Zak77

I currently have a good chunk of my engine bay apart as I'm putting in a cam/header package. I figure while I have it all apart now would be the best time to install an external oil cooler as the exhaust manifolds are off. My question is should I install a seperate oil cooler or a new radiator that has an oil cooler built in? its for my C5 coupe.

Wish I could figure out a way to install a C6Z06 rad as I have one sitting at home that I bought in a bundle with my coil overs.

At the HPDE events i've attended I've hit oil temps over 300 degrees in August. The most recent one, at Pocono, it was a bit colder and my oil "only" got to 275-280. Figure it's time to help the engine out and let it get better cooling.

This car will be used for HPDE, eventually time trials and hill climbs. No wheel to wheel racing though.

joenationwide

If you are fast, and you want your motor to survive multiple trackdays, you will want the standalone.

I just went through this decision last month. The combo rad/EOC is just too much of a compromise IMHO. I bought the DRM standalone EOC and the Dewitts radiator, and 2 weeks ago at Summit Main my max coolant temp was 217F and max oil temp was 237F, just like if I was cruising down the highway with stock cooling. Spend some money now, or spend more money and time later.

Zak77

Those are impressive numbers. My coolant is usually in the 250-260 range at Summit and oil is 300ish. Just driving my C5 on the street my coolant is in the 220-235 range as it always seems to run a little hot.

RedLS1GTO

I agree completely with the standalone. There is really no advantage that I could find for going to the radiator/EOC combo other than perhaps ease of install.


PM sent.

0Randy@DRM

There is really two ways of skinning a cat when it comes to cooling. The radiator with EOC does very well for dual propose cars. The stand alone does a bit better when it come to track only, high rpm, or high horsepower.

The stand alone coolers have been flying off the shelf over the past couple of years
http://dougrippie.com/products/stand...il-cooler-kit/

Here is the radiator link
http://dougrippie.com/products/ron-d...ers-t-1-legal/

Here is the comb unit with line kit
http://dougrippie.com/products/ron-d...-and-line-kit/

Thanks
Randy

Zak77

From a cooling standpoint I like the stand alone EOC, but with the funds I've alreddy spent the all in one is looking attractive. I thought about just adding the EOC but my coolant always seems to be on the high side. might just be my radiator is a bit clogged. Anyone know if a C6Z06 rad will fit in the C5? THis way I could do the EOC and use the C6Z06 rad that has been taking up space in my garage.

argonaut

I have the DeWitts with built in EOC. I've been doing this sport for years and run pretty damn hard. Typically I see oil temps around 230-240. In mid summer when its about 105 on track it will get up to 250. I don't however hit max revs on every shift, usually shift around 5500. For a dual purpose car where you are not trying set new track records it works just fine.

0JDP Motorsports

I would suggest going with a stand alone oil cooler set up like the DRM unit and an aluminum radiator. We use the DeWitts here primarily. These items are cheap insurance when compared to the cost of an engine and track use is engine abuse.

Kind regards,

Jordan Priestley
888.308.6007

bosco 08

Are these coolers thermostatically controlled?

froggy47

The built in warms the oil as well as cools, a consideration if the car sees any street driving (especially in colder parts of the country). Adding a thermostat to an external is a restriction to flow that some think is not really a good idea.

Zak77

Also, what are everyones feeling about thermostats? 160 vs 190? I'm going to put a new one in since I have everythign apart just not sure what temp to get. I don't tend to drive it when temps get below 40 as the tires are dangerous.

I have a great offer from a member for an external oil cooler which is very tempting. I'm just worried about not having the oil at a good temp for street driving as I tend to put 7-10K per year on my vette as I like driving it so much.

RedLS1GTO

There is a very easy way to get the best of both worlds, without comprimising...









Once you do it a few times, without even jacking the car up you can reach under and pull it off/put it on in about 5 seconds. Better cooling on the track, perfect temps on the street. If you wanted, you could even open up a partial hole in the cover to adjust to your specific street needs.

RedLS1GTO

Are you talking about water or oil t-stats?

By your wording I am guessing water. As far as the track is concerned it really doesn't matter. Once the temps are above the open point, which on a track is going to happen no matter what, it is all the same. Only difference it makes on the street is how quick you get from 160 to 190. Below 160 they are both closed and doing the same thing and above 190 they are both open and doing the same thing.

Zak77

Correct, water thermostat. Seems as though there are major battles over which temp to go with, and even what brand at that.

RedLS1GTO

I've seen that discussion for years and have never been able to figure it out. I'm firmly in the camp of that entire argument being a complete load of crap.

Like I said above, if comparing a 160 to a 190 for example, below 160 they are doing the exact same thing and above 190 they are doing the exact same thing. On a track you are pretty obviously going to be above 190, so it makes absolutely no difference which is in there.

trackboss

There is no reason to go to a lower temp water thermostat. The above explanation is good and water under 190 or so doesn't have advantage anyway. Cup cars run high pressure cooling systems and their water temp is often times well over what most would consider the red zone. Yet they make nearly 900hp.

SunnydayDILYSI

I run in red run group at HPDEs in Texas. Highest oil temps that I see are in the 250s with a Ron Davis combo during a 30 min session. I was hitting 290+ with stock radiator within 15 minutes and then backing off. If you want to be below 250, go with separate coolers. However, the combo takes a long time to get up to temp (160) at low speed. I expect the separate coolers will take even longer.

Bill Dearborn

I had DRM's Ron Davis Radiator with built in engine oil cooler on my 97 and switched it to my 03Z. Very efficient radiator and with the EOC in the passenger side tank I had problems getting the oil temp high enough when driving on the street. In cool weather the passenger side of the radiator felt just as cool as the ambient air so the oil was getting quite chilled. When I put it in my Z the on track oil temps dropped from over 300 to the 230 range and the coolant temp held at 200. I eventually installed a thermostat in the oil line so I could get the oil temp above 150 on the street. Of course with the external mount oil filter that held a quart of oil and with the extra quart GM said to run in the engine I had 9 quarts of oil which probably helped cool things down a little as well.

Bill