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-   -   ITS and Eprod Cooling and oiling questions (https://www.rx7club.com/race-car-tech-103/its-eprod-cooling-oiling-questions-1006529/)

Laxfreak3557 07-28-12 09:45 PM

ITS and Eprod Cooling and oiling questions
 
Today was the first time i tracked my car, a 1990 gxl, it's stock except for a catback exhaust. I live in southern california and temps today were in the upper 80's lower 90's. I was really only able to make 4 or 5 full effort laps before the temp gage in the car would start to increase. First off is this normal?

Secondly i was curious as to what the racers in scca classes use to keep there car's cool for extended lapping sessions?

I was also curious with what those cars do to keep the oil from sloshing around in the oil pan. Do they run pans similar to what pineapple racing sells? I'm not sold on the oil pan baffles that go inbetween your oil pan and engine block. It doesn't seem like it would do much to keep the oil from sloshing away from the pick up tube.

When i was running today my car would give the low oil buzzer everytime i took a right hand turn and my oil level was full...Thankfully there are only 2 turns on track that make the car do that so i'm not too worried. it's just very annoying.

Any help/info that can be given out to help with the cooling and oiling setups will be appreciated. I'm going out again tomorrow. I'm already hooked :)

Thanks everyone

jgrewe 07-28-12 10:56 PM

Easiest fix for oil temps is a second stock oil cooler. With stock porting you can run it in series with no problem(easy way) the ideal way is to run them parallel(hard way). That will take care of a lot of your problem. If it doesn't you'll need a better radiator. With a little thought you can save a ton of money by finding a stock car radiator from Griffin that fits in the hole and modifiy it to work with the in/out on the same side. You can find them used for about $75. I turned a cross flow unit into a dual pass just by moving the lower hose fitting to the right side, below the top one, and cut a slot in the end tank half way between them and inserted and welded a plate to block the fluid flow.

SCCAITS 07-29-12 08:34 AM

You'll want some real gauges to see water temp, oil temp and oil pressure. How high you rev the motor as well as ambient temps, AFR, etc. will play a role. It's not surprising you got the results you did.

I have managed to keep temps in range with a single cooler and Accusump for added capacity. I also run the car to 9k RPM in 100+ degree weather. This requires good ducting and a splitter though. Radiator is the AWR/Mazdaspeed unit that is around $600 but I have seen them on this site occasionally for $250 and would watch for a used unit. As for the pan, ISC used to sell a stock pan with a baffle plated welded in and it was pretty cheap from what I remember ($50?). 100% distilled water cools better than water with antifreeze, plus you shouldn't be on track with antifreeze anyways. Keeping these cars cool is a challenge and will require some money and work.

Laxfreak3557 07-29-12 09:12 PM

Thanks guys! I really appreciate it. I work as an intern at a porsche shop and it appears my boss has a spare 2nd gen oil cooler in the shop. Apparently our oil coolers are really good. The 914 and air cooled 911 guys love them. Anyway i'm going to put that on my car and run it in parallel. Any guidance or suggestions on that? I've heard it's better to stack the coolers core to core to keep airflow through them? We are planning on fabricating some sheet aluminum ducting to the oil coolers as well.

I still need to look into a bigger radiator but the stock car radiator is a great idea. Do either of you have experience with the water pump underdrive pulley's as well? Seems like a good idea but i do still drive this car on the street so i don't want to sacrifice daily driveability by underdriving the water pump

I appreciate your help

jgrewe 07-29-12 10:21 PM

I run both a smaller e shaft pulley and a larger waterpump pulley. I don't think it would be the hot set up on a street car though.

As for plumbing the cooler. I bring the oil out to a remote filter that has two in and two out holes. I use one in and two out, plugging the spare 'in' port. Oil goes through the coolers and can go back to the engine a few different ways. One way is to bring them together with a custom manifold and send it back to the stock location. Another way is to bring one back to the stock spot and another to a plate where the stock filter is.

The latest way I've done it is probably the easiest when you don't have the engine apart and can plan ahead. Take the stock banjo bolt that is used for the stock return line. Drill a hole in the head to open a passage to the hollow part of the bolt(straight down from the top) then go to a hydraulic shop and buy a -8 AN male fitting and weld it to the banjo bolt. You end up with a stock banjo fitting and an AN all in one piece and can return the oil in one spot.

Laxfreak3557 07-29-12 10:54 PM

Thank you i appreciate the input a ton. It's amazing how quickly you realize after tracking your car that power mods aren't important . . . it would be nice to lap full out for a whole session without taking a cool down lap. That's the goal of all of this. Do you have any recommendations on ducting? I'm not sure if it would be better to do individual ducts: one for the oil coolers and another for the radiator? or would it be ok to just duct them all together?

I was also curious if this is a decent way to mount the dual coolers?
Triple-R: FC3S Buildup - Chapter 3: Part 28

Since i work at a race shop we get dealer rates on ss line and an fittings so it wouldn't be very hard to source the parts . . . i would be mounting the two oil coolers stacked together though. I don't like have a large gap between them like that

Valkyrie 07-29-12 11:11 PM

It's totally normal for a stock car to need a cooldown after 4-5 full-throttle laps.

And it's not just your engine, it's your tires and you that need to cool down too.

There's a reason why endurance racing is called endurance racing...

At the very minimum you need a bigger radiator and a bigger oil cooler than stock (or you need to install one to begin with) for serious racing longer than a few laps. If you increase the amount of liquids you have with a bigger radiator, bigger oil pan, oil coolers, etc, you will increase the number of laps you can do before you need to cool off.

Wait, you work at a race shop and you don't know this?

FWIW I installed an oil pan baffle and my FC's oil buzzer stopped buzzing while autocrossing.

The primary purpose IIRC is to prevent oil foaming though...

Laxfreak3557 07-29-12 11:45 PM

Well i'm an intern at a porsche race shop . . . i'm still new to the racing game though. Porsches seem to do pretty well on temps stock for 20 minute sessions which is what we run.

I was just asking about what the general solution is on our cars . . . i know what to do on porsches just not our cars. They get a third radiator and a gearbox cooler. I just knew that its cars run extended sessions with a very similar motor to what is in my car so i thought i would ask the question here.

jgrewe 07-30-12 12:44 AM

Ducting is VERRRRY important. If you have two cores with air flowing through the you want them as close as you can get them or you better have a way to keep the air from leaking from between them. I try to give the oil coolers there own place to vent if I can. Enough air gets in through the stock grill opening if you use it wisely. I have one cooler hanging below the round frame tube right in the airflow and another near the top of the radiator, right against it. The lower one vents in front of the radiator with a curved duct that sends the air out the bottom.

All air that comes in the bumper/grill has to go out through a cooler/radiator core. The whole area is sealed up tight with box that fits the shape of the bumper and expands to the size of the radiator.

Valkyrie 07-30-12 05:38 AM


Originally Posted by Laxfreak3557 (Post 11173426)
Well i'm an intern at a porsche race shop . . . i'm still new to the racing game though. Porsches seem to do pretty well on temps stock for 20 minute sessions which is what we run.

I was just asking about what the general solution is on our cars . . . i know what to do on porsches just not our cars. They get a third radiator and a gearbox cooler. I just knew that its cars run extended sessions with a very similar motor to what is in my car so i thought i would ask the question here.

Race cars, right? Standard race prep includes putting enough cooling power in the car that 20 minute sessions are no sweat. I would bet you've got coolers in every part that gets hot... lol

Laxfreak3557 07-30-12 02:28 PM


Originally Posted by Valkyrie (Post 11173590)
Race cars, right? Standard race prep includes putting enough cooling power in the car that 20 minute sessions are no sweat. I would bet you've got coolers in every part that gets hot... lol

Actually over 50% of the cars that come out to our events are mostly stock 911's, Boxsters and Caymans. They do surprisingly well from the factory. There are a couple of stock time trial classes that these cars run in and they have no problem doing full effort laps for 20 minutes.

For our purpose built race cars we always add a third center radiator and since porsches have transaxles we add a gear box cooler as well. Since the diff shares the same oil as the gearbox that oil tends to get incredibly hot. Hence the needed extra cooling capacity.

I have decided to run dual oil coolers and i'm going to try and find a stock car style dual pass radiator. We can then fab up some ducting at the shop and hopefully that will keep everything cool. The next event i'll get to drive is in early October so i need to start getting parts together for that now.

Thanks for every ones input.

RockLobster 07-31-12 12:44 PM

1st priority = Ducting

2nd priority = Ducting

3rd priority = larger aluminum radiator, i have no issues with my basic koyo upgraded all aluminum. They make a dual pass that will bolt in but you will not be able to use a stock intake with it. The stock rad really is insufficient for track driving. This will take care of 90% of your issues.

4th priority = Oil pan baffle, or even better, a pineapple aluminum oil pan, which has built in baffles and windage, and since it is aluminum with fins and larger it increases capacity and cooling. Ive run one on an enduro car for a couple years now without any issues.

Now we are getting into the race arena...

5th priority = Upgraded or Dual Oil Cooler (run it in parallel) running two stockers in series is too high a cumulative pressure drop IMO. I would question whether this is needed for a car only used for 20min runs. I have never had a problem (on even my Turbo II with a stock single cooler) with oil temps, in a 20 min open lapping session. The only time we had issues with oil temps (with one stock cooler) are 45+ min races where we are up behind other cars for long periods of time.

6th Priority = Underdrive main pully, underdrive water pump pully. Constant redlining at 8k on the track cavitates the stock water pump too much...

After i did all this with my race car it can run full out for hours without issues.

Laxfreak3557 07-31-12 05:30 PM

Thanks Rocklobster! I already have the pineapple pan on order and i'm designing some duct work that will force all the air from the front opening into the radiator and the oil cooler. I think i'm going to flush the coolant system and refill it with distilled water and water wetter and then monitor it like before buying a new radiator and oil cooler. Aluminum is cheap and we have an abundance of it at the shop so that will keep me busy for awhile

Thanks again

j9fd3s 07-31-12 06:43 PM

another thing that seems to work, and is very easy to do, is buy/fab/find a lower radiator hose with a spring form, or put a piece of pipe or do something so the hose won't collapse.

it seems to actually help quite a bit. i'm running a totally stock cooling system, except the hose, and the radiator is new. in a 1st gen with a p port, and on a 90 degree day, the water temps are rock solid.

jgrewe 07-31-12 11:55 PM

^^^^excellent point! Your pump will suck that hose flat and cause all kinds of cooling issues that can't be figured out.

RockLobster 08-01-12 07:34 PM

Excellent point. I ran a silicone lower radiator hose and besides some weird cooling problems i could never get them not to leak when they cooled down to ambient. So, i ditched them and went back to the heavy stock rubber one that has the braided structure in it. Don't know if it is ideal with regards to preventing collapse but its WAY better than those stupid silicone hoses.

SCCAITS 08-03-12 08:32 AM


Originally Posted by jgrewe (Post 11173360)
I run both a smaller e shaft pulley and a larger waterpump pulley.


I have the dual sheave alt. and main pulleys but see they only make single sheave waterpump. I'm going to order the large waterpump pulley now to see if it reduces temps any more. Any idea why the S5 one is $79 and the S4 one $163? Can you not swap between the two?

Now is a good time to make some aluminum tubing radiator hoses as well. Currently just using silicone hoses with a spring inside but the spring always seems to get out of place.

jgrewe 08-04-12 01:09 AM

I have a couple of the big water pump pulleys and never knew there was a difference. I ended up turning one a little smaller on the OD on the lathe and had to open up the center hole that the pump shaft sticks through.

It fits now but it means I probably screwed up one of the expensive ones to fit whatever the combo I have on the front of my engine, lol.

SCCAITS 08-04-12 07:36 AM


Originally Posted by jgrewe (Post 11178707)
I have a couple of the big water pump pulleys

If you want to sell one I know a buyer :)


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