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Author Topic:   METRIC CAR ON DRYSLICK TRACK????
STOCK64
Member
posted July 03, 2003 10:26 PM
I'm interested in this one, also. Best luck I ever had with a coil car on dry slick was runnin topside with a big cube motor. Leaf cars kick **** on dry slick if you have to run stock position shocks and springs. Metric cars are touchy, too. Spring pockets are far too close, front and rear. Makes the chassis want to rock too much.


JDF Motorsports
Member
posted July 04, 2003 04:56 PM
that is almost an identical setup as i run with springs and shocks but with 53.3 left and 54.2 rear 49.0 cross it works great on dry slick a little tight on tacky. Wont work if you don't like body roll it rolls really hard. for rear suspension had top mounts 1 1/2 above top of center section with stock metric rubber bushings all others urethane. afco adjustable mounts on lower arms both in lowest hole on tacky then move right one up when track dries out


rico 08
Member
posted July 05, 2003 09:42 AM
I'm going to go out on a limb and suggest a stiffer right front,may seem crazy with a push already BUT is seems like the car is rolling too much with the spring you have on the car now,unloading the left rear and over working the right rear,running a stiffer spring on that corner will require alot less brake there to keep in from making it push worse.


OppendikeRacing29
Member
posted July 05, 2003 04:48 PM
mtrght how much bite do you run?


66jj
Member
posted July 05, 2003 07:11 PM
most imca chassis builders are getting rearends from scs, with mounts on them, is that what you have??

the right top mount is higher than the left about an inch.

IMCA wont allow multiple holes on the rearend.

what chassis do you have??
i guess your track isnt enforcing the wt rule. you might want to add the 100 and get it working with it if your going to go to any big races.. i was at osky 3000 to win thursday and they weighed as does all other big races.

jeff

STOCK64
Member
posted July 06, 2003 07:27 PM
i think you have it backwards... you want the lr to come ahead not the rr. what we do is mount the left lower arm level and the right lower 1" down from level. when the car rolls the right lower will be level (and lengthen) and the left lower will be angled up (and shortend).this will give you rear steer with the lr pulling ahead. do the opposite if you want the opposite effect.

luke

STOCK64
Member
posted July 07, 2003 04:02 PM
stock 64, You are correct. by moving the lr forward you are loosening the car and by moving the rr forward would tighten the car.


OppendikeRacing29
Member
posted July 07, 2003 06:00 PM
right rear foward=tighten
left rear foward=loosen


STOCK64
Member
posted July 07, 2003 06:27 PM
move your right rear foward


mtwrght29
Member
posted July 08, 2003 12:05 AM
here is my take on it. first to answer your question i run 60 lbs. of bite. now on to the the subject of moving the trailing arms. with running urethane or steel bushings on lower arms the rearend isn't going to move forward or rearward unless the bushings are wore out by leaving the left lower at an angle down to rearend and leveling the right lower on dryslick you are keeping the same amount of bite on left and eliminating some bite on right therefor tightening the car when back in the gas due to the right lower not pushing up on chassis because of the angle being removed. last i took the stock mounts on rearend top and drilled a bunch of 1/8 holes to soften it almost acts like a biscuit bar without having one. this setup has worked very well for me may or may not for others. if you try it i hope it helps


mtwrght29
Member
posted July 08, 2003 12:15 AM
i think i should clear something up. the wheelbase will change with body roll but your problem seems to be from apex out. by apex the body should be leveling back out which is where the lower trailing arm angles that i run take effect. these are just my opinions but i will take a car that i can be hard in the gas by corner exit over one that may turn into the corner a little better with no forward bite. i always use a lot of brake to set the car into corner also


STOCK64
Member
posted July 08, 2003 08:49 AM
my car weighs 2675 race ready without me in it. i get about 52% rear if i add 100lbs of lead. alot of it has to do with how far the body and cage are set back. i dont even have an aluminum hood (yet). when its dry it dont matter how much you weight...you need rear to get it to work well on a dr track!

as far as the trailing arms...i like it loose on entry and i use wedge to get out of the corners. thats why i have my lr pulling forward. i may try it the way you guys are doing it though and see what happens.
luke


rocket36
Member
posted July 08, 2003 04:16 PM
i'll add my bit, for what it's worth.
i am at a loss as to why you would want the rear to steer the wrong way. i would tend to think that you would always want rear roll OVERSTEER (rr move backwards/lr forwards) and just tune how much is needed. if you have to make the rear end steer the wrong way i would have thought that maybe there is another problem.
you really need to fix the tight entry first:
make the rear roll over steer slightly
and maybe add a little cross (so i learned with this forum)
once you've fixed the entry, if its still loose coming off:
increase angle in right top rod
lower panhard bar (roll centre) or put more angle in it

see how you go but work on one problem at a time and check for suspension binds and regularly check front end alignment.

from my experience racing stock cars, make sure all the suspension bushings are rubber, not urethene, alloy, bronze etc. as most stock suspensions have to twist up as they go through there full movement.

mtwrght29
Member
posted July 08, 2003 11:22 PM
my car with about 375 lbs. of lead and me weight 3050. the cage is sit way back and we run aluminum bodies so i lost some more weight there. as far as total weight i would personally add more to get the bite you need for dryslick. i firmly believe that probably 90% of cars on dirt have way more motor than they are putting on the ground. all of your competitors are on the same carb as you so the game becomes who can use more of it.this setup will be tight on entry especially when the track has some moisture because it rolls so hard. honestly my car carries the left front tire. you will need a lot of brake to get it to turn into the corner. as far as stagger i run inch and half on tacky and half to none depending on how dry the track gets the more rear stagger you have the looser exit will be. now for moving the rear either way. this is something you cannot prevent but i like to use the rear suspension to get optimum bite not to turn the car. i've never had a problem with urethane bushings as long as they are kept clean. sorry about the length but i have one more thing. my motor is just a modest 355 but the car hooked so well that on a 1/4 mile relatively flat track running 7.35 gear turn 6800-7100 rpm depending on track conditions and getting twice as many nights out of tires as most everyone else


ss#4
Member
posted July 09, 2003 03:29 PM
Stockcar5,

Question: What are your ride heights relative to the frame in front of rear and behind the front tires to the ground? This will take into account different tire diameter/heights.

also what is the definition of "bite" is everyone refering to the difference between the weight at the rear tires. Meaning the RR has 60#s more than the LR? Is Split the samething just on the front? Sorry for the dumb questions just trying to follow along and learn.

mtwrght29
Member
posted July 11, 2003 10:53 AM
my ride heights are front lower a arms level and approx 7 across the back never really measured the backs to be honest just what looks right and always set front by a arms. bite is the weight difference of rear tires left one is always the one that is heavy. split is the same as bite.


d4490
Member
posted July 15, 2003 09:36 AM
mtwrght29, you say that you carry your left front. Do you have a panhard bar on this car? Any other suspension piece other than the stock 4-link setup? How much do you carry the left front.


carboy34h
Member
posted July 16, 2003 11:13 PM
here is what i run in my imca stock car dont know of the weights or ride heights but did have same problem with burning the rr tire off and gaining 8lbs air pressure
Springs fronts afco and rear blue coil
lf #1000 Tire pressures
rf #1000 lf 13lbs
lr #200 rf 17lbs
rr #175 lr 8lbs
Shocks all afco rr 10
lf 1275
rf 1276
lr 1294
rr 1293-5
Wheel offsets
lf 2"
rf 1"
lr 2"
rr 4"

the car weighs 3200lbs the weight being 150lbs middle of car above rear end and 50lbs over on the right side and fuel cell plumb full. the setup man told me i was working the lr to much and rr wasnt doing nothing so he put lead in the car to make weight plus to pin the rr tire down to make it do some of the work. well by god its workin now i fade back alittle bit but by the end of the race i'm up in the top 5.

this is my set up that works for me on dry slick if there is any thing else i could do to tweek it alittle bit to be better ideas are welcome

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