Switching from Asphalt to Dirt - Help Wanted

[T48]

First of all, if I'm posting to the wrong thread, feel free to move me. 

We're CONSIDERING running on dirt this season, as our asphalt track is history and a new dirt track is being built 8 miles from our front door.  As ya'll know, we were newbies on asphalt, we're even more lost on dirt.

 Here's my question(s) for anyone with the know how to change over from asphalt to dirt. 

1) What's different on the setup?  Anything?  Not asking for set up particulars here, more of a general question.  Like will our cut tires hurt us on dirt, etc.  Also, the track we're considering is high banked vs. the medium banked we ran last year on asphalt.

2) Engine cleanliness - I know how important is was to keep the air filters and everything else clean, tight, and lubed, will this be an even bigger adventure on dirt??  And what do you do about this in addition to your regular routine?

3)  Anything else I should be asking but don't have sense enough to know what it is. 

Thanks, guys, so much!!
Captainette

[justfreaky]

Hi Barb,
 Hope all is going well with you and the Captain.
Good to hear that they are building a track a bit closer to home. I'm guessing that you have already charmed them into running Legends Cars.
 Your going to need to change spring rates and camber. I think I posted a starting point for a dirt set up. I will look it up for you on my days off and send it to you. I'm not sure on the cut tires. The question to ask, is are tires cut differently for asphalt and dirt??? I'm not up on the tire cutting thing; but I would think the answer to be Yes.
 Get the local car wash to sponsor you! Your going to be doing a lot of cleaning after the races. Keep some extra outter wear on hand for your air filter. You may also want to shield the air filter from the flying dirt.
 Give me a couple of days, and I'll get you what info I can. Will this mean that we will finally get to see you in that sexy pink driving suit? 

My Best to the both of you,

Steve

[justfreaky]

This may give you some reference:
http://www.legendsracer.com/index.php?topic=289.0


Steve

[Tom Cole]

Barbara, your tires are cut fine for dirt.

[MegaMang]

I'm glad to hear you're going to give dirt a shot.  Everyone I talk to that races dirt thinks it's more fun that pavement.  I'm not convinced, but I've never driven dirt.  The point is, you'll still be racing.  Good on you.

Mike

[IraceLegends77]

One thing about dirt is that everyone has there own idea about what springs to use. I think that the springs that where posted will work but I like a little softer up front but that is just me. You will need your cross weight a little lower on dirt but this is all about track configuration like how much banking they have and such. Have fun and keep your sheld down and plenty of tear-offs handy.

Scott

[JGRacing]

As far as cleaning, get some Mud Off (or something similar).  You can get it from Speedway Motors or anywere that caters to dirt track racing.  Mix it with water and spray it on every place that will build up mud (inside of fenders, grill, underside of trunk, etc.)  It smells like something similar to WD40 and will keep mud from sticking as well.  This stuff is pretty cheap and a bottle will last a while. 

On the tire question, use whatever the softest tires are you have whether they are newer cut tires or uncut tires.  The heavier the track the more tread you will want, especially on the rear.   

I am going to put some sort of screen in front of the oil coolers to protect them from rocks and keep them from getting caked with mud.  If you can mount a screen loosly so that it can shake, it will held it rattle loose some of the dirt on its own during a race.  I'm assuming that screens are legal, since I have not raced one of these cars yet.    I think they sell pre-filters for the legends air filters, which will keep your filter from getting clogged. 

I would think that you will want your one available brake valve on the right front (that's what I am planning on doing).  It will let you use the brakes to get the car turning on corner entry.

Have not raced a legends car yet, but I would expect that most of this is pretty universal for any type of car on dirt.   

John

[T48]

Thanks to all of you, and keep the advice coming!  We've ordered the dust covers for the air filter, and I'm definitely changing the screen back out to the windshield!!  Hadn't even thought of that one!  Thanks JG for the the Mud Off tip, I was concerned about what to clean it with, although we were pretty sure the pressure washer and some WD40 were going to come into play here.

The set up - well, the track we'll practice on - weather permitting - saturday, and the track we'd like to run on are not the same track, so I'm sure that will be trial and error.  The smaller practice track is medium banked, the new track being built is definitely high banked and 3/8 mile.

So far it looks like the more work will fall to the pit crew! *shine a light over MY head* 

Uh, Steve, the driving suit is black, the helmet is pink, but Hon....................I'm way too old to look sexy in it if you sewed pink lace all over it!! *ROFL*

John, can you say the brake valve part a little slower for me again?   

[JGRacing]

The shorter track should give you a chance to pick up on the driving style with dirt and should help you get in the ballpark with setup. 

The brake valve mounted in the cockpit will let you take away some braking from the right front tire.  When you go into the turn and get on the brake, it will get the car turning.  Without reducing the right front brake, the car will want to just push straight under braking.  Shutting the RF off completely works great, but it looks like we cannot do that with a legends car.  My street stock didn't even have a caliper or rotor on the RF.  Linked below is an example of the valve. 

http://www.speedwaymotors.com/p/1977,8_Brake-Adjustable-Proportioning-Valve.html

Also, the Mud Off goes on the car before it goes onto the track and keeps the mud from sticking.  Sorry if I  made it sound like it was a cleaner.  Make sure that you do not spray it on your harness inside the trunk area (if it has petroleum in it, it could hurt the nylon webbing).  Below is a link for it.

http://www.speedwaymotors.com/p/2590,185_Mudd-Off-Keep-That-Mud-Off-Your-Car.html?itemNo=mud%20off
   

John     

[VMS Motorsports]

Maybe I misunderstood, did you say you were taking out a screen and putting in a windshield? Dont do it. Also, put a screen over the top of the carbs, if you've ever get a rock stuck in there wide open you'll know what I mean. Keep the tire pressures about half of what you ran on asphalt, and I don think anyone I run with runs cut tires.

my 2 cents

[Tom Cole]

Clarification...Clarences tires are cut, but not really camber cut like some of us use on asphalt.  They are  just cut to give better overall tire patch contact for better stability rather than top end speed.  I have worked on his car so I have seen them up close.

I love the shaker screen idea in front of the oil coolers.  Barbara, I'd say that keeping the cooling fins and oil coolers clean is just as important as keeping the prefilters (outerwears) clean.

On dirt, we usually lowered air pressure to get more grip on a specific wheel.

Spring stiffness has a lot to do with the G forces in the turns.  The higher the G's, the more spring you need.

[VMS Motorsports]

We use a 50/50 mixture of baby oil and WD40 to keep the mud from sticking. Put it in your garden sprayer and get the insides of the fenders and the leading edges. That and a hour drive home with an old rickety trailer, and the car is pretty much clean by the time we're back to the house. 

[justfreaky]

 I'm going with the lever style proportioning valve

http://www.speedwaymotors.com/p/4839,9_Ractchet-Style-Brake-Proportioning-Valve.html

Push it forward or pull it back; Easier than twisting during race conditions. (A tip from Cy Harvey video.)
I went that route because I think it will work better for me.

 As for the shaker screen; Another way to do it, would be to mount a piece of chain to the top of the screen, Its swinging motion would clear the mud away.

 Softer springs are the way to go on dirt. You will be power sliding the car through the turns, rather than driving through the turns.

 Defineitly go with lower tire pressure.


Steve

 

[MegaMang]

Does anyone racing on dirt cover their belts in the rear cavity with a plastic sleeve to protect the web from the mud off and other harsh compounds?  At least then you could give the car a thorough liberal spraying and wash it up quickly afterwards...

Mike

[justfreaky]

 After some quick searches, I have also found that some are using cooking oil sprays (Pam, or the generic equivilent). Hit up your local Dollar Store and buy it by the case.
 Also the baby oils and WD40 are very popular. Be careful with the WD40 as it may peel up your decals.

Random Thoughts

Steve