Panoz Heating Issues

[aromocki]

Just wanted to share my finding with you in the hopes of lowering cockpit temperatures. I have a high horsepower unit with 480 at the wheels and also have a 4 speed dog box transmission. After about ten minutes of hard driving two things happen:

1) the transmission is so hot that I am sweltering inside my car even with a cool suit
2) the transmission becomes harder to shift as I cant find the gates due to the thermal expansion of the internals. It literally wont complete a shift.

I resolved both problems by adding a transmission cooler.

I ecently ran a 3 hour enduro and won overall. Throughout the first 1.5 hours I ran with no cooler on. I had a cool suit and a blower fan hooked up to bring cold air in. The cool suit worked until all the ice melted which was about 45 minutes and its the big cooler. The blower fan didnt work as the cold outside air was simply heated by the tubing of the blower inside the car and I just ended up blowing hot air on myself. I didnt start the race with the transmission cooler on as it was a wet track and I didnt think I needed it. When I flipped the switch on after 1.5 hours the cockpit temperature dropped by about 40 deg F. I also didnt miss a single shift once the cooler was activated.

Just thought this might help anyone running the same setup.

Another setup tip is springs.

I upped my springs 200 lbs over the winter (lowered it as well) and have to say that the car is slower as a result. I dont have enough mechanical grip coming out of the corners and the back end wants to snap when you engage all 480 hp. I am going to drop my springs 100 lbs and raise the car a bit and see what happens. The rear sway bar is on full soft as well.

You can see how low the car was based on the picture I attached.

[panozracing]

What is low? What are the height measurements form the frame to the ground at the axles?

[aromocki]

I will see if I can get that for you.

[Werling]

I have added "cool lovers" to my hood which has helped to lower temp. pictures on the post - Wing Spliter & Meats. I have had to add tape to the grill to get the temp up each morning I ran the car.

[Cobra4B]

Love the "Toyo Tires" sticker on the door with the massive fat "HOOSIER" on each tire

[aromocki]

Yes its silly, but they are a sponsor of the series I run so I have to have the sticker on there. Havent run on Toyos for 4 years now.

[aromocki]

I also have no louveres and my car runs so cold that we have to tape the front grill to get any engine temps.

[NZGTRA17]

Originally Posted by aromocki

Another setup tip is springs.

I upped my springs 200 lbs over the winter (lowered it as well) and have to say that the car is slower as a result. I dont have enough mechanical grip coming out of the corners and the back end wants to snap when you engage all 480 hp. I am going to drop my springs 100 lbs and raise the car a bit and see what happens. The rear sway bar is on full soft as well.

You can see how low the car was based on the picture I attached.

What were the front and rear spring rates of the +200lb springs?


Not surprised to hear of the heat related shifting issues with the Jerico box. Jerico recommend a cooler for road race applications and I understand they will not warranty a box used in road race if a cooler was not fitted.

Kel.

[aromocki]

The current springs are 850/500.

Thanks fore the tip on the cooler, looks like that was a problem!

[NZGTRA17]

Originally Posted by aromocki

The current springs are 850/500.

Thanks fore the tip on the cooler, looks like that was a problem!

No worries, reason I know is I used to run a Jerico 4 speed in my last car but only used it for sprint races of up to 10'ish laps. Didnt fit a cooler due to this and our ambient temps are a lot lower over here anyway (15 - 25 degs Celcius). Loved that Jerico though, they pull themselves into gear!!

Interesting feedback on the springs. Yes 850/500 is quite a lot higher than a lot of us run. I run on DOT's due our endurance class rules and have found that 550/350 works well for me on my local track. Car feels compliant but gets great traction coming off corners. I do not run a rear bar either. May need to fit one as we venture to other tracks though.

I have generally found that live rear axle setups like the lightest spring in the back of the car you can get away with. In my last car we used 175lb and 200lb rear springs. Any higher and like your car it would start to wheelspin/step out big time due to roll enduced loss of traction on the inside rear. With its low CofG the Panoz is a fair bit more forgiving in this respect thankfully.

Kel.

[aromocki]

I am going to drop the springs to 700/375 on a test day in June and see how that plays out. I had 550/300 on it originally and it was fast but it was wallowing in the corners. I felt like I was driving sideways all the time. We lowered the car as well when we went to the stiffer springs and I dont think the suspension geometry liked it either. That coupled with the Detroit Locker made a whole lont of things worse.

When I say I am not happy with it I am only 1 second off my best time last year but the car is not forgiving at all and I have to fight it the entire time. I think the softer springs are the ticket.

One other intersting note is that the Hoosiers have a far softer sidewall than the Goodyears so with the current setup they are a much faster tire for the car. Good for one second a lap. They also lasted the three hour race perfectly so I have to say that I will stick with the Hoosiers.

[NZGTRA17]

Originally Posted by aromocki

I am going to drop the springs to 700/375 on a test day in June and see how that plays out. I had 550/300 on it originally and it was fast but it was wallowing in the corners. I felt like I was driving sideways all the time. We lowered the car as well when we went to the stiffer springs and I dont think the suspension geometry liked it either. That coupled with the Detroit Locker made a whole lont of things worse.

When I say I am not happy with it I am only 1 second off my best time last year but the car is not forgiving at all and I have to fight it the entire time. I think the softer springs are the ticket.

One other intersting note is that the Hoosiers have a far softer sidewall than the Goodyears so with the current setup they are a much faster tire for the car. Good for one second a lap. They also lasted the three hour race perfectly so I have to say that I will stick with the Hoosiers.

Let us know how the spring change goes.

Did you do any bump steer checks when you lowered the car? Somethin I always do now as this is a real killer regards ease of driving the car if the bump curves are out. This often is the case if you lower the car significantly. Easy to make up a couple of bump steer boeards with some plywood or customwood and some hinges. I use a $20 homemade set and they work fine.

Kel.

[boothkc]

One other intersting note is that the Hoosiers have a far softer sidewall than the Goodyears so with the current setup they are a much faster tire for the car. Good for one second a lap. They also lasted the three hour race perfectly so I have to say that I will stick with the Hoosiers.

We run the Hoosiers too on 18x10F & 11"R (SCCA GT2) and have found that they are great for about 5 heat cycles and then they really start to get hard and drop off in grip. This is well before we come close to getting down to the wear limits. I now run a new set each race weekend. Practice on last race set, qual and race on news etc. They do well for endurance races, however, and have run 2 4h races (won both) on a single new set w/o any real loss at the end. If I run them up to 10 heat cycles (still not to the wear indicators) lap times are off 2-3 sec/lap. Not sure if this is typical of other slicks as I have only used the Hoosiers. Grip is good after one lap and degrades a bit pushing hard (rear gets a little loose) after 10 laps of a 20 lap race. As a comparison we run 1:55-56s at Thunderhill CA and the GT2 record (997 Cup car) is 1:54 so we are getting alot out of the GT2 spec Panoz.

Brian, I think they are about $425 each from Tire Rack.....I try not to look at the prices!!
Kevin

[panozracing]

I think those are radial slicks like Michelin, Pirelli, etc. Aromocki runs bias ply Hoosiers. All together diff. animal.

Tire rack sells A6/R6 which are DOT legal tires and are not even considered slicks. Is that what you are running?

[aromocki]

Just letting everyone know that I completed the test day and dropped teh springs to 700/375 and that completely fixed the stepping out problem that I had with the Detroit Locker. We also raised the car to be 1/2" less than factory recommended height. Not sure if this did anything but the car was flying at the end of the test session with more speed to be found in every corner. I literally couldnt beleive how well teh car was hooking up.

I broke the input shaft of the transmission on the last session and will likely toss my TEX 101 transmission. I beleive its over ten years old and doesnt owe me anything. I am now going to a new NASCAR Road course 4 speed dog box. My friend has one in his Transam car and it shifts like butter. I will let you know how well it works and I am paying about $7.5k for it and I beleive its rebuilt and likely costs double that new.