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  #1  
Old 08-13-2000, 07:31 PM
RamHead RamHead is offline
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Say Youall, Ihave been trying to get my modified 78 magnum to accept a left hand turn. This car is a b-body with 41" 1.14" tr bars and 14/15 rear leafs. The car weights in at 3200# wet! Track rule to run 15" x 10"wide towel city recaps. I run 2" offset on each wheel but the RR which has a 3". The car is powered with a 318 with 999 trans. The car does great in hot laps but sets up a push which groes as the track dries.

any suggestions?
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  #2  
Old 08-14-2000, 03:37 AM
340king 340king is offline
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I assume that you have tried different ride heights. You need to look at the height of any weight in the rear of the car also. If it is mounted high it could be causing this problem. Does the rear end have lowering blocks? AFCO has a pretty good disertation on the use of lowering blocks on their website.

You could try a stiffer right rear spring also. I presume the shocks are limited, they too play an important role in handling. Don't be afraid to post any info that may be pertinent here.
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  #3  
Old 08-15-2000, 03:21 AM
Mopar Trac Mopar Trac is offline
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I'm going out on a limb here not knowing the size and banking on your track.
I would guess that you are sprung to stiff on the front I would go down to at least to 1.12 or even 1.00 bars on the front. Another place to check is if teh car has been banged on the right front hard is to check the car for being square. If the right front is pushed ahead the car will do OK on wet tracks and push really bad on a dry one.
Hope this helps

------------------
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  #4  
Old 08-15-2000, 10:57 AM
RamHead RamHead is offline
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The home track is 12 deg. banked 3/8 mile dirt. How much out of square is to much?

RamHead
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  #5  
Old 08-16-2000, 12:40 AM
340king 340king is offline
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Being square is really important. It is the basis of all setups. You need to confirm both horizontal and verticle squareness. An easy way to check for gross squareness is to measure from the center of the lower balljoint on one side to the center of the locator bolt on the leaf spring on the other side. If this is off by much, you have a problem. Be aware that ride height differences and obstacles can cause dificulties in these measurements.

I frequently check the angle the rearend makes with the car by pulling a string line across the right rear and down the car to the front. I record the distance from some refernce point on the frame to the stringline with a certain offset rim. Obviously, a straight rim is required. This is a quick way to check rearend squareness. It can save a lot of time at the track after an altercation.

As for the spring change, with your tracks banking, I would decide if you need to reduce body roll before changing any spring rates. Both of the suggestions made in the previous posts will arrive at the same remedy. One will increase body roll while the other reduces it. Typically, in stock classes there is a need to reduce body roll.

Track composition also has a lot to do with required spring rates. If the track goes real dry during the features, then a softer spring combination may be better. Usually, higher banking requires higher rate springs all around the car. This is to offset the increased normal force imparted by the track banking.
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  #6  
Old 08-16-2000, 02:08 AM
RamHead RamHead is offline
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The Duke Southard approach to finding a bent frame was completed tonight showing 1/4" out. Southard say less than 1/2" is of no major consern. "340" I agree the placement of weight is critical in the rear area. The placement as of now is 6" behind the center of axle on top of the rear frame. There is some weight on the right side just before the rear bumper. The new weight could be added just before the bumper which would be less, but the pendulum effect might offset the gain.
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  #7  
Old 08-16-2000, 02:13 AM
RamHead RamHead is offline
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Also I did change the offset on the right rear but notice some spring interference. I installed a spacer to counter this.
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  #8  
Old 08-16-2000, 02:14 AM
RamHead RamHead is offline
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Also I did change the offset on the right rear but notice some spring interference. I installed a spacer to counter this.
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  #9  
Old 08-22-2000, 04:43 AM
AVENGER29 AVENGER29 is offline
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NOT KNOWING YOUR RULES,I WOULD BE CURIOUS TO KNOW WHAT YOUR PERCENTAGES ARE,LEFT,REAR,BITE,CROSS.
WHAT SPRING RATES ARE YOU USING IN THE REAR,I WAS ALWAYS TOLD TO RUN LARGE BARS IN FRONT.WHEN I WAS READY TO GIVE UP BECAUSE I COULD NEVER TURN, I DROP ALL THE SPRING RATE DOWN,WE RUN ON 1/4 DIRT OVAL,ABOUT 12 TO 14 DEGREES, I WOULD SUGGEST 175LBS ON LEFT AND 150 ON RIGHT,DONT BE AFRAID TO PLAY WITH RIDE HEIGHTS,USE LOWERING BLOCKS.WE HAVE FOUND THAT ABOUT 51 TO 52 CROSS WEIGHT WORKS BEST FOR US,OUR CAR WEIGHTS IN AT 3300 WET.
WE NORMALLY RUN 53 LEFT AND 54 REAR WEIGHT,AND ABOUT 150 TO 175 OF BITE.WE NORMALLY RACE ON A DRY SLICK TRACK.ON MOST NITE WENT I STAY OUT OF TROUBLE WE HAVE LITTLE TO NO PROBLEM GOING TO THE FRONT.DONT BE AFRAID TO GO TO SMALLER DIAMETER BARS UPFRONT.
PS.ONE MORE THING,IF YOU DONT HAVE A SET OF SCALES,FIND SOMEONE WHO DOES,YOU'LL LEARN MORE IN AN EVENING OF MESSING AROUND ON SCALES, THEN YOU PROBABLY LEARN ALL SEASON BY TRIAL & ERROR, GOOD LUCK.
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  #10  
Old 08-23-2000, 12:46 AM
RamHead RamHead is offline
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Avenger, We are presently at 50.1 rear, 54.4 left and 50.2 cross. The car turned very well last race night. The question now is will it repeat. The 999 trans let go the last few laps so we DQed. I have already put my 727 in can't wait for sat. night. The front sway is on with 2" of slop in the adjusting bolts. We don't run a rear sway. The scale's showed the best weight percentage when we equalized the stagger accross the front. The scales are bathroom scales (4 each)with pivot boards. Gives fairly good percentage when set equal distance from tires. The car scaled at the track 3400 at the track, to heavy but turned!

THANKS FOR THE REPLY,

RamHead
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  #11  
Old 08-23-2000, 12:47 AM
RamHead RamHead is offline
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Avenger, We are presently at 50.1 rear, 54.4 left and 50.2 cross. The car turned very well last race night. The question now is will it repeat. The 999 trans let go the last few laps so we DQed. I have already put my 727 in can't wait for sat. night. The front sway is on with 2" of slop in the adjusting bolts. We don't run a rear sway. The scale's showed the best weight percentage when we equalized the stagger accross the front. The scales are bathroom scales (4 each)with pivot boards. Gives fairly good percentage when set equal distance from tires. The car scaled at the track 3400, to heavy, but turned!

THANKS FOR THE REPLY,

RamHead
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  #12  
Old 08-27-2000, 04:31 PM
AVENGER29 AVENGER29 is offline
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we have run the 727 for 3 years without any failure,we run in second gear with a final ratio of 6.57.dont be afraid to go smallerin torsion bars,after changing re-scale car and bring the cross weight back up to original rate. you may also want to go slightly higher and adjust down at the track after youve tried it out.i dont know how knowledgeable you are and down want to seem like im talking down to you.i apologize if im seem to be, im going to assume that you are not that knowledgeable,6 years ago we were pretty successful drag racers,had rude awakening going to oval track,wish someone had been there to help.
if the car is tight,you need to decrease cross weight, if the car is loose you need to increase cross weight. if you have the ability to adjust brakes,ie a balance bar with a crank. loose you want less rear brakes,tight you want more rear brakes. furthermore most track will not allow a brake proportioning valve to the right front, drill the right front brake pads numerous times,or even had a finishing nail inside right front brake hose. on dirt you want to reduce the right front brake effectiveness. remember dont tell anybody, its only cheating if you get caught.
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  #13  
Old 08-27-2000, 04:43 PM
AVENGER29 AVENGER29 is offline
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furthermore dont kidd yourself the guy beside you,in that chevy is cheating in every which way. you just dont know it.on most nite i run against guys that the torque converter has been gutted,there hiding aluminum heads and so forth.i've seem them glue metal shavings like you get from refacing rotors to heads and intakes to hide illegal alloys.amazing what a littl dirt will hide,the new tech director at our track use to be my car owner,very knowledgeable and cheating has been reduced considerably.but still lots of it going on.
ps.what stagger do you run,we run 3 to 4 inches of stagger,neutral in front. however has track goes dry slick,you want to set up more like an asphalt car,and reduced stagger,but dont forget to increase weigth jacks, by reducing stagger you also reduce cross,for dry slick you want less stagger but not necesseraly less cross,should retain same cross in most case.hope im helping,good luck.
luke
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  #14  
Old 08-29-2000, 12:44 AM
RamHead RamHead is offline
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AVENGER29,
Don't worry about talking down. What you might say, that I think I know, will only confer. The car went to the track with 48% cross and turned again . The track stayed damp. We went from a 110" wheel base to a 108" after about 10 laps in the feature. We got caugth in a sandwich in # 4 turn. "ouch"! The main thing is we turned! A new rear spring,check frame, beat out the front and go again! I do feel a little, for the guy that got our rear bumper in his nose. We have a goooood rear bumper! "payback ouch"
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  #15  
Old 08-30-2000, 03:26 AM
AVENGER29 AVENGER29 is offline
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Glad to hear that its working and turning,this year has been the worst for us,can't seem to stay clear of trouble.after loosing the rear bumper numerous time my crewchief got tired of fixing it and build one mean rear bumper.Had to repaint a couple of times but no rebuild lately.lol.
if i can help ask,been there and struggle,didnt know this site existed,wish i had known.
avenger 29
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