blkbrd69

I play with a C6Z on road courses in Florida and am having oil temp problems with corresponding pressure drop caused by 290 degree 10w40 oil.

I am curious what other members that HPDE or race a C6 or even C5 have done for larger C6Z coolers. What temp. drops & oil pressure observations have you seen on track?

Daniel at Finspeed stopped production of his nicely designed C6Z cooler due to quality of core supply issues. Tried to find one and that started this spin-off topic.

When I installed a Setrab 625 oil cooler and Mocal thermostat with -10 lines on my old LS3 with no cooler I saw a 30 degree drop at Sebring in June.
Not going to be enough for this Z with 600HP, already have the Dewitt's radiator without oil cooler working on a vented hood.

I desire a 40 to 50 degree drop changing from the stock C6Z cooler on track, but also need warm oil street driving year round in Florida.

Looks like Anthony at LG Motorsports is designing his own, checking fitment & track testing now.

Breathless Performance has a monster double side mount cooler setup. I currently use air from fog light openings for brakes.

The Mocal thermostat, while it did do its job is kinda rough. It is wide, barely clearing an LS3's cats and really never trusted its flow potential -10 fittings but internal holes look small?

The Canton Racing remote thermostat is a monster that seems to be well proven, may be a bear to find a mounting spot for it. Threaded for -12 fittings.

Stopped by Improved Racing today on the way to work, met & talked with Michael the company president for the first time.

He great guy putting out a fantastic product for road course HPDE and racing applications.

His Low-Profile Oil Cooler Thermostat for LS Engines design and finish seems to top everything on the market I have seen yet.
http://www.improvedracing.com/cooler...80f-p-209.html

They also have a High-Flow Engine Oil Cooler Thermostat FSM (Flow Series Motor Sport) that looks like it would be at home with -12 lines hooked to it.
http://www.improvedracing.com/thermo...85f-p-212.html

I am curious if in our C6Z application with long lines and high flow ?? G.P.M.??, Should we use -12 lines instead of the forum normal -10. Or the tiny stock -8 lines with ^P bypass to promote flow with low ^P differential pressure? Seems Chevy went cheap with lines and fittings, then put a ^P bypass in to allow them to get away with it?

Reading and doing the math with the differential pressure ^P & flow charts from several hydraulic manuals and company charts they recommend at least a -12 line for our ??gpm oil flow capacity and line length.

Please post photos of cooler setups you have installed or built with corresponding track temperature drops.

Below are photos of the new LG prototype dual pass cooler and Improved Racings new thermostats, hope they dont mind me reposting pics.? Really want ^P numbers on these items.

blkbrd69

Here are photos of the Setrab 625 and Mocal where I dropped temps 30 degrees on my previous C6 coupe with no cooler. You can see how close the Mocal is to an LS3 cat.

blkbrd69

Finspeeds cooler now not made anymore. But we wouldn't be having this discussion if I found one to purchase.

Hope Daniel and Howie don't mind the photo theft?

parsonsj

Great start! I've just returned home from out of town, and I was wondering about this subject the whole time I was gone.

My oil temps on Florida tracks often approach 280*, and I've decided to upgrade my EOC.

I think a thermostat is vital, either directly (like the IR one above), or indirectly via a water to oil cooler (using the engine coolant as a thermostat). Running engine oil at 140* for 30 minutes on a daily-driver basis just can't be good either. Ideal oil temps are above 212* and below 250*.

I'm watching the LG Motorsports prototype with interest, but am thinking I'll end up designing my own with a thermostat and a Setrab core.

DeltaP and DeltaT data are vital though, so plumbing ID and restriction is what I'm mostly worried about.

Coach62

All I did was change my oil to 15w 50 and my temps never went above 248 degrees. Mobil 1 of course. Seriously, give it a try. Nothing to lose but a few qts of oil. Oh, and the m1 filter also.

wstaab

I have a Z06 with a modified LS7.
Finnspeed oil cooler, DeWitts radiator, Improved racing Low-Profile Oil Cooler Thermostat, -10 lines, Katech oil pump, 11 quart modified oil tank, and vented hood.
The thermostat works as advertised. I use a 212 in the winter and a 180 in the summer. You can swap the thermostats in the Improved racing adapter.
Oil pressure is not an issue with -10 lines and 5w40 synthetic.
On a 90 degree ambient day under track conditions water temp maxes out at 220 degrees, oil temp is 240 to 260 from the oil cooler to the engine. Oil temp in the bottom of the dry sump tank is 10 to 15 degrees less than oil going in to the engine.
This shows there is some oil cooling as it flows from the top to the bottom of the oil tank.
I just installed a SPAL dual fan from DeWitts. Helped the temps at low speed and in the pits, engine cools down faster, but high speed temps did not change.
The problem lies with the A/C condenser in front of the radiator. It blocks some airflow. Similar Z06 without the A/C condenser runs 10 to 15 degrees less water temp at track speeds.

Mark2009

How can that be? Offhand I can't think of any particular heat source in the oil flow from the bottom of the oil tank, thru the pump, thru one corner of the block, thru the oil filter, then thru the oil cooler.

Or am I missing/misunderstanding something?

parsonsj

The oil temp sensor is on the bottom of the tank, so that's the temp we're all familiar with.

Perhaps an aftermarket sensor upstream in the system?

wstaab

I was surprised too.
This is a 12 to 1 compression motor using 100 octane unleaded Sunoco 260 fuel.
I have a STACK high end oil temp guage with data logging capability plumbed into the oil cooler adapter at the return from the oil cooler.
I am assuming that the oil from the tank passing through the passages in the pan, being compressed by the pump to 80 to 90 psi, down the galley on the side of the block, and then out to the oil cooler is adding temp to the oil.
With the stock Z06 oil cooler I was seeing oil temps as high as 290 F and water temps of 240 F.
Also the current hood is a CF Haltech with the vent over the radiator.
Log from a 75 F day. Oil temp is bottom of oil tank. Oil temp from cooler is logged by HPTuners in a different file.

blkbrd69

What happens when you type out posts at 1AM? You post in wrong section, ramble, mis spell and forget things.

Should this post be moved to the Road racing HPDE section?

Does anyone have data logs or imperial data of differences between -10 and -12 plumbing?

Temp drops with just a vented hood?

Does anyone, or everyone and I am just dense, remove the side fender vent trims? Looks like a big air restriction!

How large a cooler can we cram in a C6 opening without killing flow to water cooler?

Pumba

Matt,

I am not a fan of #10 lines for an oiling system. So, I have changed all my lines to #12 lines.

Next, I use a SETRAB 272M221-D oil cooler - http://www.setrabusa.com/pdf/ProLine...ass_112610.pdf.

This is one of their new multi-pass coolers rated at 70,000+ BTUs of heat rejection.



I also use a MOCAL AOT2-12HT oil thermostat - http://97.74.32.155/files/thermos$.pdf. This MOCAL thermostat comes with #12 AN fittings and has large openings.

I also did three other things in my oiling system that most LS owners neglect:

1 - I don't trust the bypass system in the LS oil filter housing. So, I remove the bypass plate and spring. I then tap the hole and installed a 1/4 pipe plug.

2 - I purchase a Canton Racing remote oil filter adapter - https://www.cantonracingproducts.com...ILTER-ADAPTER/

3 - I use #12 lines to plumb from the Canton Racing oil filter adapter to a Trans-Dapt dual of oil filter mount that I mounted in my left front wheel well behind the splash panel. With this oil system I never bypass oil around the filter. All my oil MUST go through my two filters. Because the filters are mounted in parallel they have less than 1/2 the restriction of the standard GM single filter that is used on an LS engine.


I also have changed over to the new Royal Purple 30-8A filters with their synthetic filter media.



I hope this adds to your knowledge base.

JR

Mark2009

You mean all those things aren't normal at all times? Ruh roh....

Might get more input / practical observations there.

I asked a prominent road racing vendor and got the impression that it would be maybe 10-15 degrees.

I'm thinking those are intended to get air pressure out of the fenderwell. Tires make a lot of air pressure (tread).

Probably not much bigger than what is already there, unless you remove the AC condenser.

Mark2009

Yeah, that looks real toasty. I'd try to sandwich a sheet of thin metal in there as a radiant heat barrier.

Mark2009

I guess but that seems like a lot of added heat, assuming the oil cooler is taking out 30-40F. I wouldn't think calibration would be that much of an issue but to really pin that particular mystery down is to put an identical temp sensor in the oil tank.

I'm really curious where your AIM picks up the oil temp info. I'm assuming via the OBD II port, if so do you happen to know or can you find out which PID? I've tried 221154 but it's a little flakey.

Mark2009

Back to the oil cooler discussion... a couple of things that are needed to know before trying to improve the stock system:

1. What is the flow rate of the stock lines.

2. What is the flow rate of the stock cooler.

If 27GPM is the max rate for the oil system, then I'd think that is a lot. If the coolant system is around 50GPM (semi-educated guess), then look at the size of the radiator and the radiator hoses.... the stock oil cooling system is nowhere near close to half that.

Setrab's website shows a flow rate of 8GPM for their 'dry sump' coolers (20W50 oil), with a delta P of a few PSI (varies depending on model).

An alternative (I suppose) if the stock lines/cooler are woefully inadequate is to insert a cooler on the big lines to/from the oil tank. This would clearly take big lines and a big cooler. Somebody mentioned a dual cooler setup, I think I've seen something like this (maybe same thing) on DRM's website. Looks like the coolers mount behind the fog lights or thereabouts. Looks massive, dunno how it is plumbed.

3. If the stock cooler is a major restriction compared to the stock lines, then as I mentioned before another cooler in parallel should help or of course a stock cooler replacement with better flow capability (and of course better BTU performance).

Edit: Found some info. First, web calculators for flow also want velocity. Don't have that number. But I did find a garden hose calculator (link) that wasn't so picky... 1/2" hose, 60 PSI, 25' long flows 30 GPM of water. 5/8" hose flows 56 GPM. I assume it would flow less oil (viscosity) but offhand I'd say the -8 OEM oil lines, some 8' long total, probably aren't a flow restriction -- unless the viscosity and a few bends makes a major difference.

Edit II: Those water figures are surely discharging to atmosphere. I'm thinking that if the discharge is into a confined system (like an oil cooler or an engine oil galley) then flow rate will be less. The more I read the more complicated this gets. Perhaps should stop reading . . . .
.

parsonsj

I understand about undue restriction of oil lines, and I agree 12AN in and of itself is a good idea. The issue is the 1/2" NPT with its nominal ID of .500 to .550, especially for ordinary aluminum fittings (like I see in your photos). 1/2" pipe fitting IDs are usually between 8AN and 10AN IDs, and so 12AN hose and hose ends isn't going to flow any better than 10AN, and probably not much better than 8AN.

Now if your NPT fittings were 3/4" NPT, then 12AN would have a lot more utility.

blkbrd69

Sold the Mocal. It had a thermal heat shield made from titanium and Koolmat, just not pictured.

The mistake on my part is posting the wrong max oil flow for the LS7, seems the flow I posted is for pressure and scavenge combined?? Used data directly from Chevy in a PDF showing changes for LS7 and got it wrong. Thank you Michael for pointing out the error.

What is the true pressure side GPM flow rate at 7000 RPM in a 2008 LS7 ????

I dont think Chevy cared about the flow rate of the cooler or lines as there is a ^P bypass installed in the block fitting.

Pumba

That has not been my experience or observation. #12 lines and fittings have much lower pumping losses than #8 or even #10 lines and fittings. #12 lines also radiate away more BTUs of heat than the smaller #8 or #10 lines.

Take a look at any professional race car's oiling system lines. You won't find any #8 or #10 lines and fittings. They use either #12 or #16. The oiling system on a high performance or race vehicle is the LAST PLACE you want to rationalize away from the best system.

parsonsj

We're in complete agreement on that.

It's the 1/2 NPT ports in the Canton oil filter adapter and the Mocal thermostat that are the limiting factor. The 12 AN hose and hose ends are under-utilitzed as a result of those port sizes.

parsonsj

Here's what I'm talking about: the black adapter is 1/2" NPT to 12 AN. The silver is 12 AN ORB to 12 AN. The difference in diameter is easy to see. A quick measurement shows that the silver fitting has 21% more flow area than the black fitting.

As an aside, the black adapter is XRP's finest and has a very thin wall on the NPT side, resulting in an ID of .550. That is the best you'll ever get with a 1/2" NPT adapter. Ordinary 1/2 NPT adapters are usually closer to .500 ID.