alxltd1

Moved this from the Tech Section: This is for my 2000 MN6 Coupe

Starting to prepare my coupe for some track time, road course specifically. It currently has no engine oil cooler (EOC), power steering cooler, or any transmission or differential coolers. The road courses are all in Florida so ambient heat will be a factor as well. Searching the forum there is a wealth of information but it varies as to specifics. Generally I am looking for some information regarding the following:
• What is the “sweet spot” for engine oil temp?
• How do you calculate the size of the EOC needed (IE: how many rows/passes vs physical dimensions)?
• Where is the preferred location for the EOC (assuming a naturally aspirated engine)?
• What size and where would you locate a power steering fluid cooler?
• Are manual transmission and differential coolers required?
Any input as to specific brand coolers would be greatly appreciated as well. Mocal versus Setrab, any experiences would be appreciated. Stainless Steel braided lines versus Nylon braided lines, again any input appreciated. Currently, from searching this and other forums I am looking at the following:
• EOC being a Setrab 50-613-7612, located directly behind the front license plate cover modified to be open with a mesh screen. Lines to be stainless steel braided -10 AN. Also using the Improved Racing Low Profile Adapter with a 212 degree thermostat.
• Power steering fluid cooler being a Setrab 50-107-7612 directly behind the driver’s side fog light bezel that is modified to be open with a mesh screen. Lines to be stainless steel braided -6 AN. Also using a Turn One pump and pulley and Red Line fluid.
Thanks in advance.

brkntrxn

Here are my recommendations and similar to what I have on my racecar:

- DeWitts direct fit radiator (from Summit)
- Spal electric fan (I have a 17", but a 14" will work just fine)
- Engine oil cooler is in front of the radiator inside the radiator duct
-- pretty much any decent size Setrab or Mocal will do. Mine is huge, from NAPCAR world, but typical size is in the 10"x6" area
- Stainless braided lines for the EOC
- Factory OEM power steering cooler behind the radiator
-- I will probably change this at some point to a stacked Setrab cooler (same location)
- Turn 1 PS pump and rack (upgraded to 1800psi for sticky tires and aero)
- Doug Rippie Motorsports trans cooler
- No diff cooler

The sweet spot for my coolant temps are now 209-213* with engine oil temps ranging from 235-245*.

My advice is to NOT overthink the calculations on heat loads, rows, and passes. A vented hood, a SEALED radiator shroud, and a completely sealed radiator (don't forget the bottom) helps more than people think.


-Kevin

danh52

If you car see's street duty you might want to go with an EOC in the rad tank. This will help with engine warm up but might result with higher peak temps than an air to air cooler. I have coolers on engine, trans and diff with temp senders for each and even with the rad to help warm up the oil it take a while to get up to temp on the street.

alxltd1

Thanks, for the info.

Is this the service that Turn One does on the rack you supply them?

alxltd1

Would not the Improved Racing adapter with a 212 degree thermostat help in getting the oil to warm up on the street?

zrtman1

I use their FSM-215 and oil comes up pretty quick. Running a 72 plate setrab on a LS3 C5. Trans temp on my 6060 was 300F after last 30 min secession at VIR - I am adding a cooler.

Quickshift_C5

What are your temps with the oil cooler, and where did you mount it?

Do you monitor diff temps at all?

brkntrxn

Yes it is, you have to specify you want the 1800psi upgrade.

Scooter70

I'm curious about this too. I have a trans cooler in my C6 Z51 but no diff cooler currently. I'm switching to a C5 diff this winter and was thinking about adding a cooler to it. For 20-30 minute track sessions is the diff cooler overkill?

zrtman1

I mounted it behind front plate. 240 is the max I have seen so far. I can do some ducting to help it out more - right now air can go under/around cooler - it is not at its max efficiency yet. Like everything it is a work in progress.

Not monitoring the rear diff yet, but it does have a 19 row Earls cooler. I clocked the C6Z pump so it fits better on the C5.

I have used a laser gun to check it and it shows low 200's but I do not trust those. I can put a gloved hand on it and feels less hot than the oil cooler. I need to make a fitting or adapter to get the GM temp sensor in one of the diff lines.

Quickshift_C5

Is anyone using the diff and trans coolers from DRM? If so, what are the results?

Mark@AMT Motorsport

I use both. My tranny and diff have been worked by RKT56. We rebuilt the diff when I changed the engine last year and the diff was blown to bits. So we added both coolers. I've had no over temp alarms since we installed them.

argonaut

+1. I have DRM tranny and diff coolers in '99 FRC. Tranny rebuilt by RKT56 with cooler return line located to squirt directly on the gears. Before coolers I burned up a diff and had to replace and Rick said the tranny didn't look to good either. After coolers - no issues (been about 4 years, 50+ track events).

Quickshift_C5

Fantastic, thanks guys!

Is it possible to run those DRM diff/trans pumps off a switch, so you can turn them off on the street? Any negatives to doing that?

alxltd1

Does it make sense, or is it necessary, to wrap the cooler lines in a protective sleeve, especially where their proximity is close to headers or subject to rubbing? I am planning on using steel braided lines covered by nylon, but wondering if an additional sleeve would be wise.

Quickshift_C5

Absolutely makes sense. I've seen others do it, and I plan to do it as well. I can't see any reason NOT to do it.

0Anthony @ LGMotorsports

For the endurance cars we would like to see water temps 180-220 range, and oil temps 240-265 on track. Never had a temp gage on the PS for the cars and we used OEM new racks in all of the cars, including the ALMS car. We did use a larger reservoir and a finned tank for heat with a small cooler. Trans and diff temps are going to depend on what kind of trans it is, and the diff type. It would be nice to see trans temps under 220 and diff around the same.


Now we have always like to try and keep the engine oil cooler inside the radiator for a number or reasons. 1. it helps warm the oil when the car is cold, 2. it is more efficient of a design being fluid to fluid, and 3. it saves on space and extra lines. Not all cars can get away with this setup but most NA cars can.

PS cooler, you can do a couple ways. We have done a couple custom radiator with that in it as well, but most will just mount in front of the cradle or just in front of the radiator. I would run good fluid in it like the RedLine PS fluid you mentioned.

Trans and Diff. We came up with a neat tidy little package for the cars for the challenge cars back in 1999. Lets face it, with everything going on inside the car a lot of people will forget to turn on the electric pumps, plus you have the added load on the electrical system and weight of the pumps hanging out back there. We run the system with a mechanical pump mounted on the diff along with filters and twin setrab coolers all tucked away to keep them safe and the car easy to work on. Doesn't weigh much and as soon as the car is rolling, you are pumping.

0Anthony @ LGMotorsports

oil return with filter



oil cooler



radiator with EOC and PS cooler



lines and fans



heat protection


Most lines I like to wrap if for nothing else it helps keep things safe. For Stainless it keeps the line from vibrating and sawing through something, and for the nylon hoses it keeps them from being cut. The above car is a Daily Dry Sump setup but gives you an idea of what I was talking about above.

alxltd1

Anthony (LG) thanks for the detailed info and pics. Very informative and helpful.

Bill Dearborn

On my C5s I used the DRM Ron Davis Racing Radiator with external oil filter. This was put together before they started using the port above the filter to run the oil cooler lines from. Mine has an adapter that connected to the oil filter mount with the oil filter being relocated to the front of the engine compartment. This permitted the use of an old style 1 quart filter. Total oil capacity with the engine filled to the full mark on the dipstick was 8 quarts. With the 1 quart over that GM recommended it had 9 quarts in it.

Stock Thermostat. I has this installed in both my 97 and 03Z. Before I installed it in the Z I ran an HPDE in the middle of August at the Glen. Temps were in the low to mid 90s and the sessions were 40 minutes long. Oil temp hit 319 degrees. Changing over to the DRM setup and coming back within a week the oil temp dropped to 230 degrees after a 25 minute session and coolant temp ran right at 200 degrees. This was with a stock thermostat.

The big problem with that setup occurred in the cool months. Since I drove the car on the street I couldn't get the oil warm enough when driving in 40 degree ambient temps. The Ron Davis Radiator puts the EOC in the passenger side tank and the radiator is a very efficient radiator. The passenger side tank is very cool.

I also ran a GMPP T1 transmission/diff cooler which helped keep the drive train reliable. It consisted of a pump, hoses and Fluidyne 13 Plate Stacked Plate cooler that was mounted in front of the AC Condensor.

Bill