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Author Topic:   Do we add LR bite or not?
xhubby
Dirt Freak

Total posts: 376
posted June 02, 2004 04:31 PM  
Our DW-8 short 2-link is good entering, but then gets real throttle loose, so the driver has to wait on it to accelerate, then really ease into it. (We have 65lbs of LR bite in it now, with 58.6% rear, & 51.6% left without driver). This is on a semi dry track. When the track gets real dry, should we add more LR bite, & put more front brake into it, or will adding bite make the car too loose getting in? Thanks!!

mod70
unregistered Total posts: 376
posted June 02, 2004 11:25 PM           send a private message to xhubby   Edit/Delete Message   Reply w/QuoteBBBBBB
Could it be a rear end alignment problem? Too much rear steer could be making it loose mid corner. You might try leading the RR some. Adding more split will tend to loosen up the entry some, but if it tightens up at the mid point, you may have an overall gain. The only other thing I could think of is to add angle to both rear bars.
What are you running for a spring arm? Too stiff will loosen up under accel. You may consider droping spring rate, or taking pre-load out of it.

dirtywrench13
Dirt Freak

Total posts: 324
posted June 03, 2004 05:12 AM  
YOU MAY WANT TO RAISE THE RIGHT SIDE OF YOUR PANHARD BAR OR J-BAR,SOUNDS LIKE ITS KICKSTANDING IN MID-CORNER.ADDING ANGLE TO THE LEFT SIDE WILL MAKE IT WORSE,RAISING BOTH SIDES WILL CAUSE IT TO ROLL OVER FASTER.RAISING THE RIGHT SIDE WILL ALLOW THE CAR TO SETTLE OVER BOTH WHEELS AND LET THE SPRINGS AND BARS DO THE WORK. PUTTING SOME STAGGER IN IT MAY ALSO HELP.YOU ARE TRYING TO GET EVEN BITE ACROSS THE REAR IN MID-CORNER.

NJantz
Dirt Forum Champ
Total posts: 755
posted June 03, 2004 06:27 AM  
Adding LR bite will tighten you up on corner exit but loosen the car on entry.

xhubby
Dirt Freak

Total posts: 376
posted June 03, 2004 11:40 AM  
Mod70, we run in a limited mod class, & have to run a spec pullbar. It's a biscuit bar sold by Speedway Motors. We've got it in the bottom hole on the chassis. Rearend is square, LR bar is in the top hole, & RR is in the middle. Running a j-bar, second hole from the bottom on the pinion, & 8" up on the chassis,(recommended by DW).

Dirtywrench13, I thought raising the j-bar on both ends would slow down the roll. Have I been misinformed?

NJantz
Dirt Forum Champ
Total posts: 755
posted June 03, 2004 12:06 PM  
Raising the jbar will raise your roll center which will decrease body roll and loosen you up on entry.

tilley88
Dirt Forum Champ
Total posts: 879
posted June 03, 2004 12:19 PM  
I've got a DW-8 short 2-link and took mine out for the 1st time last Friday. I had it set-up way too tight goin' in. I ended up moving my 50 lb. weight to the left rear and setting it up with 135 lbs. left bite. Had 70# before. Hopefully it'll turn on it's own next time out. I may have to raise my j-bar up on both sides, too. Mine also is 2nd hole from bottom and 8" up on chassis. Let me know how it goes for you this weekend, xhubby. I gotta work, so next weekend is my next try. Good luck.

xhubby
Dirt Freak

Total posts: 376
posted June 03, 2004 01:35 PM  
I guess I need to correct myself a little. When the car was ok in & then throttle loose, we had 45lbs. of LR in it, & the driver (my son) had mostly rear brake in it.
We have to weigh 2550 lbs. in our class, & my kid only weighs 120 soakin wet, so we have had to add about 180lbs, to the car. Talked to another DW driver & he thought we needed to increase our rear spring rates due to all of the weight added to the rear of the car. We had 175-RR, 200-LR. Went to 225-LR, 200-RR, & THEN increased LR bite to 65lbs.
Tilley88, If we ever get to race again, I'll let you know how it worked. Two weeks ago we got the heats in then had to run for cover due to tornadoes. Last week we sat in the pits long enough to get a basket of gizzards from the wienie wagon, then ran for cover again. This weeks forecast for Saturday--- STORMS.

xhubby
Dirt Freak

Total posts: 376
posted June 06, 2004 05:28 PM  
tilley88, we got to get in a whole night of racing this weekend. Changing rear springs, adding lr bite, & moving the brakes to the front seemed to help alot. The track went real dry, so we added a 17lb. chunk of lead to the rr & changed shocks, 30/30 rr, 20/20 lr,20/50 rf, & 30/30 on the lf for the consi,( my kid stepped on his tallywacker while running 2nd in his heat). The car got better, but was loose off. For the a-feature we added another 10-15lbs. of lr bite, but it was still a little loose off. All in all, the car was better, but we're not there yet. Now we need to figure out how to get more forward bite. We're at 58.6% rear w/out the driver. If anybody has any ideas on this area, feel free to share. Good luck tilley88.

tilley88
Dirt Forum Champ
Total posts: 879
posted June 06, 2004 11:04 PM  
How much angle is in your pullbar? How old is the rubber bushing? How old are your tires? How much stagger ya got in the rear? How much angle ya got in the lower links? You need to use an angle finder to get accurate readings. Call Andy @ Dirtworks, he'll give you way different set-up specs than what they have listed on the website. Let me run these numbers by you; left arm angle-15*, right side-10*, pullbar angle-20*. I also fabricated my own plugs because I could'nt get enuff angle with the older style DW plugs. If you have your pullbar in the bottom hole and still can't get enuff angle, you may have to fab a different mount on top the rearend. Hope this helps. BTW, I found my "tight" condition. My new LR slider was in a bind. It should turn left now. Good luck next weekend.

xhubby
Dirt Freak

Total posts: 376
posted June 07, 2004 06:20 PM  
tilley88, Here's what we got.
LR bar-top hole,RR-middle
Pullbar-bottom hole, biscuit-new last season.(new one on the way)
Tires (probably part of our problem)good tread, but old, hard,& glazed. (my x-wife is buying us two new ones this week! LMAO) 1" of stagger in the rear.
I was told Sat. night to take angle out of my pullbar to get more forward bite. This suggestion came from the chassis guy that helped John Satthoff several years ago win two of his Natl. championships. Thats opposite what I've always been told.
I'll check my bar angles tonight to see how close they are to the numbers you mentioned.
Thanks abunch.

xhubby
Dirt Freak

Total posts: 376
posted June 08, 2004 08:23 PM  
tilley88, I just checked my bar angles.
LR-top hole=13 degrees
RR-middle hole=6-7 degrees
pullbar-bottom hole=19-20 degrees
( kind of hard to read with bifocals, LOL)
Would I gain anything by raising the RR bar 1 hole? Thanks.

xhubby
Dirt Freak

Total posts: 376
posted June 11, 2004 05:30 PM  
Tilley88, I talked to gary Clark today. He said I shouldn't need anymore angle in the bars than what the brkts allow. He said that we might want to try running RR bite. I told him that at one time we were around 20lbs. LR bite & the car was throttle tight at the apex, so we took bite out & ended up at about 8lbs. RR bite & the car was a little better. He said we probably didn't go far enough with the RR bite.
How would the car come off the corner with 40-60lbs RR bite? I would think it would be awfully loose. Then again, I was told last weekend, (by an x-Jet Mod tech guy) that you want to run off of the RR on dry tracks. I'm so confused.
Fishin with the grandson is sounding better & better. LOL!

dirtywrench13
Dirt Freak

Total posts: 324
posted June 11, 2004 07:16 PM  
why not just put some stagger in it,using 2-21/2 inches on a d-w seems to work. you may also try this-our d-w 8 has no dampner shock. i rebored the hole and now use it for the top link(pull bar).the front of the pull bar is right behind the trans,and a 400-800 progressive spring.we use 4-z,but the idea is the same.you may want to drop your left trailing arm 1 hole then scale more bite in it,but 8inches up on the left side of the j-bar seems like a lot. i run 4 inches difference between the two sides,most nights.now and then i'll raise it 1/2 to 3/4 of an inch.the short bar is good for smooooth tracks, but iowa gets way too much rain lately.

tilley88
Dirt Forum Champ
Total posts: 879
posted June 12, 2004 09:31 AM  
Was Clark talkin about the new plugs or the old ones? The newer DW plugs have more adjustability(more holes). I really don't have an answer for you on the right side bar angle, as I don't have much experience with mine , yet. I did'nt get to go last nite(still waitin on parts) and tonite looks like rain again. As far as more stagger, that will loosen the car up all the way thru the corner. DW told me to set it up with 30-50# left bite on dry. BTW, fishin is good right now(lol).

JMillerJr76
Dirt Maniac

Total posts: 128
posted June 12, 2004 11:20 AM  
You said that your pull bar is mounted in the bottom hole, I would move it up on the frame a hole or two. Reason being is when you move the bar down on the frame giving you more angle, it will hook the car up quicker but it will lose the bite sooner. It is possible that when you said the car was throttle tight at the apex, the pull bar has the car hooked up, when it is loose off, the bar has lost the bite, then when it hooks up again down the straights the chassis has finally caught up with the momentum of the tires. I would move the pull bar up on the frame if it were my car. We have a DW8 also, and fought about a month with the forward bite problem last season. We bought an X-Factor bar from Jason Gilbert and have tried it in every pull bar hole on the car, and we have found that our car works better with the bar almost level. just my 2cents

xhubby
Dirt Freak

Total posts: 376
posted June 12, 2004 11:36 AM  
Tilley88, I think gary was refering to the stock mounts (3 holes). Our car was built for the short bars, so we don't need plugs. Gary said if anything, to move the right side bar down a hole. The RR bite thing is something we might try in the future if our present setup don't pan out. We put 2 new tires on the back, put a softer biscuit in the pullbar,& raised it up 2 holes on the chassis, & moved it to the left about 1". We also moved some lead around. Don't know if were going to get to try it tonight or not. It's looking like rain again. Thanks for all of the input guys. Have a good weekend.
Gotta go. Our tornado sirens just went off. God I'm getting tired of those things!!!

[This message has been edited by xhubby (edited June 12, 2004).]

[This message has been edited by xhubby (edited June 12, 2004).]

mod66m
Dirt Roller

Total posts: 12
posted June 14, 2004 11:34 AM  
(my x-wife is buying us two new ones this week! LMAO) 1" of stagger in the rear.

I'd like to meet the guy whos ex wife still buys tires for his car.. Your the man.

xhubby
Dirt Freak

Total posts: 376
posted June 14, 2004 04:13 PM  
mod66m, I figured somebody would catch that. LOL. If anybody was driving the car but our son, she wouldn't be so nice. Trust me. After 19 yrs. of paying child support, & 30 yrs. trying to support a racing habit, I'll take what I can get from whoever wants to give it. LOL. Have a good one.

juliaferrell
Dirt Freak

Total posts: 370
posted June 14, 2004 08:56 PM  
If your son is too foot heavy in the corner the lower pullbar angle is going to probably work best. It's alot more forgiving if your peddle happy. I'm not saying he is but I'd rather see a driver go slower and come straight off the corner than to hang the dang things out. It takes a good, good, good, driver to maintain throttle control over a 20 degree pull bar angle.

xhubby
Dirt Freak

Total posts: 376
posted June 16, 2004 05:00 PM  
juliaferrell, Actually, my son is one of the most throttle conscious drivers I've seen in awhile. His first year in a mod, he won 7 A-Features, all on dry slick tracks, & never burnt up a tire.(Unlike his old man who couldn't drive a thirsty horse to water on dry tracks. LOL) That's why I was concerned about the setup being off. When I drove mods, I was told by John Satthoff (Jet Racing) that I had my car set up too aggressively for dry slick, & that the car was trying to bite, but there was no bite to be had, thus breaking the tires loose. I was hoping that someone would verify what I was thinking about the setup being too aggressive. This forum is great. Thanks alot for the input guys.

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