Had a fun track day today at Thunderhill West. Was told there was an 818 there yesterday.
When I left my house for the 2 hour drive to the track, it was 48 degrees but the day warmed up to a perfect 75ish degrees by the 3rd session. Great time of the year. This track will be 100 degrees in a few months.
During the 4th session, I looked down at the oil temp. 290! Yikes! Most I'd ever seen before was 260. Two separate reputable tuners told me 260-280 max (of course, the cooler the better). I knew I was going to need an oil cooler before summer, but I didn't think in 75 degree weather. I'll be doing an oil change tomorrow (Motul 5-40 that I put in yesterday).
Some oil cooler questions...
Any problem with the oil filter hanging too low with a sandwich plate?
Does the OEM engine coolant oil cooler come off when adding a sandwich plate?
Is there some way to plumb in a cooler other than a sandwich plate?
Where to put the heat exchanger (saw some old threads, but no real answers)?
During the 4th session, I looked down at the oil temp. 290! Yikes! Most I'd ever seen before was 260. Two separate reputable tuners told me 260-280 max (of course, the cooler the better). I knew I was going to need an oil cooler before summer, but I didn't think in 75 degree weather. I'll be doing an oil change tomorrow (Motul 5-40 that I put in yesterday).
Some oil cooler questions...
Any problem with the oil filter hanging too low with a sandwich plate?
Does the OEM engine coolant oil cooler come off when adding a sandwich plate?
The Sandwich plate is thinner than the OEM cooler/warmer that you should remove.
Is there some way to plumb in a cooler other than a sandwich plate?
If you had a dry-sump system you don't need a sandwich plate.
Where to put the heat exchanger (saw some old threads, but no real answers)?
Most used the air coming in the left side vent thru to oil cooler.
Looking for tips on installing an oil cooler.
If you had 280 on oil temps. I suspect coolant temps were also high. Did you happen to look at coolant temps.
I went in a different direction on cooling. I used a radiator rated for a 400 hp V8. Then I used a remote-mounted filter and a liquid/liquid marine oil cooler.
If you end up looking for a liquid/liquid heat exchanger (really a baby tube in shell), Discount Inboard Marine has a good selection of transmission coolers. These units are compact and easy to connect. I am using one as a transmission fluid cooler on my 818.
I haven't been data logging water temp, but will start. The gauge cluster water temp gauge was in the green. What is normal temp? What is go into limp mode max temp?
Take the OEM cooler off - noted.
I recall reading the rear side vents don't flow air as much as it seems they would. At least on a gen 2 front nose, it seems like between one of the front nose side openings and the front wheel splash guard would be an ideal place for the cooler. Of course, need to run the hoses. Is there some reason it isn't a common place to put a cooler?
Adding plumbed oil heat to the cockpit would be problematic. That kept me from suggesting my fix to a rotary RX7 rest-rod I built. I started with a SBC/SBF Griffin rafiator for short track racing. I modified it to a two-pass crossflow and welded an engine oil cooler extrusuion into the transfer tank. Oil cooling and water warming was terrific, but the plumbing to the radiator would create radiant heat.
A word of caution, transmission coolers do not handle ICE engine heat adiquately. Transmissions do not develope BTUs like an engine.
jim
I can't figure out a clean (or even a dirty) way to route 2 oil cooler hoses from the front to the rear of the car with my two comfortable functional seats.
Any and all inspirational pictures of oil cooler installations are welcome. Thanks Bob in Cincy for your liquid/liquid pictures and answers.
Dave, Oil coolers have the same challenges as radiators. It comes down to air flow, cross section and thickness.
Most of the heat transfer is done by the leading surface; behind that efficiency drops off. So greater surface area is better than a thick core.
I recently bought a Fiat Abarth. The car is small so cross section in front for cooling is limited. There is a turbo intercooler on either side of the radiator. Complex plumbing but effective.
So my suggestion is an oil cooler core at each side scoop.
Obviously you would plumb in series, so restriction could be an issue and I would test for oil pressure drop across the system.
jim
Dave, Oil coolers have the same challenges as radiators. It comes down to air flow, cross section and thickness.
Most of the heat transfer is done by the leading surface; behind that efficiency drops off. So greater surface area is better than a thick core.
I recently bought a Fiat Abarth. The car is small so cross section in front for cooling is limited. There is a turbo intercooler on either side of the radiator. Complex plumbing but effective.
So my suggestion is an oil cooler core at each side scoop.
Obviously you would plumb in series, so restriction could be an issue and I would test for oil pressure drop across the system.
jim
Hobby Racer explored ducting the side scoops for his AWIC. He has enlarged side scoops and I am not certain what the results were but I "think" airflow was not great.
You could measure for dynamic airflow but it would be so small you would have to have a very low pressure instrument, or monometer to measure inches of water.
If you mount the cooler(s) in the engine compartment you should duct the cooler exhaust outside the body.
Jim Hall created downforce (suction) with a snowmobile engine in the Chapperal "sucker" Can Am car. Like a radiator fan, a sucker would work better than a blower.
My Toyota MR2 intercooler gets by with a fan sucking through the core in the side scoop.
You could create a snorkle pod like the radiator on a P51 Mustang aircraft, snorkle scoop in front, cooler in the middle, sucker fan in back.
jim
I have been trying to plan out where I am going to put an oil cooler in my 818R. At first the best place is up front to get the best oncoming airflow, but the challenge I think is routing the lines back to the engine. These would be long runs, requires more oil, and I am already maxed out with the radiator and AWIC lines going through the small side opening just behind the front wheels. At this point I think a ducted cooler in the left rear side pod or ducted to the rear are the best spots I think. I am holding off until I have the body and wheel well liners installed to see what the clearance is. I do plan to enlarge the side pod vents like Hobby did and I have been thinking about adding scoops as well. I saw you posted in a thread asking if these could be made which would be awesome! Looking at the different mid-engine sports cars and race cars adding on scoops with enlarged cutouts would help to pull in more air to help with engine bay cooling and other ducting to the intake, oil cooler, trans cooler, etc.
Here is what Chad came up with a few years back side scoop ducted to a rear mounted cooler, but I would confirm with Rob T to see what he uses now on his car. At one point in the build thread I think he looked at front mounted cooler https://thefactoryfiveforum.com/show...ghlight=Plavan
The trunk lid opening looks like a good place for an oil cooler. My read of the yarn wind tunnel (about 75 mph) is it's all high pressure outside the hole and low pressure inside - air being sucked into the engine compartment. No apparent wind shear across the hole so a scoop won't add anything.
My oil cooling system is separate from the engine coolant system. I modified the side vents and plumbed in 2 KTM motorcycle radiators, a Bosch circulation pump, and a 3 gallon reserve tank. Included is a flow switch in case of pump failure. The same system also cools my turbo and wastegate. I ran 3/4”lines for the system
I saw my name above and thought I'd comment on what I have, not based on science, but seems to make some sense. As a note, I have been struggling to get my oil above 180F on the track during 80F days with this set up. In order after leaving the dry sump scavenge pump: -12 lines running through a finned cooler seal mounted in the left scoop. It does duct into the engine bay, which is no where close to sealed. From there it goes to the back of the car into a sucking fan unit mounted high in the rear bumper area. That unit has two flexible lines that are plumbed to the right side scoop. Those two hoses just wire tied into the back of that scoop. The fans on the sucker unit are thermostatically controlled at around 190F. From there the oil goes to the spintric and into the tank, which holds about 8 quarts of oil total. Keep in mind, that with the dry sump scavenge system the discharge of the scavenge pump is foamy, and moves in slugs, so not the most efficient from a heat exchange perspective. What I have is likely over kill, and was developed before Gator figured out the 1/2 stage additional scavenge pump solution, but I have zero issues with oil temp, at any time.
Forgot to mention that I’m still using the factory oil/water heat exchanger that the oil filter screws on to. The one that others refer to as an oil heater. Whatever, but if you uncouple that cooling circuit from the engine coolant, you’ve lost 180 degrees from your cooling circuit.
My oil cooling system is separate from the engine coolant system. I modified the side vents and plumbed in 2 KTM motorcycle radiators, a Bosch circulation pump, and a 3 gallon reserve tank. Included is a flow switch in case of pump failure. The same system also cools my turbo and wastegate. I ran 3/4”lines for the system
Lance, please explain. How much oil do you use in a three gallon reserve tank?
How does a flow switch compensate for a pump failure?
I assume that other system fittings and passages are less than 3/4" cross section?
" if you uncouple that cooling circuit from the engine coolant, you’ve lost 180 degrees from your cooling circuit." Do you mean that uncoupling the hot oil from the coolant, the heat load to the cooling system is reduced?
I have found that oil and coolant temperatures rise and fall together and a compatible system is possible, and efficient.
Actually a rear mounted water to oil heat exchanger is a viable concept. Your reserve tank could do that?
jim
Jr, my oil cooling circuit is a water-to-oil heat exchanger. I’m running cool water through my heat exchanger. The 3 gallon reservoir is for my cooling water. The side radiators serve to cool the water as it passes back into the reservoir. The oil is still contained within the engine, it just passes thru the heat exchanger to drop temperature.
The trunk lid opening looks like a good place for an oil cooler. My read of the yarn wind tunnel (about 75 mph) is it's all high pressure outside the hole and low pressure inside - air being sucked into the engine compartment. No apparent wind shear across the hole so a scoop won't add anything.
"Good Judgement comes from Experience. Experience comes from Bad Judgement"
Owner: Colonel Red Racing
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818R ICSCC SPM
2005 Subaru STI Race Car ICSCC ST and SPM
Palatov DP4 - ICSCC Sports Racer
Is that blowing air out of the engine compartment or sucking air in?
Ed Holyoke
It's sucking air in, blowing it down into the engine bay.
Not in these pics but documented in my build thread; there is a second cooler/fan with it's own ducting sucking air thru the tranny cooler and out the back of the car. That was added long after these pics.
"Good Judgement comes from Experience. Experience comes from Bad Judgement"
Owner: Colonel Red Racing
eBAy Store: http://stores.ebay.com/colonelredracing
818R ICSCC SPM
2005 Subaru STI Race Car ICSCC ST and SPM
Palatov DP4 - ICSCC Sports Racer
The oil filter sandwich has a 180 degree thermostat. Each fan has a by-pass switch and a 200 degree thermostat switch on the cold hose.
Street driving: Very hard to get the oil over 210 degrees in our perfect 75 degree California weather. Mostly around 190. And if the fans do kick on, it almost immediately cools to 180 when the fans kick off. I've taken to keeping the fans turned off and blocked the cooler air flow with a piece of card board to get some heat into the oil. Doing so gets the oil up to about 220.
On track: Had a track day at Laguna Seca yesterday. With both fans running, temp never exceeded 230 when the car was actually running 100%. End of session, temp was down to 180 before getting back to my pits. I'm fairly confident I'll be good to go on 100 degree air temp days later in the summer.
"On track: Had a track day at Laguna Seca yesterday. With both fans running, temp never exceeded 230 when the car was actually running 100%. End of session, temp was down to 180 before getting back to my pits. I'm fairly confident I'll be good to go on 100 degree air temp days later in the summer."
That's great news that you have the oil temp issue under control now. I love driving Laguna Seca, it's were I first drove a real race car in the old Skip Barber Formula car driving school. When you get a a oil pressure sensor/data logger I'd love to see your data when launching off the Corkscrew.
Someday I hope we can meet at Thill for a weekend of 818R goodness. It's one of my favorite drives from here.
"Good Judgement comes from Experience. Experience comes from Bad Judgement"
Owner: Colonel Red Racing
eBAy Store: http://stores.ebay.com/colonelredracing
818R ICSCC SPM
2005 Subaru STI Race Car ICSCC ST and SPM
Palatov DP4 - ICSCC Sports Racer
Spent the weekend at Buttonwillow. On Saturday, by the 3rd session it was 106 degrees out and my oil temp touched 290 for just a minute before I noticed. Dialing it back to about 7/10, it came down to 260. Many of the cars left after the 3rd session. It was so hot, I didn't get any lap times or video because my phone was overheated the whole day. It was so hot, the floor of my car started oil canning. It was so hot, I was drinking Gatorade flavors I don't even like.
Sunday was cooler at just 100 degrees and oil temp seemed to max out at 260 without going into limp mode.
Is 260 too hot? Yep, but... I'm using Motul Sport 5-40 oil. I was telling myself that the Motul can take it. I'm sending in a sample for analysis to be sure.
Engine coolant temp stayed cool. I've got a gigantic oil cooler with fans, but oil temp remains the weak link. Nothing more I can really do.
Lessons learned:
1. Stay home if the weather forecast is for over 100 degrees. 100 degree weather seems to be the limit (to keep oil temp below 260).
2. Install an oil temp gauge that can trigger a warning light.
3. Do more research. I'm working under the assumption that 250 is fine. 260 is a strain, but me and the whole car is being strained - it's a race car! 270, slow down and get back to 260. 280 oh ****. 290 be happy the car is still running. Maybe my numbers are high? Or maybe Motul can handle 270+ and still provide 100% performance?
If you are winding it up to 7K or more rpm try "redlining" your car at 6500 and do 95% of your shifts at 6K. See if that makes a difference and let us know your results.
Thanks.
PS: If your oil hit 290 you should change it very soon.
Gator
If you are winding it up to 7K or more rpm try "redlining" your car at 6500 and do 95% of your shifts at 6K. See if that makes a difference and let us know your results.
Thanks.
PS: If your oil hit 290 you should change it very soon.
Gator
It was easy to control the oil temp with the gas pedal. I found if I took it easy on the straights as if I were trying to save gas by accelerating without mashing the gas pedal and shifting as you suggest, I could still go hard in the corners, stay cool and still have fun (except for when a GT3 passed me and I couldn't resist riding his bumper for a lap).
That 290 snuck up on me! An Auto Meter Spek-Pro oil temp gauge with it's configurable warning output feature and a big bright dash light in my face has been ordered. Constantly monitoring the gauge was distracting.
There were 3 STI drivers I was hanging out with that all had heat related issues and auto parts store oil. I told them the same thing - change your oil!
I'm having a sample of my Motul oil analyzed before I do an oil change. Very curious to scientifically know how it held up. Maybe it's okay - we'll see.
Got my Blackstone lab oil report back. It stated, "The oil held up well to the temps you noted. The viscosity is normal and the 5.5 TBN shows active additives left." Seems the oil held up.
Some of the metal levels were a bit high which is concerning. They said to drive 2,000 miles on new oil and retest for comparison.
That oil temp snuck up on me because of the poor placement of my oil temp gauge down low on my center console which requires me to move my head and make an effort to see it. Doesn't seem like a big deal, but on the track, it is. I plan on moving the gauge up to the dash right next to the gauge cluster where it will be in my peripheral vision with a gauge that has a warning light. Even if I'm not constantly monitoring it, my peripheral vision will catch the warning light.
Motul Sport 5-40. Probably don't need for a streetcar, but a must on a track car. I'm not sure a "lesser" auto parts store oil would have held up to my sort of long stretches right at red line and (unintentional) 290 degree abuse.
Another installment of the oil temp saga - hopefully the last...
Moved the oil temp gauge up on the dash where I can easily see it and it has a low and high temp warning light. Also, bigger and easier to read numbers. This should eliminate future extreme temperatures sneaking up on me.
Also rewired the Oil Fan switch to override the thermostat switch to manually start the fans ASAP while still in the pits.
As noted in the post above, my oil survived the constant 270 degrees and 290 degree peak. But, I just discovered the plastic Y fitting at the crankcase vent (part of the PCV system) melted! Easy enough eliminate this part because my system splits the air intake and PCV valve at the air/oil separator.
While I had the dash apart, I added a new low oil pressure warning light. Easier to see and much brighter than the OEM gauge cluster light. This will easily catch my peripheral vision whereas the OEM gauge cluster light was dim and out of my peripheral vision. Comes on at 15psi. Even a split-second dip below 15 psi will flash the light. My oil pressure gauge is on the center counsel, so it takes a head movement to read and can't be constantly monitored anyway, so a true low pressure warning light is a must. A review of the oil pressure gauge on video shows no dips in oil pressure. I don't have oil pressure data logging, so I think the best placement for an oil pressure gauge is in view of the video camera. Killer B pan and pick up, Arctangent control plate. After 14 track days, I think the Arctangent plate has proven that a dry sump isn't needed. It's too bad it isn't made any more. With a bit of marketing, I think a ton of them could be sold to the general Subaru community.
Just back from a perfect weather low 70's track weekend at Buttonwillow. Oil temp never exceeded 240.
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Originally Posted by Dave 53
