrb uprights on ( previously had just the undertray) and taped up around the rad for a test yesterday. It wasn't super hot out, but doing some hard 3rd gear pulls to redline, slow down and do again for about 10-15mins my temps never got past 205. Before the temp gauge would start to climb after 5-7mins of this ( at the time i never checked the real temps just watching the idiot gauge) So the combo of new radiator, uprights, undertray and forcing as much air as I can into the rad seems to have done it for me. Sadly I don't think i'm going to get any more hot lap days, if any at all this season, but we will see I'm hoping to go to VIR next month if i can swing the time off.
09-17-2018, 10:09 AM
#88
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Thread Starter
Sounds good to me man, Just shoot me a pm and i'll send you my email.
an update for my cooling, got the full lrb uprights on ( previously had just the undertray) and taped up around the rad for a test yesterday. It wasn't super hot out, but doing some hard 3rd gear pulls to redline, slow down and do again for about 10-15mins my temps never got past 205. Before the temp gauge would start to climb after 5-7mins of this ( at the time i never checked the real temps just watching the idiot gauge) So the combo of new radiator, uprights, undertray and forcing as much air as I can into the rad seems to have done it for me. Sadly I don't think i'm going to get any more hot lap days, if any at all this season, but we will see I'm hoping to go to VIR next month if i can swing the time off.
an update for my cooling, got the full lrb uprights on ( previously had just the undertray) and taped up around the rad for a test yesterday. It wasn't super hot out, but doing some hard 3rd gear pulls to redline, slow down and do again for about 10-15mins my temps never got past 205. Before the temp gauge would start to climb after 5-7mins of this ( at the time i never checked the real temps just watching the idiot gauge) So the combo of new radiator, uprights, undertray and forcing as much air as I can into the rad seems to have done it for me. Sadly I don't think i'm going to get any more hot lap days, if any at all this season, but we will see I'm hoping to go to VIR next month if i can swing the time off.
How did you do that with the tray in place? There's so little room to squeeze arms in. And I have screens in the openings.
09-17-2018, 10:21 AM
#89
No screens for me, which helps, and i'm not a super big guy. I just reached in the smiley bumper and kept on taping. Currently one side is open, i don't recall which. Why would you leave one side open?
09-17-2018, 01:06 PM
#90
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Thread Starter
The suggestion was that leaving the right side open allowed more air to flow past the exhaust manifold.
09-17-2018, 01:08 PM
#91
Hmm.... Seems like some testing needs to be done. I could see some benefit perhaps. I need to get some temp probes and do something. Id like to see some data on that. I would lean towards the idea the more air going across the rad the better.
09-18-2018, 08:00 AM
#94
Water Foul
I had data at one time that showed, on my car, in my application, in my climate at least, that leaving the hot side partially open had little to no effect on coolant temps, but did help hold engine bay and transmission tunnel (and presumably transmission) temps down, where these had increased after blocking all 4 sides of the radiator.
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09-18-2018, 08:28 AM
#95
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I think the hypothesis we reached based on your data was that there's diminishing returns as pressure at the nose of the car increases. There ends up being a bubble of high pressure that pushes air around so the amount of air going through stops increasing with car velocity. Leaving the right side open allows air to bypass the radiator but doesn't really decrease the airflow through the radiator because there's still enough air to create that high-pressure bubble at high speed.
Again, just a hypothesis (not even a theory in the non-colloquial sense) but it seems reasonable.
Again, just a hypothesis (not even a theory in the non-colloquial sense) but it seems reasonable.
09-19-2018, 07:35 AM
#96
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You know, I wonder if my temperature problem could have anything to do with tune.
After following sunlight’s advice above to set up a Win7 virtual machine, I was finally able to connect to my Cobb AP. It reminded me that the tune on the car right now is Cobb’s ‘stock-like’ map.
The car uses a ****-ton of fuel - 2-3 gallons for a fifteen-minute session. Do these symptoms (high fuel use and high temps) suggest my tune is just garbage?
It also hit a max of 191hp when dyno-checked at the last event. Ambient temp was...high 80s? That max seemed within reason to me, but maybe it should be a little higher with a free-flowing exhaust and intake?
After following sunlight’s advice above to set up a Win7 virtual machine, I was finally able to connect to my Cobb AP. It reminded me that the tune on the car right now is Cobb’s ‘stock-like’ map.
The car uses a ****-ton of fuel - 2-3 gallons for a fifteen-minute session. Do these symptoms (high fuel use and high temps) suggest my tune is just garbage?
It also hit a max of 191hp when dyno-checked at the last event. Ambient temp was...high 80s? That max seemed within reason to me, but maybe it should be a little higher with a free-flowing exhaust and intake?
09-19-2018, 07:40 AM
#97
Depending on what type of dyno it was, 191 is a good result.
2-3 gallons per 15 minutes sounds about right too. Welcome to rotaries .Also depends how you measured that 2-3 gallons. The fuel level needs a bit of time to settle after vigorous driving. I see about 1/4 tank per 20-25 min session.
I'd certainly go back to stock and uninstall the Cobb just to remove that as a possibile contributor.
2-3 gallons per 15 minutes sounds about right too. Welcome to rotaries
.Also depends how you measured that 2-3 gallons. The fuel level needs a bit of time to settle after vigorous driving. I see about 1/4 tank per 20-25 min session.I'd certainly go back to stock and uninstall the Cobb just to remove that as a possibile contributor.
Last edited by Loki; 09-19-2018 at 07:42 AM.
09-19-2018, 07:47 AM
#98
Sounds about what I use on the track. I need to take fuel out of the tune for sure. But someone can correct me if I'm wrong running rich honesntly should help cool things down if anything
09-19-2018, 07:58 AM
#99
Water Foul
I think the hypothesis we reached based on your data was that there's diminishing returns as pressure at the nose of the car increases. There ends up being a bubble of high pressure that pushes air around so the amount of air going through stops increasing with car velocity. Leaving the right side open allows air to bypass the radiator but doesn't really decrease the airflow through the radiator because there's still enough air to create that high-pressure bubble at high speed.
Again, just a hypothesis (not even a theory in the non-colloquial sense) but it seems reasonable.
Again, just a hypothesis (not even a theory in the non-colloquial sense) but it seems reasonable.
You know, I wonder if my temperature problem could have anything to do with tune.
After following sunlight’s advice above to set up a Win7 virtual machine, I was finally able to connect to my Cobb AP. It reminded me that the tune on the car right now is Cobb’s ‘stock-like’ map.
The car uses a ****-ton of fuel - 2-3 gallons for a fifteen-minute session. Do these symptoms (high fuel use and high temps) suggest my tune is just garbage?
It also hit a max of 191hp when dyno-checked at the last event. Ambient temp was...high 80s? That max seemed within reason to me, but maybe it should be a little higher with a free-flowing exhaust and intake?
After following sunlight’s advice above to set up a Win7 virtual machine, I was finally able to connect to my Cobb AP. It reminded me that the tune on the car right now is Cobb’s ‘stock-like’ map.
The car uses a ****-ton of fuel - 2-3 gallons for a fifteen-minute session. Do these symptoms (high fuel use and high temps) suggest my tune is just garbage?
It also hit a max of 191hp when dyno-checked at the last event. Ambient temp was...high 80s? That max seemed within reason to me, but maybe it should be a little higher with a free-flowing exhaust and intake?
09-19-2018, 08:28 AM
#100
Registered
Thread Starter
Yep. That is it in a nutshell.
My car with stock S2 tune uses ~1/4 tank per 20 minutes on track. These cars make about 200WHP +/- 10WHP when perfectly healthy. 191WHP is within normal range--especially when warm outside and with a few miles on the engine. Be aware that some intakes, even the "good" ones, have the potential to rob power by a few HP.
My car with stock S2 tune uses ~1/4 tank per 20 minutes on track. These cars make about 200WHP +/- 10WHP when perfectly healthy. 191WHP is within normal range--especially when warm outside and with a few miles on the engine. Be aware that some intakes, even the "good" ones, have the potential to rob power by a few HP.
Thanks.