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Northern Rider
07-02-2005, 08:44 PM
How To Drive an LX Hemi on a Competitive Circuit

(http://www.300cforums.com/forums/showthread.php?t=7184)


Ever since I posted my experience with my 300C at a road race circuit (http://www.300cforums.com/forums/showthread.php?t=7184), I have had requests to post some basic guidelines for novices wanting to take their LX car to a competitive driving event.


If you plan to take your car onto an Autocross course, a Solo I event, a driving school (highly recommended) or laps at a road circuit, then here are a few tips to make your experience more enjoyable.





Car Preparation



Remove all loose objects from the trunk and inside the car. Some venues will even insist you take up loose floor mats.



Ensure your windows are really clean, inside and out. You want to ensure that you have no glare during your event.



Check oil; radiator reservoir; brake fluid levels.



Make certain there is no brake material built up on your rotors. If you can feel ridges on the rotors, then be sure to Bed in the brakes. See BEDDING BRAKES (http://www.zeckhausen.com/bedding_in_brakes.htm).



Ensure your fuel is topped up to full. Competitive driving sucks up the gas quicker than you realize. Make sure you are running the recommended octane level.



Set your tire pressures at 40 to 45 psi., if you are running the OEM Continentals. If you have a different tire, go 10 lbs. above the recommended normal pressure. Ensure all 4 tires are set at the same amount. A digital gauge will give you the best read out.







Driver Preparation



Wear loose comfortable clothing. Footwear is very important. Wear a soft shoe with a flat sole – no heels. I prefer those inexpensive surf shoes. This will allow you to feel the pedals - especially the brake pedal. If your steering wheel is slippery, leather driving gloves are recommended. On my C, the top part is plastic, so I always wear driving gloves for events.



If the event requires a helmet and they do not provide them, don’t run out and buy a helmet – unless – you have checked out the specs to ensure it is SCCA or CASC approved.









Setting Up Your Driving Position



The driving position is critical to your performance and comfort. Most people sit back too far from the steering wheel. Set the seat and back the way you would for an office chair with the back quite upright. Place your left foot firmly on the Dead Pedal spot on the floor. Your foot should rest flat on this spot and there should be no pressure on your thigh. Move the seat forward and back, up and down until you feel comfortable with your left foot putting some pressure on the dead pedal spot.



Once this is done, adjust the steering wheel so that with your elbows at the side of your ribs, you can wrap your fingers around the wheel above the spoke, by bending your wrists.



You may find the wheel uncomfortably close at first. It is essential that your steering be done with your elbows and wrists bent. This is to ensure that you do not use your shoulders while turning the wheel. Here’s why: G-forces in the corners will attempt to shift your body to the left or right. Keeping your left foot firmly on the floor and your elbows and wrist bent will keep you from using the steering wheel for support. – a dangerous practice that will interfere with smooth, fast driving.





Set your 3 rear view mirrors carefully. As an oncoming car disappears from your centre mirror while passing you on the left, it should appear in your left mirror. Ditto for the right. You should not be able to see your own car in either side mirror.



Adjust the height of your seat belt so that it doesn’t dig into your shoulder or cheek. Drive with the windows open or closed; A/C on or off – whatever makes you feel most comfortable.









Getting Your LX around the Circuit Quickly



This is not going to be a driving school primer about braking zones, entry speed, finding the apex, exit acceleration, etc. You will get that at a driving school or you can read it on the net. Rather, I would like to discuss techniques that apply specifically to the LX Hemi cars.



Driving around a circuit quickly is all about limits and transitions. Every car has limits in terms of acceleration, top speed, braking, lateral G-force, tire adhesion, and the attitude (direction of the nose of the car). Being able to go out to the physical limits of the car and make the transition smoothly from one mode to the other is the mark of a fast car / driver combination.



Most LX Hemi owners are familiar with the superior acceleration of this 4 door family car. Some have taken it to the maximum speed (may be electronically limited to 126 mph). A few have tested the braking by deliberately approaching a corner and braking at the last second to reduce speed to a level that will go through the corner. And very few have pushed so hard in a corner as to discover the limits of lateral adhesion.



Ok, let’s roll your car onto the course. After starting the engine, punch the “ESP” button in the upper middle of the dash. This does not turn it off – it just sets wider limits before it intervenes with traction control, yaw control and anti-lock threshold. This is very important, as you will soon appreciate. Next, place the Autostick in 4th gear. This tells the computer to use crisper shifts and higher shift points.



Next you will learn the course by driving it slowly, preferably behind an instructor. Keep your eyes well into the distance, focusing on the second next task you have to perform. The immediate task will stay in your peripheral vision and you will have already done what you have to do to execute it correctly. Always try to stay focused one step ahead. Do not calculate speeds or RPM rates – you won’t have time to look at these when you get moving quickly.



Braking: Your Hemi has superior brakes. If it’s a C or R/T, you have 14” discs with ceramic pads. Despite its size and weight, your car is capable of stopping very quickly. The pedal feel is not as good as I like, but one gets used to it. Repeated hard braking will heat up the pads and rotors and cause some “fade” – softer pedal and less grab – longer distances. The fade is mild and the brakes recover quickly. You can get on the brakes hard and not worry about lock up as the anti-lock will kick in. Don’t bother shifting down for the purpose of braking. This is a waste of time because of the design of this modern system. Rely on the brakes to reduce speed.



Accelerating: As you go past the apex of a corner, you want to start to apply power smoothly as you continue the exit. Racing is very much about exit speed out of corners. You want to be in the right gear to get the most torque coming out. Here’s where the Autostick is neat! As you approach the apex (your slowest speed), slap the stick to your left, repeatedly. It will not go into a gear lower that is right for your speed. You don’t have to look at it or the dash to see what gear it’s in. Just slap to the left 3 times. That’s it! As you accelerate out, let the Autostick shift up on its own. Don’t worry about 5th gear. You won’t need it. Keep it in Autostick.





Transitions: Almost everyone has felt the smooth transition of this car as it changes from one force to another – accelerating; braking; turning. The smoothness of the LX is awesome. Guess what? It gets even better at speed as you push out to the limits. This is due to:

v the great unequal arms / IRS suspension design

v the very rigid unibody frame

v the amazing little computers from the E-Class Mercedes making constant adjustments out at the limits



The ability of this car to transition smoothly at great speeds is the best kept secret about this car. It makes good drivers into racetrack terrors. Not only can you drive quickly through the corners – you can – with practice, drift the tail out on sweeping bends, using a little left foot braking while keeping power on; trail brake up to the apex after your heavy threshold braking; hurl the beast sideways to get the 120” wheelbase around a tight hairpin; modulate superior acceleration out of a turn better than most everyone else on the track.



A Final Word



Your personal limits will most likely be below the car’s limits. Don’t be fearful of this car in corners. And, your Conti tires will scream in the corners. Don’t listen to them. Push yourself to make the next lap a bit faster than the last. It is very difficult to roll this car over, especially with the OEM tires. You would pretty much have to drive over a sharp elevation change such as a deep ditch to roll it. When you execute a corner properly, you will know it.



Trust your brakes – you can go from 60 mph to 0 in 122 ft.



When starting off as a novice, concentrate on racing against yourself.



Most importantly, have fun!

DAYTONA_R/T
07-02-2005, 09:01 PM
Make certain there is no brake material built up on your rotors. If you can feel ridges on the rotors, then be sure to Bed in the brakes. See BEDDING BRAKES.



please excuse my ignorance, but i thought you only bedded the brakes after installing new rotors or pads.... please elaborate for me as to why you would need to otherwise...

Northern Rider
07-02-2005, 09:04 PM
please excuse my ignorance, but i thought you only bedded the brakes after installing new rotors or pads.... please elaborate for me as to why you would need to otherwise...

I've posted this info here before under the Knowledge Base

Bedding Brakes (http://www.lxforums.com/board/showthread.php?t=13852)

Read the article by Dave. I run a fleet and have saved thousands of $$$, following these procedures.

DAYTONA_R/T
07-02-2005, 09:09 PM
I've posted this info here before under the Knowledge Base

Bedding Brakes (http://www.lxforums.com/board/showthread.php?t=13852)

Read the article by Dave. I run a fleet and have saved thousands of $$$, following these procedures.


ok... thank you, but you never answered my question at all... OUTSIDE of changing out the brakes or rotors... WHY would you need to bed in the brakes?

your post did not say to change out the brakes and then bed them in, just that if you feel ridges that you need to bed them in... my question is, why?

(i do not run a fleet but I do my own brake jobs, and am familiar with bedding in brakes when installing new pads and rotors...)

Northern Rider
07-02-2005, 09:17 PM
ok... thank you, but you never answered my question at all... OUTSIDE of changing out the brakes or rotors... WHY would you need to bed in the brakes?

your post did not say to change out the brakes and then bed them in, just that if you feel ridges that you need to bed them in... my question is, why?

(i do not run a fleet but I do my own brake jobs, and am familiar with bedding in brakes when installing new pads and rotors...)

Sorry, I'm so used to talking to guys like Dave Z and other racers. Rough rotors usually do not indicate grooves but rather ridges of brake material deposited on the rotors. This can cause pulsing and will diminish performance. Bedding will burn the material off and deposit a nice thin grey film on the rotor for optimum stopping power.

I bed in brakes routinely when they start pulsing or making noise, providing there is adequate pad thickness left.

Hope this clarifies.

LowGo
07-02-2005, 09:40 PM
Thanks NR. Very interesting post (as usual). The event I'm going to will be an "instructional" event, where an instructor will ride in the car during all track events. Since this is my first time, that should help keep me from making any major blunders (I'm sure the instructor doesn't want to roll).

Too bad you're so far way. I think it would be great fun (and educational) to be your "co-pilot" once! I'll let you know how my "diaper derby" turns out. :lol:

bigjim
07-02-2005, 09:48 PM
Fantastic write up. I have run two autocross events this year with my Magnum. The corner exits are fantastic if you modulate the throttle. If you simply paddle it you will evaporate the tires in one run!! as soon as I leave the event she "knows" it is quiet time again and won't spin the tires more than half a turn! Toooooo darn smart.

Jim

Northern Rider
07-02-2005, 10:56 PM
MyMaggieMae, it would be fun to lap together. I have a feeling you'll be just fine, with an instructor on board.

Let us know how it goes.

Bigjim, it is really amazing how you can get out of the corners fast with your car.

I bet you raised some eyebrows at the autocross with your big ole' wagon!

LowGo
07-03-2005, 02:17 AM
Hey NR, one thing I forgot to ask you. Would you do anything different in an AWD as opposed to the RWD?

Northern Rider
07-03-2005, 07:09 AM
Hey NR, one thing I forgot to ask you. Would you do anything different in an AWD as opposed to the RWD?

The AWD will actually grip better. No need to drift the back end out to overcome understeer. You can play with very low amounts of throttle through the corners.

The only thing I would do differently is to have the front tires 2 lbs less than the rears to help with understeer (the nose of the car wanting to move towards the outside of the turn).

bigjim
07-03-2005, 09:12 AM
MyMaggieMae, it would be fun to lap together. I have a feeling you'll be just fine, with an instructor on board.

Let us know how it goes.

Bigjim, it is really amazing how you can get out of the corners fast with your car.

I bet you raised some eyebrows at the autocross with your big ole' wagon!

Oh yeah, eyebrows, questions, comments from the announcer, even comments from a youngster about my corner exiting smoke show when I did a play lap. He seemed VERY nervous (his work station was directly in line with my exit) till one of the instructors set him straight, he seemed to think my 15 degree yaw leaving the corner with full throttle spin was an accident. The instructor pointed out that it takes skill and a great deal of experiance to do that. The way I figure it, if the car you drive is in the SCCA listing for classes (F Stock) the course should be able to be done with the car. Some of the corners are TIGHT as the primary cars on this type of set up are FWD four cylinders, Hondas, Subarus, and of course the Neon that takes first each race!! In autocross events in this group, half the classes drive while the other is at work stations on the course to reset cones and observe for off course mistakes. I got nervous at the last event when a mustang left a corner swapping ends with the driver in a total panic trying to catch it before he spun. He wisely did some slower laps to get the feel of it before trying to get close to the edge again. It is a bit unverving when the car is fishtailing back and forth and you can't figure out which way to run to get away!! We had a big maple tree to get behind at the last second if needed. This course used two parking lots on a hill side with a long island with trees in the middle. The transition between the two levels was where the trouble corner was. The corner was all loose patch material to add to the unpredicability of it. All in all it was a blast! I even got my 24 year old son Sam to bring my Intrepid (street prepared class), The depressing part was when I ran the intrepid for a lap I did better time with it, Of course it isn't stock so I guess when I get done with the mods I can do to my Magnum it will do ok. Sorry for the ramble folks.

Jim

Northern Rider
07-03-2005, 11:33 AM
Jim, those autocross courses are set up for short wheelbase cars such as Civics, Miatas, Hondas, WRXs, Evos, etc.

Our 120" wheelbases are a big disadvantage - but our handling makes it fair game to smoke the Stangs with their solid rear axles.

Solo I gives you a full road course to play on without rubbing wheels with other cars. Much more satisfying, imo.

bigjim
07-03-2005, 11:38 AM
I may have to look for some local solo 1 instead of the solo 2 I have been playing with. Limerock is 1 hour away and will be doing a BMW club run soon (no need to own a BMW to run with them). I just have a bit too much going on with Grandkids being born and two sons getting hitched this year! I have even given up on my motocross for the year, thats not normal.

DAYTONA_R/T
07-03-2005, 12:10 PM
Sorry, I'm so used to talking to guys like Dave Z and other racers.

sorry I didnt know that you started this thread for experience racers that would be well aware of this. I figured this thread was to aid others with less experience then you... not to tell other racers what they already know...

My experience is more with lifted trucks then with cars.... and I go off-road more then on the track with lifted trucks....

I was asking because I am selling my truck to get the Daytona Charger, and after driving an 87 suburban, a 99 dodge ram, and an 03 Avalanche... even though I watch alot of racing, I have not exactly owned vehicles I can race....

my truck is not this tall, but to give you an idea... I dont think I would be entering into an auto cross race with this....

http://www.clubavalanche.com/forums/thumbsx/post-108-1068930798.jpg

LowGo
07-03-2005, 02:40 PM
The AWD will actually grip better. No need to drift the back end out to overcome understeer. You can play with very low amounts of throttle through the corners.

The only thing I would do differently is to have the front tires 2 lbs less than the rears to help with understeer (the nose of the car wanting to move towards the outside of the turn).

Thanks NR. I'm really looking forward to this experience. I just hope I'm not the only newbee on the track. Maybe I should get one of those "Student Driver" signs to stick on my car! ;)