2000BSME

I have typically had cooling problems on the track, engine temperature as well as power steering fluid, and transmission oil, engine oil, and so forth. I've added a larger radiator, which didn't really seem to buy my much lower engine coolant temperature (??), an engine oil cooler, which I haven't had the opportunity to evaluate, a power steering cooler that I've also not had the opportunity to evaluate, and now I've added a better cooling system for my transmission.

The stock lines run from the transmission in the back, to the radiator in the front, were simply unacceptable. The lines were too small for such a long run, and not only that, they run right beside the headers, which only serves to heat them up.

Having just put in my STage 4 RPM transmission this summer, I wanted to make sure it was properly cooled from the get go.

First off, the long run to the front of the car was junk. I removed the #6NPT to #6inverted flare fittings on the transmission and put #6 (3/8") NPT to #6JIC fittings in place. Next I ran two 5' hoses to the backside of the rear suspension crossmember to the new transmission cooler that I bought from Summit Racing. A Derale fan powered cooler, the atomic series, I hope would do the job.



I ran power to the fan from the power antenna. The antenna is fused for 20 amps, the fan requires 15, and I don't think I'll be using the radio anymore this year. I just cut the wires going to the antenna, and routed them to the fan, with a switch up front so I can manually turn the trans. fan on/off.

I made a special bracket to mount the fan right behind the suspension crossmember. Hopefully this single fan will have enough cooling capacity all by itself. If it doesn't, I bought another one, and I'm prepared to hook it up in series or parallel if necessary.


There's hardly any room to mount the fan/rad. combo in this location, but I wasn't about to rely on the stock routing and location, it just wasn't acceptable to me.

My previous cooling combination was the stock-in radiator cooler, plus an additional cooler in series in front of the radiator/condenser stack. It was stacked plate in design, but no forced ventilation, and I think the small lines running beside the headers negated any cooling effect that my prior set up may have had.

I'm hoping that this setup works, and works very well, because I'd hate to have to let off the gas again, or ruin my transmission, because of poor cooling.

CHJ In Virginia

That location is awfully close to the exhaust. You are going to pick up a lot of heat from those pipes negating much of the cooling. The T1 coolers for the trans and diff are located on the side of the car behind the side Z06 vents. You might want to investigate a set of the side ducts and locating your trans cooler there. A little longer run of tubing, but a MUCH cooler location with a direct supply of cold air from the outside. There were several threads about installing coolers in this location - do a search.

2000BSME

I may put some heat shields in place as well. I would also like to wrap that part of the exhaust with header wrap.

I don't have any z06 vents.

thanks

Nzzz

I heard exaust wrap can cause a fire if oil or something similar leaked on it and it got hot enough to ignite.

2000BSME

yes it can act as a wick, , but I will have to use in in certain spots, and keep oil off of it.

2000BSME

well I put cans around the pipes to insulate the cooler, and still, within 4 laps or so, I was overheated.

I added another identical cooler, and lines, in quick fashion (I had planned this step before I went to the track), and that bought me another lap or two, but still overheating.

I just ordered a 3 additional quart capacity deep pan, and a cooler that dwarfs the other two put together.

If this doesn't solve my problem, I will have to begin looking at circulating more oil than the stock pump can. I hope I don't have to go to that extreme.

Every time I go to the track, I get significantly faster, and yet another system needs cooling. I hope my current plans will work.

pan:
http://store.summitracing.com/partde...w=1&N=700+150+

cooler:
http://store.summitracing.com/partde...5&autoview=sku

These items will introduce an additional 5 quarts oil capacity, and more cooling ability. Like I said, the only other thing I can think to address right now is pump fluid flow.

Dirty Howie

I feel your pain ..... A4 means extra heat everywhere.

My tranny stays 180-220 even in 100 degree demps. I have a huge cooler in front of the rediator condensor that bypasses the internal radiator cooler. I also have a B&M tranny pan.

I am currently trying to keep my engine oil cool

Good luck



DH

2000BSME

wow. WHen I say overheating, I mean trans overtemp warning comes on (250+). In just a few laps I get to 225, another after that and I'm at 244, and I decide to go do a cool down lap.

If I could see 220* steady, I wouldn't have a worry at all.

Allthrottleandsomebottle

I see 274 at the end of a hard session in 90+ degree heat........I just put in new fluid after 2 days running
That was before I put on the heat wrap from the headers back....and cut a small slot in the DS front air dam to help air hit the cooler.
You can also put heat sleeving on the trans lines.........
Coolant never gets above 230.....must be the speed I carry

Aardwolf

I have a cooler on mine and one of these:



Maybe there is one for your year as well.

2000BSME

I saw 270+ on my old transmission. I am trying to prevent that occurrence with my newer one, as changing if out wasn't that fun.

I am using header wrap in places as well, but I don't have them completely wrapped.
Most of what I've seen say that those types of pans don't work with the deep sump of the c5. I have already ordered an alternative.

thanks

fatbillybob

I would think it way more beneficial to increase oil flow with an external pump and make sure you have clean airflow coming from the outside. At least I would put the radiator(s) behind the rear wheels so with fans you get cool ambient air. A larger capacity will just get you another lap before overheating if the real problem is no airlfow and no flow.

Dirty Howie

Well I don't know about not worrying at all........

But I do know that shortly after I saw trans temp warning light at the track my tranny died



DH

2000BSME

I have thought along these lines as well. Larger capacity may buy alot. It means the oil will have more dwell time, just sitting around dissipating heat. I'll just have to see.

As far as an external pump, the problem with that is you would have to tap into the pan for supply, and dump the oil back into the pan... not terribly productive if you ask me.

fatbillybob

I hear you! I have done my own development on a car nobody uses on the track either and it is difficult to invent the wheel. There is a scentific way to do this. We need to find out the flow rate of the OE pump, its volume flow, and how fast you heat that flow to get some feel for heat generation ability and have a smart guy do some math to figure out what is the thermal load generated then you can buy parts to decrease and handle that load. I'm afraid that with more oil yes you have more dwell but is that dwell 2 more laps or 20? I think you'll just have a bunch more hot oil because you still have done nothing to throw off the heat. Getting to the overheat point W/ OE system in 4 laps is just crazy. You got a serious issue. Baring the use of an engineer for a math answer...I say call one of the sponcers like Lou Gillotti a really nice guy and perhaps he can give you some ideas eventhough he is not racing slushboxes. Otherwise you are just guessing. When I guess it always ends in frustration and it cost me too much too.

Bill Dearborn

Maybe the solution is to use a cooler in front of the car and run your cooling lines through a different path to get there. The GMPP tranny cooler for the manual transmission routes the cooling lines from the rear wheel well through the passenger side rocker panel and you might be able to do the same. This would get you away from the exhaust heat and get your cooler into some cooler air. I have my doubts as to how effective any cooler mounted under the car can be unless cool air is routed to it.

Bill

2000BSME

thanks, but the under the car cooler is now obsolete. I now will have to try something else out. Maybe the lines to the front will have to be looked at again.

Room is the major problem here. I can't find much extra room.

2000BSME

Just made it back from a great track event with the SCCA at Barber this Saturday, and I had a lot of time to prove out my new cooling system for the A4.

Here are some pictures of the mammoth cooler, and not pictured is a Hayes finned aluminum pan. The cooler and the pan add an additional 4 quarts to the 12 quart system capacity, for a total of about 16 quarts.





This current set up worked very well, better than I had predicted, but it won't be sufficient with hot summer heat next season. It got me through all of the 15 minute sessions (8 total) without getting above 240*F. It was nice for sure, but with the small #6 lines from the trans, as I expected, it was just a constant march to the inevitable 'overtemp' alarm. Luckily, the 9-10 laps that I was getting per session was not enough to reach that limit.

I am in the process of fabricating an additional capacity resevoir, of about 4 quarts, to up the system capacity to about 16, or 20 with dual resevoirs. This would probably buy me an additional 10 laps without overheating.

Ultimately, I will probably have to add a kidney loop recirculating pump/cooler combo on the pan oil itself, to actually bring the car up to 'race' duty.

I am rounding the track at 1:44:9's at my fastest, and more commonly 1:45 and 1:46's are plentiful.

I could use a LOT of work on my smoothness though...

I'm probably approaching the limits of the car in some respects, as I have timed ex-pros doing the course in the low 1:40's in stock Z06's (c5's) with Hoosiers. I'm pushing very similar horsepower and 2004 z06shocks/sways/springs, my goal is ultimately to determine if and how much of a handicap the automatic transmission may be.

Right now, it's not the weakest link, that would be me, but I sure do find myself passing a lot of z06's!

Anyway, before I forget, yeah, there was not a whole lot of circulation in the trunk. -but their was a fair amount of turbulent convection cooling, due to the fact that I removed the tonneau cover. I have made an extension for the decklid latch, to raise it by 2", and allow hot air to exhaust better, but I forgot to pack it before I went to the track. I will probably add ductwork and venting to resolve this problem completely for next season.

Just and FYI for anyone considering being 'fast' or 'semifast' in an automatic equipped vehicle.

Dirty Howie

Nice write up and pics. Never saw any coolers back there before!!!

Wonder what would happen if you fabricated a wing and the cooler was part of the wing?????


DH

yakisoba

Now that is a fine idea. Perfect for HPDE, where there just is no contact. Not so good for a race, where there can be contact and you want to drive after. I think a wing cooler would be very neat.

I've seen coolers in the trunk like that before, but never one that size.