Visit The Dirt Forum for More Information

Author Topic:   Lets get this weight % right for once
Steve Dupree
Dirt Freak

Total posts: 316
posted June 15, 2005 07:29 PM  
Ok i want to hear from both sides on rear % verses weight. We have tried both ways and we went and took all the weight off we could and then added to the rear with scales and the car is doing better. Out track is different everynite as most peoples are do to weather and water amount on track. Lets hear will weight will help more on a slick or a tacky or a dry slick or always have rear % up. We really like the way the car is handling but maybe it would be better without the weight that nite but you never know till you come in and then you want know because you cant get back out there and try it. Last week we would have added atleast 50 lbs more and i think i could have finished in the top 4 instead of 6th. With weight added we are 4430 with 48.5 rear we have 200 added to the rear but there are cars that way 3000 so tell us and lets here some input. So what is better more rear % and be 430 lbs over weight or 230 over weight with less rear. We are about 45.6 with out rear weight. Thanks Steve Dupree

iowa_dirt_track_girl
Dirt Freak

Total posts: 461
posted June 15, 2005 07:46 PM  
Well i think I would try a different car all your doing is spinning your wheels here and not gaining much at all.
Have you tryed heavier springs up front and lighter in the back to try to gain some off the corner speed it may feel kind of weird in the corners but if you haev a lot of motor then you can drag them down the straights

neil rucker
Dirt Forum Champ
Total posts: 799
posted June 15, 2005 07:50 PM  
450# is a huge disadvantage! what kind of car are you running? is thre a min. weight rule?

machz18
Dirt Roller

Total posts: 7
posted June 15, 2005 07:51 PM  
do you have a metric car?

Steve Dupree
Dirt Freak

Total posts: 316
posted June 15, 2005 08:09 PM  
Hey 3000 is the min. we run a 75 torino and its really a fast car and going to get a new heart in like two weeks with a little more power. This is what i face we arenot going to change cars we are going to mak this car a no.1 car so forget that. I dont think we are spinning wheels when we have finished in the top 10 every week. We have like 34 cars that run with us so B mains are every week. Letting the best cars starting up front. Last week we started third row in heat and took 4th top 3 went to the a main the we ran the b main took 2nd but could have had 1st anytime but wanted outside. Then we started 7th row outside and finished 6th. So i wouldnt say i am spinning my wheels i want a feel for the weight % and please keep writing. We are setting in 5th at the one track we run with like over 40 different drivers. Two fords and 38 chevys and i am not starting over lol. Please advise more on that 450 difference i may change for this weekend. You still never let me no dirt track girl how you run 35 lbs on the right side and i think you are the only one that i know that does. i am waiting lol

rocket36
Dirt Freak

Total posts: 209
posted June 16, 2005 02:03 AM  
i would run less rear weight on tacky/banked/momentum type tracks and put more rear perctage in the car if you run on slick tracks or tight short cornered tracks where you sort of stop/go all the time.

also visit www.jimmyjudd.com and check out his tech section. there is a really good one in there about weight distribution and transfer writen by scott bloomquist a few years ago.

i would think that you would need anywhere between 50% to 56% rear with a stock type car.

iowa_dirt_track_girl
Dirt Freak

Total posts: 461
posted June 16, 2005 03:56 AM  
OH boy steve this will open up a can of worms here LOL

Ok the deal on running 35lbs on the right side. with our tires 205/70/15 the sidewalls arnt heavy enough to stand the side roll in the corner so we put 35 of air w/o tubes in the tires wich stand the tire up more and keeps the tire on its tread.

As every ones know when your tire rolls in the corner and your tire lays over with out enough air in it you are running on the sidewall of that tire it has a tendance to roll under wich can cause a loose situation kind of like driving down the road on low tires the car feels weird@!
So bye putting 35lbs in it the dirt make on the tire when in the corner is where it needs to be or you could also say the wear mark on the tire is where it needs to be some say you lose a little bite comming off the corner but I say NO cause a taller tire gives you more forward bite

Plus one more thing its way harder to pop a tire with 35 lbs of air in it then it is with a tire that only has 18lbs plus to finsh in the money you first have to finish

Eljojo
Dirt Forum Champ
Total posts: 968
posted June 16, 2005 04:25 AM  
Steve, You know I am an advocate of percentage. I hope that was a typo when you said your car is weighing in at four thousand four hundred and thirty lbs. If you can outrun a decent 3000 lb Chevy with a fourteen hundred lb disadvantage, I need the number for your motor man!
Slick tracks need more %. Stop and Go tracks need more %. Look at who is the fastest...Mods run about 60%. Hooked up on little tires. Better suspension to hook up with and STILL run those kinds of numbers. When you add rear weight, keep an eye on the cross. Keep an eye on the ride height. be sure you still have plenty of travel for your suspension.
I will promise you that you can haul around more weight being hooked up than you will believe. You are close to the front----so keep changing stuff till you get out front and then keep changing stuff till every one swears your cheating...then keep changing stuff.

Racer0
Dirt Maniac

Total posts: 149
posted June 16, 2005 05:41 AM  
I am by no means and expert at this but, I can tell you my car runs better at 3350# with 55% rear than it did at 3000# with 49% rear.

ispin
Dirt Full Roller

Total posts: 48
posted June 16, 2005 06:36 AM  
Dont ever change cars!!!!! Always need more fords out there. The rear % will help the car off the corner mine is 54% and I feel I need more, got a big motor like yours. Look at your pinion angle also for some forward bite

Speedracer92
Dirt Full Roller

Total posts: 70
posted June 16, 2005 07:10 AM  
Steve,
I am kind of in the same situation as you. I run a 77 monte in a hobby stock class. I need to weigh 3600 and i weigh about 3900. My rear percentage is probably around the 46% range too. I have been able to live with it by running no stagger when the track gets dry and this year i am trying the adjustable front sway bar thing and it definitely seems to help keep the car tight. I am mainly loose coming of the corner when it gets dry but on a tacky track the car handles awesome. I already weigh a good 100 pounds or so more than most of the guys out there so I hate to add more weight. I would have to add 2 or 300 hundred pounds to get over 50% rear weight and when I did try more weight, I would lose the right rear even with 35 psi in it. I won the season championship with this car last year and it's doing good again this year so I haven't been very tempted to change anything.

Steve Dupree
Dirt Freak

Total posts: 316
posted June 16, 2005 08:01 AM  
lol yes that was a typo thank goodness. Yea out track is a 5/16 15% banking and looks like a paper clip. I am really thinking of taking it all out for this weekend and see if my driving style has changed that much. We seem to have to change are style every week because of changing conditions so who knows. You guys keep it coming. Congrats speedracer that it amasing to win a championship with a car like that good job. I guess if i take all this weight out and then check all times for the nite maybe i will know if the track is something like we have ran on. Ill check back this afternoon and see what you guys have came up with. Need to go put together this longrod 351 that i am building for the car.

Speedracer92
Dirt Full Roller

Total posts: 70
posted June 16, 2005 08:31 AM  
Thanks! Our track is a high banked 3/8 with pretty big turns so that is probably going to make a difference. The turns aren't very tight. Good luck!

o5racer
Dirt Freak

Total posts: 402
posted June 16, 2005 09:32 AM  
I hate to say it but Iwould be looking into a different car. Mine with me in it is around 50 at 3050# and A friend of mine has a hobby thats 51.5 at 3250. If yours is only carying 48.5 at 3440 you have the world stacked against you. For now though I would look into putting the car on a serious diet. Anything infront of the rearend that can be removed or replaced with something lighter, do it. What kind of car is it anyway? What is your rule on motor placement and firewall gutting?
Nick

97dirt
Dirt Forum Racer

Total posts: 94
posted June 16, 2005 01:43 PM  
Just get a Chevy! lol

beachracing
Dirt Forum Racer

Total posts: 94
posted June 16, 2005 10:25 PM  
Guys, I know Steve, ....and there's no use beating a dead horse, he's stuck with making the Torino work. He's is a pain to get around, but the car does pretty decent for a land barge. I'm one of the many Metrics he has to race, and I've seen his car getting better, and better every week. Curious to see what his little engine change is going to do. Current motor is good on a drier track, and much better running on the high groove where he can keep his momentum up.

Steve Dupree
Dirt Freak

Total posts: 316
posted June 17, 2005 04:35 AM  

 
The car is a 75 torino a starsky and hutch car. This car started out at 3720 at her first race. At our bigger track in elpaso it runs real well but thats along drive and not near the competition as our Las Cruces track. We have about 10 great cars that are in the top 10. Patrick Beach is one of the guys that is a very strong runner but has had alot of bad tranny luck this year. We have one guy at our track that has won 5 out of 6 races and we go by points average on our starts. As far as weight goes i really want to know what would be better or maybe a combination like no weight when tacky and add when dry. I really think lastweek we could have been really cose with a little more weight in the rear but i think i need to see if the car can turn some good laps with out weight like i have seen with weight. Car handles great with or without weight and i can really get on the gas from appex out and really enter hard into the corner and the car runs a good middle to top groove and most of the time thats were the track comes in anyway. We cannot set motor back or move rearend foward we are 114 wheelbase. I think with are longrod motor we will gain what we need to win are first feature and think we might do it without the motor just need in front with the track right. The car has lead many laps and is tough to get around because of size but its also tuff to pass sometimes when working through the field. By all means if i had to do it again and maybe next year i will put a crownvic frontend loose some wheel base and then i know the car will be a champ but thats alot of work for just saying you are the best and out 100.00 payout at the end of the nite. My goal was just to make it a top 5 car and it is that but i want a couple of wins too lol well you guys have a good one and still post weight or no weight and why. Thanks Steve Dupree Oh heres a pic of the boat

juliaferrell
Dirt Freak

Total posts: 370
posted June 17, 2005 06:05 AM  
If you're hung up on a ford build a thunderchicken. Put together properly they are HARD HARD to beat.

STREET16
Dirt Maniac

Total posts: 158
posted June 17, 2005 12:31 PM  
Steve, look at the actual numbers. Your car has 1668.40lbs rear weight. The cars o5racer cited one has 1525lbs rear weight the other has 1673.74lbs rear weight. You probably have enough weight planting the rear tires. Remember, most of these percentages people are quoting are based on 3000lb stockcars.

ispin
Dirt Full Roller

Total posts: 48
posted June 17, 2005 12:40 PM  
Steve we have got to get you into a metric crown vic with a t-bird body. Then watch out you chevys!

Steve Dupree
Dirt Freak

Total posts: 316
posted June 17, 2005 08:31 PM  
Hey street16 you just made are mind up nobody ever talks about how much weight is on the rear compared to the weight of car. More rear weight and car handling good is more traction. Anotherwards if i only have for say 250 horsepower and have 1600 rear weight no matter what % are i have more traction than a car weighing 3000 and only having 1500 rear weight. Now these are the things that we need to touch base on here about this weight i like this it makes sense. I think weight out tomorrow and soften springs a little a be confident just mike be what we are looking for. You have to be convident in what you do or you will go no where. Thanks so much and we will let you know how we do. I am still not running 35lbs. in my tires no matter how heavy i am. I would love to race you dirt track girl at our track and see you run those preasures. Well thanks guys and still want to here more that way we can cover this thing once and for all. Example 3000 lbs. car at 50% 1500lbs. rear weight,3400 lbs. car at 46% rear weight has 1564 to the rear tires. Ok now both have same horsepower but the heavier car still has more weight to the rear wheels there for it has more traction and does not need anymore weight just to have the same %. Now these are good things lets here something on this and use your head please.

Eljojo
Dirt Forum Champ
Total posts: 968
posted June 18, 2005 05:22 AM  
Steve, I like your attitude!
Think in extremes------Honda motorcycle-- 400 lbs
200lb rider
60% rear weight
weight at rear tire = 480 lbs
Dump the throttle and hang on because the front tire is coming off the ground and it's launched.
Chrysler Land yacht
4600 lbs
200 lb driver
10% rear weight
weight at rear tire = 480 lbs
Dump the throttle and get your MasterCard ou you are going to need to buy a new rear tire.
Yake that weight out this weekend and next week end add 100 lbs I think you will see the difference!

Steve Dupree
Dirt Freak

Total posts: 316
posted June 18, 2005 05:52 AM  
Thanks eljojo i am drinking my coffee and thinking and reading between lines here. You are saying i will like my hundred or miss my hundred out of the rear and i think you might me right. Theres one thing i keep remembering is that without weight i remember spinning and getting loose coming off corners and sense i have but weight i havnt had that problem. I have kept the % you talked about at 52.8 left/50.3 to 51.5 cross depending on wheel offsets and stagger. maybe i will just run a little less weight in the heat just because it will still be a little tacky. Either that or add a hydraulic trim switch like i have on my boat that way i could trim that puppy up in the straights and transfer that weight to the rear lol. Well i hope everyone did good that raced lastnite and all that will race tonite. Our goal is to finish the main and load the car at the end of the night and have a great time while we are out there. Going to tech would be fun too but will just have to wait and see.

Steve Dupree
Dirt Freak

Total posts: 316
posted June 21, 2005 05:37 AM  
Well we did a carb. change this week and left the weight and wow what a difference. We started building these 2100 carbs and i finally have it down to a science. We gained 600 rpm over what we have ever run in the past and my answer to the weight % is that if you have the power then run the weight to get % right. If you lack power then run less weight because you will not have the power to spin the tires. We are going to add a little more weight after we win are first main and that will be real soon. We had a heck of a weekend. We had 35 cars at our track in the class we started third row in the heat 8 laps and finished 4th only top 3 went to A-main We were running our smaller tires and was turning more rpms than we ever had and we had to slow down because of a not perfect driveline we had a 82"lr and a 84 1/2 right side. So we had to run the B main so went in and changed tires had the outside front row and knew we had it made so we decided to use second gear and shift to third just to be in front at the first turn and so this up lol. We missed third and the car would not go back into gear. Every car past us and then it finally went back into gear but i was a staight away back from the feild. There where 12 cars in that b main and only 6 were going to the A we mashed the gas and got the field in 2 laps and then got hit in the left front bent tie rod tow was out 3" and we finished 5th in the B dont know how lol. So now we start at the very back of the A-main 25 laps with new tie rod and finished 8th out of 25 cars. What a weekend for a good running car. Goodluck to everyone and have a great week. Steve Dupree

iowa_dirt_track_girl
Dirt Freak

Total posts: 461
posted June 21, 2005 12:49 PM  
Ok now wait a minute here. On this 35 lbs deal this is with 205/70/15 tires not the big tires that most of you guys run with them big tires you have a lot stronger sidewall. So before I get knocked on this again iam just letting you guys know that the pressure is with our tires not yours...

[This message has been edited by iowa_dirt_track_girl (edited June 21, 2005).]

    

Back to the Archives