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Author Topic:   Hot right rear tire
Steve Dupree
Dirt Freak

Total posts: 316
posted May 22, 2005 06:24 PM  
Hey guys we are getting close with all your help but we need a little info. Lastnite we had a hot rr with a cold lr. I know we could have been faster with both equal yes or no. We ran as fast as leaders just didnt get the best starting position and stayed at bottom of track too long. We were running a LR 2 off 82 rollout and a 84 3/8 rr with 48.3% rear weight in our stock class. 2 barral 9.5 cast iron intake dot tires 7" wheels. 3430 weight to get 48.3. Air preasure was lr15 rr 18 Car was great but why so much difference in tire heat and that should mean more faster times with equal tire heats. Input please. Springs lr 258 rr 233 We are the best we have been but need to be better any help would be appreciated. Thanks guys and gals

sideways
Dirt Forum Champ
Total posts: 715
posted May 22, 2005 08:01 PM  
RR hot your loose.Can ya get the rear % up.

iowa_dirt_track_girl
Dirt Freak

Total posts: 461
posted May 22, 2005 08:06 PM  
you could be loose but your just getting to much drive off the right rear so you need to get more off your left so you could do a few things such as add more spring rate to your left rear OR add more weight to the left rear take stagger out of the car would do it also

STREET16
Dirt Maniac

Total posts: 158
posted May 22, 2005 08:36 PM  
By 2 off, do you mean a 2" back spacing on the left rear? If so, go to a 3" or 4" back spacing. Basically, move the left rear in and/or the right rear out.

Steve Dupree
Dirt Freak

Total posts: 316
posted May 23, 2005 08:22 AM  
Well i could have been higher on the track i was running a line a little lower than i should have. As far as loose the car really felt ok this car you really have to watch it or it will push. We ran a 3" stagger in the heat with a 4" offset on the left and a 5" on the right and it handled ok. I thought moving the left rear is what you wanted to do as the track went dryslick. I still am lost on this offset stuff to a point it is not sinking in this darn brain. I could add a little more weight but we are 400 over what we have to weigh. I relize what happens to the car on scales when changing heights and offsets and what it does to cross weight but i think i would have been faster if both tires were a little closer in heat. I thought you really want to drive off the left rear in the main event when the track goes dryslick. Well Keep it coming in maybe i will get something that hits me lol. I can go straight up in the rear but need to break to get the car to go into the corner alot or drive it in really hard but maybe i should also i could have been easier on the throttle control the other nite but i wasnt spinning or loose coming out.

racer17j
Dirt Forum Champ
Total posts: 5390
posted May 23, 2005 08:10 PM  
Hey racer17 did you mean to say left rear. I think what has cunfused me is someone may say something but mean something else or i take it wrong. I have read in the modified books that you move the rearend or right tire out for a wet track and then you move the left tire out and the right in for a dry track.So for a dry track in general do you move the left in under the car or out further away from the car. I would actually think you move the left rear tire in because it puts more weight on the left rear tire so maybe we are getting close on me understanding this. I am going to go read that darn book one more time for the 100 time lol Please respond Thanks Steve Dupree ............ I call a offset like a 2" will set the tire out more than a say 4" offset will set the tire in. So dry do you want the left in or out.I mean if you pull it in on the left are you tighten the car. Thanks Guys and Gals i know i will get this.....Maybe lol

Flanndad
Dirt Freak

Total posts: 255
posted May 24, 2005 05:11 AM  
Dry/Slick move tires to the left.
Wet/tacky move tires to the right.
And that's the rear tires.

Dry/Slick less to no stagger, maybe even reverse
Wet/Tacky more stagger

That's the understanding I always had.

Steve Dupree
Dirt Freak

Total posts: 316
posted May 24, 2005 08:08 AM  
Thats what i understand did i read racers17 post wrong. "yes you are right on a dry track you want to tuck that lr in as far as you can and take some stagger"

iowa_dirt_track_girl
Dirt Freak

Total posts: 461
posted May 24, 2005 12:52 PM  
we run the same setup for heat and feature just fight a push for the heat unless its a big race where you have to finish good in the heat then we may adjust it a little

racer17j
Dirt Forum Champ
Total posts: 5390
posted May 24, 2005 06:04 PM  
lol racer17 we get that all the time and i understand. We have done it too lol. Fine tunning this car is working we turned are most consistant times this last weekend with the weights i gave you. I still have one thing that confuses me If you tuck the wheel in you add weight to that corner i would think it would get more out of that tire why doesnt it. I like the times we ran along with everyone elses on sat. but i didnt like the difference in the heat of tires. Maybe i just had to much stagger along with moving tire out on the left. This car is a 114 inch wheel base and we need to be fast to keep up with these 108 metrics. I am going to get this why if more weight is on wheel it doesnt have more traction. Drop this rearend on my head i have lost it lol It just dont make sense yet in my head but who cares as long as i understand and it works. Why did i build a dump truck.

iowa_dirt_track_girl
Dirt Freak

Total posts: 461
posted May 24, 2005 07:55 PM  
Steve when you move a offset think of it as a teater toter. The closer you move the tire to the spring the quicker the spring reacts so draw a line like a teater totter now move you weight close to the center see how hard it is to push it down now move it away and then see how easy it is to push it down
Hope thatit makes since
O bye the way is your car X underneath

beachracing
Dirt Forum Racer

Total posts: 94
posted May 24, 2005 09:16 PM  
It doesn't need X bracing, it's a fricken tank! Trust me, I have to pass............or attempt to pass him every weekend! To loosen the car you tuck the left rear end, as well to push the right rear out. Every car is different, every driver is different. Some like it a bit loose, some like it tight.

beachracing
Dirt Forum Racer

Total posts: 94
posted May 24, 2005 09:41 PM  
The track that we race on can be a very deceiving surface. Set up wise, first part of the season we will have wet/tacky heats, but on occasion we get a few spots in the turns where it glazes. Some nights the track can be well packed in tacky, but can slick up in places towards the end of our 25 lap features. Other nights, we fight to find sticky lines, in my case it consist of taking the car almost over the backside of the backstretch which is where the water truck dumps water for dust control, or way down on the aprons, and the apex of the turns.

iowa_dirt_track_girl
Dirt Freak

Total posts: 461
posted May 24, 2005 10:49 PM  
Listen these cars have to be X braced to work right ( now thats really going to start something now)
If your car is not X underneath the four corners wont work like they need to.

One more thing on offsets is that when you change stagger in the car that changes all four corners when you cahnge offset it changes that part of the car

Steve Dupree
Dirt Freak

Total posts: 316
posted May 25, 2005 08:03 AM  
Thats funny race track girl laying in bed lastnite thats excactly what i was thinking about was a teeter totter. I think i might acually understand this a little better. Abut that X bracing cant i quit adding weight please lol. Poor little 351w is doing all it can. Its just like the little train... i think i can, i think i can, i no i can, i no i can. Well maybe i can lol Be good all and thanks

CLBaker25
Dirt Maniac

Total posts: 193
posted May 25, 2005 02:46 PM  
Is there any way that you can lower your overall weight of the car?

I think that would be the #1 thing I would work on. If your car is 400# over the weight limit you are not going to be nearly as fast as you could be. Especially when we are talking about nearly 3500 pounds. Get that car down to around 3200 and you will be alot faster. If you car is loose just take a little bit of that stagger out. You have 2 3/8 inch of stagger. Unless you are running a 4 bar modified you shouldn't need that much.

Steve Dupree
Dirt Freak

Total posts: 316
posted May 25, 2005 05:37 PM  
Well we have tried lowering that weight and are rear % falls way off. I thought when we did that at first we were on to something but not really so it seems. I went back to adding weight just in the rear and getting that rear % up with what racer17 has told me and gave it an honest chance and really i like it. We wer in alot more traffic than the leaders and turned the same time. We have 48.1 rear % with the weight we have and full of fuel with driver at 3429 total weight. We run a 12 gl. fuel cell and have a 120lbs in lead on the rear. 120 + 50 fuel we could nock off 170 but end up with about 45.5 rear %. Lets hear a little more on this thought i am still open to ideas but times and getting to the front is what i will end up running. Of course we are building a better motor with help from someone here named ford5 and cant wait to get er done. Keep er coming i am listen.

Donald g man
Dirt Roller

Total posts: 14
posted May 25, 2005 09:22 PM  
Hey Steve, thought you pulled the anchor up on that boat! Would it be legal to place the motor farther back? If the metrics get 94" then so should you. The rules say "metrics" not "gm metrics", I am sure there are plenty of metric bolts on that car. Ford is made the world over in "metric diminsions", hammer that fire wall and get-r-dun.#71

Steve Dupree
Dirt Freak

Total posts: 316
posted May 26, 2005 05:08 AM  
Hey there Mr. gorham how are things going. Congrats to your son and sorry we cant make it to graduation but we will try to get over there and run with you guys soon. Yea they said no on the motor but when i put this new one in and make some welded mounts it might just get put back a little my measuring can get pretty confusing when building something lol The car has really been doing good in cruces just need a good start. Well take care and talk at you soon hope you enjoy this site there are alot of nice racers here. Steve Dupree

CLBaker25
Dirt Maniac

Total posts: 193
posted May 26, 2005 07:17 AM  
Do you have the added weight right on the bumper? I would put it clear back there. I know that there is the whole swing weight debate, but with less than 50% rear it is not an issue in my opinion.

What front springs are you running? I would think if you went with a 1000/1200 in the front and a 225/200 in the rear it should be able to get some forward bite. If you car is loose in the middle with this setup I would go to 1100/1200 front springs. I think that you can manage your your low rear by going stiffer in the front and softer in the rear.

Steve Dupree
Dirt Freak

Total posts: 316
posted May 26, 2005 06:15 PM  
Hey baker we are right in that neighborhood on the spring rates. I believe the right front is 1148 and the left front 1078 as far as rear goes we can go from 158lbs. up to 258 in about 25 lbs increments meaning left side stiffer. Yes the weight is back and if i try this other 25lb. weight it going right on bumper it puts the rear % at 49% with full of fuel. I dont think i should add it till the main because we usually are still a little tacky in the heats. So if you saw better times with the weight would you try to use it and get car where you like. I really think it needs the weight in the rear i think with our motors we should atleast have 48% and with no weight i was like at 45% and havnt seen times like these during race conditions. I have on pratice days but i could drive anywhere on the track. Big difference lol

CLBaker25
Dirt Maniac

Total posts: 193
posted May 27, 2005 07:38 AM  
I would still take some stagger out and lower your left front spring rate to a 1,000. The added split spring split should tighten the car on exit. I still think that your rear springs are too high. I would go with a 225/200 in the rear and lower that left front spring. (These are just suggestions from what has worked for us and this is also without being at your track and seeing how your car is actually behaving and what your driving style is. If you are getting faster with the changes that you are making I would keep with it. I think that lowering your right rear spring rate would help the car be faster. I am not sure how it would affect your tire temps. I have found on our car that sometime a hotter right rear is faster as long as you are not cooking the right rear tire. On our car our hottest tire is usually the right rear then the right front then the left rear and finally the left front.) Good Luck

Busch
Dirt Full Roller

Total posts: 46
posted May 27, 2005 08:58 AM  
I dont know what kind of movement or roll you have in yor car but when we were doing exactly what you are doing we found that the car wasnt rolling over on the rf it ended up being a bushing that had bound up. Also with some of the others I feel your rear percentage needs to come up. It would be well worth your time to hang some lead up high in the car and close to over the rear end make sure that you can easily move it left or right in the car and higher and lower approx 6 to 8 inches. If you start hanging weight too far back or too low the weight wont transfer properly and will also cause poor handling or tires to heat improperly. Wish you the best from another FORD guy.

Steve Dupree
Dirt Freak

Total posts: 316
posted May 27, 2005 07:28 PM  
Busch let me think on this one a little i will tell you what i did lastyear to cure something. This car used to ruin a front right tire in 2 races it pushed bad. Another ford owner gave me some advice. We moved the right torsion bar foward but the washer is flat on front frame we run a rubber up front of the bar but took it out in the rear. I have thought several times of turning that washer were the curved side was to the hole. We double nut the front so no problem of coming loose if we did this bu i think it might fre it up a little. It doesnt pop or anything when jacking up corners but it has always bothered me. But that move in are car made the tire start lasting and to start handling. So actually our wheelbase is longer on the right side than the left by like a 1/2 to 3/4 of a inch. Did you ever have this problem. Our track is a 5/16 paperclip we turn around mid 19s when the track is dryslick and that means everyone not just us. Dont think with the weight we can ever compete on a tacky track with this car but on a dryslick i think we can and will lol. Well thanks for reply sure hope this rain holds out tomorrow it got us tonite at El Paso. Thanks steve

    

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