Visit The Dirt Forum for More Information


Note: This is an archived topic. It is read-only.
  The DIRT Forum
  PureStock/Bomber Tech
  Swing arm Z link scale ?

profile | register | preferences | faq | search



This topic was originally posted in this forum: Modified Tech Talk
Author Topic:   Swing arm Z link scale ?
MOD75D
Member
posted April 18, 2004 06:07 PM     Click Here to See the Profile for MOD75D     
Hi guys and gals I just was wondering where would be a good spot to start with my car as far as scaling goes? I have a swing arm Z link both sides. Pro chassis with a metric stub. I just got a set of scales for the first time this weekend and have never done this before. Right now I have 54% left 54% rear and 50% diagnal with 130 lbs. of bite. The track I race at is a 3/8 mile medium banking. Thanks alot for all your help.
MOD75D.


02racing
Member
posted April 18, 2004 07:29 PM     Click Here to See the Profile for 02racing   Click Here to Email 02racing     
This is what we are running on our z-link swingarm. We started out a little less left rear bite and less angle in the left rear swingarm but this is where we are at now. Where on a 3/8 mile high bank track that goes slick. I really like this set-up lot of forward bite and very driveable through the corner. Hope this helps.

LF-850 Left side-53.5%
RF-950 Cross-52.5%
LR-300 Rear-60%
RR-250 Left rear bite-148#
Total weight-2627 with driver
LF-75 Left rear swingarm-18 uphill
RF-76 Left back bar-15 uphill
LR-94 Right rear swingarm-7 uphill
RR-94 Right back bar-12 uphill

LF-6 1/4"
RF-6 1/2"
RR-7"

Shorty bar left side in front of rear second hole from bottom of pinion 4" of rake.

MOD75D
Member
posted April 18, 2004 07:50 PM     Click Here to See the Profile for MOD75D     
Thanks 02. Let me ask you another question. Can you compensate rear percentage with cross? I only have 54% rear with half a tank. Can I just put more cross in it to take compensate for it not being 60%? If not can you please explane why? My car is 2505 lbs. with me in it and I dont want to add weight if I dont have to. Thanks.


02racing
Member
posted April 18, 2004 11:12 PM     Click Here to See the Profile for 02racing   Click Here to Email 02racing     
No I would not compensate rear with cross personally I would not be afraid to hang lead on it if I was you we did the whole stay light deal last year trying to be faster with a light car my personal opionion is the better it handles the faster it will be. We have 200# of lead on our car. I would really try to bring your rear up ours.


02racing
Member
posted April 18, 2004 11:17 PM     Click Here to See the Profile for 02racing   Click Here to Email 02racing     
My numbers are with me in the car I do not know how your scaling your car.


MOD75D
Member
posted April 19, 2004 06:24 AM     Click Here to See the Profile for MOD75D     
I was scaling it with out me in it I was just adding my weight to the total car weight to get the 2500lbs. I will check it with me in it and see what happens. I checked my ride hights and they were off so I reset it and took the weight off that was on the RR and rechecked the scales and now my Left is 55% diag is 54% and 53% rear. with out me in it.


02racing
Member
posted April 19, 2004 07:32 AM     Click Here to See the Profile for 02racing   Click Here to Email 02racing     
Scale it with you in it and the fuel cell full that is where we got ours that way we can take some rear off the car if the track stays tacky by removing some fuel.


MOD75D
Member
posted April 19, 2004 04:06 PM     Click Here to See the Profile for MOD75D     
Will adding fuel take some of the left side away? Or do I need to add weight to the right side? Thanks alot 02. Sorry so many questions.


02racing
Member
posted April 19, 2004 04:20 PM     Click Here to See the Profile for 02racing   Click Here to Email 02racing     
You will probaly need to add lead to the right side depends on your fuel cell if it to the right it will take away some left side but will add to the rear also our lead is mainly to the right side toward the rear high in the chassis. It helps make the car roll over for side bite.


MOD75D
Member
posted April 19, 2004 10:00 PM     Click Here to See the Profile for MOD75D     
Ok.lol. I got the car scaled again with me in it no lead fuel cell full and this is what I have
55%left
49%diag.
56%rear
145lbs of bite
Is this close enough or would you add weight somewhere? The track I race at is always dry slick. Thanks again 02!!


CUSTOMPERFORMANCE
Member
posted April 20, 2004 12:46 AM     Click Here to See the Profile for CUSTOMPERFORMANCE   Click Here to Email CUSTOMPERFORMANCE     
I would add around 120 lbs to the rear to help get the rear % closer to 60%. 56% rear wont be enough in most cases.


CUSTOMPERFORMANCE
Member
posted April 20, 2004 12:50 AM     Click Here to See the Profile for CUSTOMPERFORMANCE   Click Here to Email CUSTOMPERFORMANCE     
My cars regardless of front stub used have been averaging around 2500 lbs with driver(200lb driver), 20 gallons of fuel no lead and 57-58 % rear and with 100-120 lbs added to rear car is 60% or more. Most cars I have built are in the 2250-2300 lbs range without driver.


02racing
Member
posted April 20, 2004 06:31 AM     Click Here to See the Profile for 02racing   Click Here to Email 02racing     
I agree with custom put a 120-150 on the rear and to the right to bring your left side down just a touch. If you are worried about the weight don't the rear is going to help you. My car seems like the more rear we add the better it gets. We started out at about 58% this year. Other than that your numbers look good.


MOD75D
Member
posted April 20, 2004 04:25 PM     Click Here to See the Profile for MOD75D     
Thank you guys very much!! This is not only my first time scaling a car but the first time in a bar car. I am real nervous about what it is going to do compared to the mono leaf car I am used to driving. I just dont want to wreck the car or be in the way. I sold the mono leaf car so theres no going back now lol, Thanks again for all the help. I will add the weight tonight.


02racing
Member
posted April 20, 2004 04:44 PM     Click Here to See the Profile for 02racing   Click Here to Email 02racing     
MOD75D are you running long panhard bar or the shorty bar on the left side.


MOD75D
Member
posted April 20, 2004 07:35 PM     Click Here to See the Profile for MOD75D     
I am running a J bar to the left. I am having problems with this also because my spring on the left rear is hitting the rotor when we push down real hard on the back of the car. I am trying to figure out what to do there also. Was thinking of raising the J bar on the chassis to bring the rear end to the left but dont know if that will work? Thanks 02.


02racing
Member
posted April 20, 2004 09:16 PM     Click Here to See the Profile for 02racing   Click Here to Email 02racing     
MOD75D check your pm


CUSTOMPERFORMANCE
Member
posted April 21, 2004 12:19 AM     Click Here to See the Profile for CUSTOMPERFORMANCE   Click Here to Email CUSTOMPERFORMANCE     
Make sure the rearend is centered in the car per manufacture's measurement. When making any panhard or j bar adjustment you always have to double check the center of the rearend which is usually left rear square with left front. Sometimes when changing the panhard or j bar the center of rear changes not alot but must be double checked.


MOD75D
Member
posted April 22, 2004 05:29 AM     Click Here to See the Profile for MOD75D     
ok I will check that out and see where its at. Thanks Rich.


Back to the Archives