What would everybody consider to be the ideal temperatures for their water, oil, transmission and differential fluids during track day sessions?

My FD is in the process of getting built with track days in mind. We're running temperature sensors for each of the above fluids that the motec M1 ecu will log and use for safety parameters. I'll be adding in coolers and pumps for the trans and diff at a later date, for now I'll be monitoring them through my dash display.

I'm building my dash display layout to only display critical values in an easy to read manner. I want to be able to easily identify being in a good range at a glance. As a result I'll be making non-linear dials that hold the "ideal" temp horizontal.

My reason for asking is selfish, but I think this info could be useful for others looking to get into track days as well.

 

I tried to compile something similar and came up with... (did not find gearbox temps)

Fuel Pressure: 30 psi at idle to 40+ psi at boost (at ~1 psi fuel per 1 psi boost)
Oil Pressure: 20-40 psi at idle to 110 PSI max (Racing Beat)
Oil Temp: NTE 205F/96C (Racing Beat)
Water Temp: 200F/95C-225F/108C (https://www.rx7club.com/3rd-generati...thread-571088/)
IAT: 100F/38C-110/43C
EGT: 930F/500C-1200F/650C

I like to keep oil and water below 200 if possible. Over 210, i'll come off throttle or pit depending on how hot the temps are. Problem is trying to monitor the health of your vehicle while driving at speed. Best is to have a couple lights for critical readings (no more than 2-3), then log the rest (read between sessions)

 

Right on, thanks Tom.

I think I'll talk to the folks out at liberty gears regarding the trans temperatures, and worst case I'll just determine average differential temps through logging.

Yeah, I certainly agree with the approach of only viewing a few things, but logging EVERYTHING!!

Knowing my ideal temps along with too hot or too cold will help with writing the safety precautions though. I'd much rather have the ECU throw me into limp mode, cutting max revs and throttle opening the moment a danger condition is met instead of hoping that I'll notice something being funky in time...

 

The only thing that looks out of the ordinary is the EGT values. Just cruising the 13BREW makes values of 1400-1500F depending on tune and usually hit 1700F or more after a pull on 91 E10 of course.
Would those values happen to be based on E85 or another alcohol based fuel?

 

I think you are right (can't recall the source of those numbers). That said, i think i warped my seals due to high EGTs, but unfortunately i have no EGT probe to verify

 

Yeah, a more modern ECU can do all the engine management for you. PFC may be a good ECU for driving around town and the occasional spirited drive, but i think you are somewhat playing with fire (literally) using it on a dedicated track car

 

On my 400rwhp FC I monitored EGTs at the exhaust port and it was just over 1,000C at lean cruise and 700C at WOT and would creep to 800C running WOT for extended periods.

Tune was 16-15:1 AFR cruise, 11s at moderate load and 10s to 9s WOT high RPM.

Oil temps usually stayed under 100C hillclimbing in the heat and never went over 110C.

 

Dual 19+ ducted oil coolers really makes a difference. If air temps are below 60, i have to cover one of them (they are currently in series)

 

Coolant Temp = 110c is the danger zone, anything over this is dangerous. if you catch it at 110c there is about a 95% chance the engine is ok, but over this, it becomes a gamble
Oil Temp. its kind of linked in the rotary, you want higher than 80c but lower than 125c (oil can go higher).
Trans Temp, not sure, but the oil usually wants somewhere between 80-130c
Diff Temp, same as the trans.

Intake Air Temp, ideally under 50c, if it goes over (it probably will), then tune accordingly.
EGT: it depends, on where the probe is, but best power is usually 920-950c (Blue T2's tune is not typical), stock seals are ok to 1100c, but usually the turbo is only ok to 900-950c
RPM limit, Stock seals can go to 9500 with no trouble, i've seen dyno charts higher. if you have a soft rev limiter, or a way to lower power its better than a traditional rev limiter. its ok to hit a traditional style limiter, but any real time on it can break stuff

having built a lot of race cars, i can tell you that the driver doesn't look at the gauges, and if they do they don't really trust them very much. it is better to build the car so it works without gauges, with as few as possible

 

Right on, thanks

Yeah I think I'll program the EWP to keep water temps in the 85c - 95c range. Ideally the oil temps will stay in check with the dual 25-row setrab coolers.

Transmission wise, I'm adding an oil bar and ports/provisions for a cooler while Liberty is in there rebuilding everything. The diff will also be getting cooler/pump ports added to the Greddy cover. I'll be brand new to track days with the car, so I dont expect I'll be pushing things too hard for a season or two, that should allow time for the coolers to get added as needed.

I'm using the Gleaseman/Roiel engine flanges with the EGT and e-map ports built into the engine flanges themselves, so I'll be getting my readings as close as possible without being inside the housing.

I started tracking my Aprilia last year and I quickly found that less is certainly more when it comes to gauge inputs!! Thankfully I've gone hog wild on sensor inputs and everything will be calibrated/logged in both my ECU and dash display.

I plan on having RPM on primary display with speed being secondary. Ideally I'll have four minor "gauges" as satelites to the central tech: Boost and oil pressure on upper left and right, then oil/coolant on the bottom left and trans/diff on the bottom right. I need to play with the motec display creator software still to get the temp gauges the way I want them..

I definitely appreciate the shared knowledge to help get my starting point!!

 

Can you share what you are doing for diff and tranny cooling? I need to set one up on an RX8 race car but have never done this before.
Also, why use the Gleaseman/Roiel engine flanges?

 

At this stage we're just drilling holes in the trans case / diff cover and welding on male fittings for the in/out. Those will be capped and probably safety wired to ensure they don't come loose. I should be driving back to California to pick the car up in the late spring to early summer time frame. I'll be able to get installed pics at that point.

When it comes time to add the coolers themselves we'll probably mount them on or near the subframe with ducting to direct air through them. My thought was to fashion some flat bottom underbody panels and have an NACA duct upstream of the cores with them being mounted at an approx 45° angle, similar to a radiator in vmic configuration, with the a flat bottom creating a bit of a vacuum after the cores.

The pump and fan setup could either be PWM controlled or tied to a thermostat trigger if I remember correctly.

This build has already exhausted my budget so we're just adding provisions for the coolers at this time. Unfortunately I can't speak intelligently on brands for the pump, cooler or fans yet since we aren't going there yet. We'll be running -6 lines when the time comes to add them in.

They struck me as a quality product and the CNC shaping made it easier for the shop to fab the manifold piping up. It was basically either them or flanges from burns.

 

Contact Smokey or Pete. Believe they have both installed diff/trans coolers

https://www.rx7club.com/build-thread...1108119/page4/

 

So I'm not entirely sure if I did a good job of verbally explaining what I wanted to do with my diff/trans coolers. I've attached the little sketch I made a while back that shows my general thought process on my ideal mounting solution.

 

So I definitely appreciate everybody weighing in!! I sat down today and made some updates to what I plan on running. I figure I'd share what I have currently for input and suggestions.




Of note, every sensor I'm running will be routed through my ECU first and logged, so I'm not as concerned about displaying items like EGT's, eMAP, IAT, IDC, Water/Meth flow, etc., since all that will be available when I pull the logs. I may add in a small display with the pre-turbo (ambient) intake temp and the split from that to the UIM sensor though. Something like "85 f (+30)" though that may start to clutter things.

 

for your duct read this, https://www.linkedin.com/pulse/air-d...cle-card_title

its a good article, probably got the link from here somewhere

 

That was a good read, thanks for sharing!!

 

Great thread! ??

I'm planning for oil/diff cooling on my car as well. Likely order a couple of these:
http://www.turbowerx.com/Scavenge_Pu...10/page10.html

If you're using a PDM you can tap your pan/cover for a temp sensor and control pump/fan speed based on oil temp.

The Built 2 Apex pans are really nice and pre-tapped, but kinda pricey.

 

I'm running a PDM30 along with my M150 and C127 dash. The shop has already tapped the transmission for the temp sensor along with both ports.

B2A has very nice looking renderings! However, as you've noted, they're quite pricy a d they don't seem to have the best track record when it comes to actually delivering products. I'm passing on them for the time being.


Also, I made some tweaks to my display based on feedback I got from other motec users.


The temp gauges should be easier to read now. I think I'll add another bar graph on the bottom right side, not sure what of though..

 

I have a fully ducted vmount, dual 25 row oil coolers. 20w50 oil, usually see 70-120psi on track. hot summer days 90F+ water temps will get up to 230F. EGTs, i just have a single post-turbo sensor, will get up to 1700-1800. I did warp my apex seals once, what did it was accidentally unplugging the TPS, i think extra fuel from disabled fuel cut made egts go crazy, warped my turbo manifold and lost some compression. funny thing is, compression came back after a few months..