designfreak

So I could really use some help in brainstorming over my heating problems. My ITS spec engine was built just last year at ISC by Mike VanSteenberg, and I purchased all of his cooling goodies ( big aluminum radiator with heat exchanger, thermostat, high pressure cap, etc..). I'm running water with water wetter as coolant, and the radiator has no fans.

Running the car at Homestead (granted its a relatively small slow course), I get my temps up to 240 oil, and 230 water in about 3 laps. My eye is constantly on the guages and I know I shouldn't even be letting them get that high in the first place. Over half of my track time is spent on cool down laps.

I have the stock ECU tuned by a fuel pressure regulator on Mikes dyno. I cant run the revs up higher than 8000 so I wouldn't say that I'm pushing the engine to the limits.

I plan on installing some fans on the radiator before next event out, but I don't really think that this will resolve the problem 100%. Mike says that his cars all stay around 200, and no more than 210 in the water temps for long races with the same setup.

Am I missing something here? Mike says that he "would have to see the car" to tell me what is going on, although I've only ran it perhaps in 5-6 weekends since it left his shop, and I think the heating problems have always been as they are now right out of the box. I paid top dollar for all of his stuff, and I made sure we weren't scrimping on anything..wasn't expecting to have this happen with ISC's good reputation.

Any thoughts and help would be much appreciated!

SCCAITS

iTrader: (3)

Sounds like you have the right parts to make things work. I don't have Mike's radiator and heat exchanger, rather a Ron Davis radiator but have no doubt Mike's setup will also do the job. I'd definately recommend and e-fan, it's good for the grid on hot days. I also turn mine on when I need an extra little air flow during a race. You might also try 40 Below instead of Water Wetter, I switched and it seems to work better.

The biggest problem contributing to your temps is probably ducting. It took me several attempts to get enough air flow in there to keep temps in line. Just the smallest changes had a big impact on temps. If you don't have any duct work I don't know how you can make it work. It's a little difficult with IT rules, especially if you want to be 100% compliant (although you are not likely to get a protest). The splitter and radiator are free items, so as long as the aluminum ducting only attaches to the splitter and radiator it's 100% legal. The rules don't say it can't touch other parts, just can't be fastened to the body, etc.

Post up some pics of your ducting if you have any. If I'm not mistaken, the S5 bumper has a bigger opening than the S4 as well.

DriveFast7

iTrader: (1)

Let's see the ducting.

And, it could be the motor not the cooling systems. Iif the motor's spun a bearing or the plates were not level and lapped it'll run hot. Any number of other motor issues could be it.

Anything in the water and oil that doesn't belong?

designfreak

I will go ahead and post pics as soon as possible of the ducting as I have it run now. I do have the S5 bumper, and I even have all of the fog and FTP light openings unplugged as Ive set it up for track days, so theoretically it should be sucking up more air then normally allowed in its ITS legal setup. Instead of making the front splitter I was planning on I went the easy route and made an air dam, so admitedly with the splitter I should get a tad more air directed at the radiator, but Ive also seen plenty of people run with neither an air dam or splitter up front.

It would probably be a little strange with so little time on the engine after a full rebuild for it to have spun a bearing already I would think..but You never know. When it was at ISC I had him balance the full rotating assembly and polish everything before rebuilding.

Thanks guys for the oppinions!

Kentetsu

Shouldn't be getting that hot. How sure are you that the gauge is accurate? Is the timing correct? Belt on the water pump tight enough? As long as you are running at speed, the lack of fans should not be affecting the temps...

wrankin

Heat exchanger? I'm not sure I get this. How are you doing your oil cooling?

jgrewe

iTrader: (1)

You need to make sure any air that comes in the grill has to go through the rad to get out. Any little gaps can hurt your cooling. We run two stock coolers and a stock car rad and have no problems keeping things below 210F on both fluids.

SCCAITS

iTrader: (3)

The fog light openings should be ducting to your brakes. The FTP, might as well close them up as you need to for ITS. They are usually only used for air to the intake filter, I don't see how they are bringing more air to the radiator. Buy or make the splitter, Mike has an option, Flatout Motorsports has one and you've probably seen the DIY wood splitter which is probably the best way to go. Flip through this thread if you haven't already https://www.rx7club.com/2nd-generation-specific-1986-1992-17/my-%2430-splitter-solution-687730/ The splitter will add a good amount of increased air flow and also help to trap the air from escaping out the bottom.

designfreak

designfreak

Here are a few pics of my setup:



You can see that the bottom foglights are dedicated to brake ducts, while I actually (since I havent been running SCCA latelly) have ducted cool air up into the intake airbox from the turn signal lights and the FTP lights

designfreak

here you can see the heat exchanger and the ducting to the radiator. I am using the stock top ducts and then an aluminum plate afterwards to direct all the air there.

designfreak

designfreak

In the lower front of the radiator, angled downward I have the stock mazda oil cooler. Oil travels out of the engine into the oil cooler. afterwards it goes from the oil cooler into the heat exchanger behind the radiator. The heat exchanger takes water out of the radiator after it has been cooled and further cools the oil with it running it into a box side by side with the oil.

Under the car I have the stock plastic undertray, but it has been cutout to allow the oil cooler to breathe out. A little plastic flap tucks up behind the oil cooler to make a smooth opening for the hot air to escape under the car.

I know that this heat exchanger business seems a bit strange as Im sacrificing my water temps to bring down my oil...but I had numerous people vouching for ISC's system before I purchased It :/

designfreak

here is a pic of the splitter I was making out of fiberglass at home before I got lazy:

SCCAITS

iTrader: (3)

Not enough air can get through the front middle section where it needs to. Finish that splitter, you were off to a good start. Just keep the car on the track, with that splitter you were building 4.5" (?) below the front bumper any off is going to do damage. If you don't care about keeping the car ITS legal (which it's not now as you know), cut out the middle section like I did.

You can also take some aluminum sheet and block off the undersides and bottom so the air entering as no way out except through the oil cooler and radiator. Add to that some aluminum to duct the hot air that comes through the oil cooler to go somewhere other than the through the radiator.

designfreak

wow...beautiful car...lets see some more pics of it! Thanks for the advice guys.

Just to clarify ..If I were to cut out the little louvers in the stock bumper as you did it would no longer be ITS legal right? You really do have quite alot more air going through that radiator than I am.

wrankin

The GCR specifies that you cannot make new holes in the front of the car, so trimming out the grill like ITSSCCA does is verboten.

However, if you have a splitter with a hole in the middle (like your fiberglass mock up) you can and should duct it to the radiator.

I can't tell from the pics, but you should make sure that all air that comes in the main front opening must go through the radiator and cannot spill off the sides.

Did you remove the thermostat and plug the bypass hole in the oil cooler?

Are you running a stock thermostat in the coolant system? have you thought about drilling it to allow a little more flow?

Good luck,

-bill

jgrewe

iTrader: (1)

Show a pic of the underside of the area in front of the rad. That will show us more to maybe help you solve this with the parts you have.

Nice looking car by the way.

Another thing to remember, coolers work better when there is a higher temperature difference between the fluids(oil, air, water) You may get better results splitting the oil between the stock cooler and the exchanger so they both see hot oil from the engine.

designfreak

Thanks Jgrewe... you mean putting a T on the oil line coming out of the engine and feeding both the stock oil cooler and the heat exchanger with oil directly out? I was also thinking of perhaps trying the same setup a friend of mine has where he runs 2 stock oil coolers in series facing downwards in the space in front of the radiator with 2 fans pushing air out the bottom. If possible though as you mentioned I would ideally like to make it work with the parts I already have. I will try to find some pics of the underside to show...If not I will need to pull it out of the trailer and get some new pics of it ASAP.

jgrewe

iTrader: (1)

Running them in series is easier for sure but remember the temp difference issue. By the time the oil comes out of the first cooler it is much closer to ambient air temps. As it goes through the second cooler there isn't as much cooling effect.

If you are boarder line on having enough cooling with one cooler(which it doesn't sound like you are) series is fine. Run the "T" out of the engine, coolers in parallel, and bring them back together. I bring my oil back into the engine through a plate that bolts where the oil filter used to be. The lines come back from the coolers and go into each side of it. The oil is running the wrong way back towards the pressure regulator in the vertical galley but it does know any better. I used a remote oil filter mount with two in/two out to split the line to the coolers. I just ran one in and two out and blocked the fourth hole.

SCCAITS

iTrader: (3)

Thanks, yours as well! I don't want to hijack your thread though. PM me and we can trade, might give some new ideas.

Correct. Same with the missing FTP and turn signal which are used for flow to an air box where the headlight should be. I have a thread with more pictures on the setup from a few months back. I don't run ITS anymore, so I'm legal