Springs/Brakes/Spin

Hey guys. I am experiencing a problem with my brake positioning. I have wide feet-haven't bought racing shoes yet. All too often, while braking hard I end up also depressing the edge of the throttle. I recognize this when the car isn't slowing properly and I subsequently push through harder causing the wheels to lock up. This result necessitates getting off the brakes to regain steering authority which has on rare occasion caused me to miss the turn in point. Hence check out the link to the world famous corkscrew at Laguna Seca. The damage was done (passing the turn in point) before the photo sequence starts but it does show the aftermath of being "significantly off line in the dirt". http://gotbluemilk.com/web081208/69/index.html

This car was once part of the women's racing series which may explain the narrow pedal positions. My first solution is to buy narrow shoes-any recommendations?-if that doesn't mitigate the problem I believe the solution would be to cut/reposition/re-weld the pedals. Any other suggestions?

If you take time to look at the photos you can see significant body roll. (non-spin shots) These are the stock springs. I have a set of 550# springs to put in the front and switch the existing fronts to the rear. From all the feedback I have heard this should be a good solution.

An easy alternative is to lower the throttle pedal buy adjusting the cable/linkage. You may also have to adjust the stop to ensure that you still get full throttle...wouldn't want to leave any of that 250 hp on the table. :lol2:

Craig

Get yourself a set of snug racing shoes and practice in the shop. You need to brake with your the most sensitive part of your foot so you can feel the limits of the brakes (I use my toes and the ball of my foot to make the tires squeak at me). You can't do that with a thick shoe.

If you do have racing shoes and wide feet like I do. Then you may need to move the pedals. But I just practice foot placement in the shop and then at the track when its time to brake I'm good.

But heres my trick... I KEEP THE BACK HALF OF MY FOOT AWAY FROM THE PEDALS.

Shape your foot like you have on high heels (during braking and acceleration) and feel through your shoe the pedal so you are aware of where you are on the pedal and you have the distance memorized and can compensate and tweak when you change fomr pedal to pedal.

You need to memorize this distance as in order to be fast you have to go from wide open throttle to absolutely slamming on the brakes. DO NOT TAKE that car settling breather in between wide open and braking, it will cost you a half a second every time you do it.

When I am doing an outbraking maneuver I almost overlap them and brake with my left foot and then switch back at the apex of the corner so I can downshift and come out in the correct gear. There is time..it just takes practice.

Also left foot trail braking to turn the car and then already have your right foot hovering or lightly resting on the accelerator to get away from the apex is awesome in the rain.

Patrick James
PRO SYSTEMS

Racing shoes will make a big difference in your pedal feel. I buy simple G-Force shoes and replace them every year. Adjusting the throttle may also help as suggested, but don't lower it too much or your toe/heel will suffer.

Thanks for the input-all very good information. My tennies have to go regardless.

Yes Tennies have to go, I have a size 12 and VERY wide feet as well, and racing shoes make all the difference in the world. This car has been pretty easy to heal/toe and modulate the brakes.

As for springs, panoz26 just upgraded to 950/800 and the car feels great. I will be changing over to 850-750

Bumping up a few hundred pounds on the springs will eliminate the body roll but will also change the speed at which the car transitions weight, so be aware the car will change.

panoz used such low spring rates to make the cars easy to drive...

Yes Tennies have to go, I have a size 12 and VERY wide feet as well, and racing shoes make all the difference in the world. This car has been pretty easy to heal/toe and modulate the brakes. As for springs, panoz26 just upgraded to 950/800 and the car feels great. I will be changing over to 850-750 Bumping up a few hundred pounds on the springs will eliminate the body roll but will also change the speed at which the car transitions weight, so be aware the car will change. panoz used such low spring rates to make the cars easy to drive...

Those are super high spring rates. Let me now how that works out. No rear stabilizer I assume.

Those are super high spring rates. Let me now how that works out. No rear stabilizer I assume.

The car was awesome with the new springs -- body roll is gone - especially in rollercoaster at VIR .... I'm planted now :naughty: :iceslolan

Those are super high spring rates. Let me now how that works out. No rear stabilizer I assume.

keeping it for now, although with the higher spring rates it won't be doing much!

The spring rates all but eliminated the body roll and devin feels the car is more stable.

I am reinforcing the shock mounts on the cars to make sure they can handle the higher spring rates without worrying about fatigue.

I just bought 550# springs for the front and am putting the 350's on the rear. I am hoping that will be a nice improvement. I was going to corner weight and align with those new springs. I'm still running the 5.0L Explorer motor. I'm guessing this setup will work for now until the day that I switch out engines and have to reset the suspension again. Would love to hear others weigh in on those high spring rates as well with the larger V8's.
Eric and Devin-what springs were you running before the change?

I just bought 550# springs for the front and am putting the 350's on the rear. I am hoping that will be a nice improvement. I was going to corner weight and align with those new springs. I'm still running the 5.0L Explorer motor. I'm guessing this setup will work for now until the day that I switch out engines and have to reset the suspension again. Would love to hear others weigh in on those high spring rates as well with the larger V8's.
Eric and Devin-what springs were you running before the change?

Mine had the 550/350 setup -- and, yes, I have the springs if anyone wants to purchase a good / used set.
Wess, I still need to send those damn windows......

Mine had the 550/350 setup -- and, yes, I have the springs if anyone wants to purchase a good / used set.

What data lead you to believe that those springs were incorrect? Too much spring can hurt the performance just as much as not enough. I ran mid ohio with 900 fronts and it was WAY too much (you could feel the tires skipping). Ended up at 500 fronts. We bring about 10 diff. sets with us and tune into the correct one. Its diff just like running diff tire compounds and shocks settings. I dont think there is 1 spring that is the best its setup dependent.

What data lead you to believe that those springs were incorrect? Too much spring can hurt the performance just as much as not enough. I ran mid ohio with 900 fronts and it was WAY too much (you could feel the tires skipping). Ended up at 500 fronts. We bring about 10 diff. sets with us and tune into the correct one. Its diff just like running diff tire compounds and shocks settings. I dont think there is 1 spring that is the best its setup dependent.

Didn't say they were incorrect at all. It was probably more of a personal decision..... I did not experience the skipping effect at VIR, but, I would tend to agree that there is not 1 spring that is the best......but, from what I felt with the car at VIR Full, it was a nice change. I felt tight where I needed and wanted, no bouncy, no body roll causing scraping down rollercoaster.... car just felt solid.

Wess,
we should look at your peddles as our 3 cars have pretty wide spacing. I can't heel/toe well when I wear racing "elf" shoes such as Pumas etc. I end up using my Piloti sneakers (with Nomex) to get a wide enough base. I wonder if yours have been narrowed....go by Tom's shop (Competition Autowerks in San Ramon) and look at the 3 cars (2 GTS and 1 GTRA) as they are all the same and pretty wide. I is possible to hit the break and gas at the same time, but practice should allow proper heal toe which is important in a V8.

The 800 or 900# springs seem pretty high as the GTS specs are 550/350 I think. GTRAs use the Koni shocks, not Penske but aren't that different. We put 500/350 in the GTRA to keep it fun/forgiving for friends and it is much better. Almost impossible to drive well with 350/200s that it came with.

Oh BTW the dirt line down the corkscrew has won many a race....nice to see you are practicing it.

Put the 550/350s in and run some Hoosier R6s (275x17 on all 4s) and you will jump up several levels of fun.

Kevin

Wess,
we should look at your peddles as our 3 cars have pretty wide spacing. I can't heel/toe well when I wear racing "elf" shoes such as Pumas etc. I end up using my Piloti sneakers (with Nomex) to get a wide enough base. I wonder if yours have been narrowed....go by Tom's shop (Competition Autowerks in San Ramon) and look at the 3 cars (2 GTS and 1 GTRA) as they are all the same and pretty wide. I is possible to hit the break and gas at the same time, but practice should allow proper heal toe which is important in a V8.

The 800 or 900# springs seem pretty high as the GTS specs are 550/350 I think. GTRAs use the Koni shocks, not Penske but aren't that different. We put 500/350 in the GTRA to keep it fun/forgiving for friends and it is much better. Almost impossible to drive well with 350/200s that it came with.

Oh BTW the dirt line down the corkscrew has won many a race....nice to see you are practicing it.

Put the 550/350s in and run some Hoosier R6s (275x17 on all 4s) and you will jump up several levels of fun.

Kevin

I agree anything is better than 350/200 your car came with. Try the 550/350 and show the "expensive" german cars who's boss!

Put the 550/350s in and run some Hoosier R6s (275x17 on all 4s) and you will jump up several levels of fun.

This is great advice. I have changed to the 550 / 350 set up and am running on 240/625/17 Dunlop D11 compound slicks. Track I run on is very fast with average lap speed of around 100mph. There are some very fast sweepers, around 125mph, and some nasty bumps. The 550 / 350 spring set up is sufficient for the car on this circuit with the slicks and the Koni's (rebuilt and running synthetic oil) seem to handle the spring level with no problem. I have not fitted a rear bar as yet and do not feel that this is required the way the car is handling, even with a full 32 gal fuel load.

I've put 550/350s in my car now w/ fresh konis and a GTS rear bar but haven't had it out tot he track and won't untill Feb or March.

Thanks everyone; for all the good feedback-Kevin let's definitely compare pedals. When I bought my car from David on the test drive I noticed (and commented) that they were closer than the other cars he had. I have now ordered the narrowest shoes I could find and still fit my paddles into. When they arrive I'll check it out. I still think I'll have to rearrange the pedals.

Re: My screw up on the corkscrew-if you are going to blow it; it may as well be somewhere world famous, eh!

I'll give the 550/350 set up a try-based on everyone's comments its a good place to start. I'm looking for a good all around compromise as I really don't want to be switching springs on a regular basis-doesn't make any sense at my speed level.

In the new year I am considering changing to Kumho Ecsta V710 tires. Lots of you guys have recommended them over Hoosers. Anyone try Toyo's? A friend of mine swears by them in terms of adhesion and wear on his NSX.

I was told I will need rear trailing link brackets for strength as well as a replacement set of the aluminum front steering arms. My steering arms have been machined with a sharp edge transition-thereby creating a potential stress riser. I was told that with slicks both those items could fail under the new side loads. Is this true, by anyone's experience?

Eric nice update to your photo.
Devin no sweat on the windows-anytime!

Eric nice update to your photo.
Devin no sweat on the windows-anytime!

Thanks!

Look at the post "chasis band aid for slicks" http://www.automotiveforums.com/vbulletin/showthread.php?t=880516&highlight=frame+brace

To see what you need. Not sure about the aluminum issue, but I can tell you that we have broken a Panhard bar (lacked shear box), broken spindle, various body mounts on the GTS cars. Not sure the GTRA cars are fast enough to break anything, but maybe with slicks. See if you can order a new pedal box from Panoz or find some elf shoes. Tom and/or Ricky can do all the welding and frame reinforcements as they are grafting a new rear half onto Joe's GTS after the Ilgen Enduro crash (Competition Autowerks 925 838-1911).

We have replaced the spindles on the GTS cars and will do every 2yrs from now on. Should be on the list. Available directly from Coleman.

The V710s and Hoosier R6s look about the same so would be good to get some data to compare. You could probably run a whole track day season on a single set of R6s. Next season I'll get a set for the GTS and we can see how the lap times compare....they are cheaper!

Kevin

Look at the post "chasis band aid for slicks" http://www.automotiveforums.com/vbulletin/showthread.php?t=880516&highlight=frame+brace

To see what you need. Not sure about the aluminum issue, but I can tell you that we have broken a Panhard bar (lacked shear box), broken spindle, various body mounts on the GTS cars. Not sure the GTRA cars are fast enough to break anything, but maybe with slicks. See if you can order a new pedal box from Panoz or find some elf shoes. Tom and/or Ricky can do all the welding and frame reinforcements as they are grafting a new rear half onto Joe's GTS after the Ilgen Enduro crash (Competition Autowerks 925 838-1911).

We have replaced the spindles on the GTS cars and will do every 2yrs from now on. Should be on the list. Available directly from Coleman.

The V710s and Hoosier R6s look about the same so would be good to get some data to compare. You could probably run a whole track day season on a single set of R6s. Next season I'll get a set for the GTS and we can see how the lap times compare....they are cheaper!

Kevin


Do you have the PN# for the spindles from Coleman?

The nice thing about the R6's, have them heat cycled and the first weekend they run about 2 seconds a lap faster (at Sebring for example).

But from then on they fall off that 2 seconds, BUT then don't go any slower.

So you can use them to develop your car. We put easily over 25 heat cycles on a set and were only half way through them.

Were even wearing them at about 15 heat cycles when we set the short course track record at Sebring.

A good tire.

Patrick James
PRO SYSTEMS

We put easily over 25 heat cycles on a set and were only half way through them. Were even wearing them at about 15 heat cycles when we set the short course track record at Sebring.

I have never run the short course but what times are you running with the long course? What car/engine are you running? I never ran DOT tires on the panoz except 1 try at Mid-Ohio and coming from slicks we felt out of control. It was really bad and I wont try them again. When we ran a 400hp 911 RS America (about 4 years ago) we got about 10 cycles and the tires were worn to the chord. I cant imagine running them 25 times. Are you going slower to get that life out of the tires?

Do you have the PN# for the spindles from Coleman?

Buy them from Panoz and you dont need the number. Anyone check PAnoz number against alternate sources?

They were about the same price from Coleman or Panoz and I prefer to support Panoz when able. Last set Pz was out so we got some from Coleman.

Kevin

LAP TIMES and Tire Longevity. There is a variable here. The last weekend we took it out, we were doing testing for Edelbrock as we already had the Championship sewn up. Their new cylinder heads took our standard 306 combo from a 6600 rpm shift to 7600 rpm, so we gained a lot of power at my last event and unfortunately didn't get the true potential out of it. The track was very wet in turn 17 and a few other spots around the track. But I ran a 2:28.3 and qualified number one. But just swapping out the back and front straight and Turn 17 and splicing in a normal day on my GPS data logger it was a 2:23. I think the car would easily go 2:21's if it was on January on a cool track. It was 90 and humid out. We alos had our Daytona 3.55 gear in the car and needed our 3.90 gear in it. But we thought the new heads (with smaller ports) would reduce our rpms not increase them so we left the Daytona gears in it. So teens is a possibility.

Our Sebring record on the shorttrack is 1:17 and it was a record hot day at Sebring (an unbelievably greasy track) I had to downshift big and use the clutch as an emergency brake to turn the car for that lap. Just no traction out there. SO hot.

I personally love the R6 in the rain, very controllable 275-16 with 22 lbs of tire pressure and shocks on full soft. Adjust your rear bias so it trailbrakes to make it turn and throttle steer it out. My last race with the car (car is now retired and shipped up to our shop in michigan) I won the whole run group, passing GT1 cars and others with ease. But I like racing in the rain anyway, even with my shifter kart. Its great fun. Good tire, just don't overslide or overwork them on a dry track.

Try and keep your drifting to a very low slip angle and they will last and the car will go faster. If you hang them out (big drift angles), you go slower and can wear them out in a weekend.


Heres a link to the Hoosiers in the rain: http://www.prosystemsracing.com/111008news.html

Look at the post "chasis band aid for slicks" http://www.automotiveforums.com/vbulletin/showthread.php?t=880516&highlight=frame+brace

To see what you need. Not sure about the aluminum issue, but I can tell you that we have broken a Panhard bar (lacked shear box), broken spindle, various body mounts on the GTS cars. Not sure the GTRA cars are fast enough to break anything, but maybe with slicks. See if you can order a new pedal box from Panoz or find some elf shoes. Tom and/or Ricky can do all the welding and frame reinforcements as they are grafting a new rear half onto Joe's GTS after the Ilgen Enduro crash (Competition Autowerks 925 838-1911).

We have replaced the spindles on the GTS cars and will do every 2yrs from now on. Should be on the list. Available directly from Coleman.

The V710s and Hoosier R6s look about the same so would be good to get some data to compare. You could probably run a whole track day season on a single set of R6s. Next season I'll get a set for the GTS and we can see how the lap times compare....they are cheaper!

Kevin

Kevin, Thanks for the link on the chassis upgrades. When I get back from vacation I'll check out my car. Hopefully I'll get as lucky as the others who commented they had the reinforcements welded in place. I know by memory that I have the vertical gussets in place.

I'll contact Tom regarding these issues. I want to get my car to him for corner weighting and alignment as soon as I get the tires.

Sorry to hear about the Ilgen Enduro crash. How bad was it?

Joe's GTS was hit in the back then spun into other cars in lap 1 turn 1 at Thunderhill. The rear tube frame crushed and the full fuel cell was crushed about 8" (no leaks). Every corner was then hit. We can save the roof! All other plastic is being replaced and Panoz is making a new rear frame to graft in. Nice thing about these cars is everything is "fixable".....guessing $15k to fix. Tube frame is still straight.

Kevin

Man, that blows!!!