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missile07
05-14-2012, 08:22 AM
After running Saturday nights heat race I noticed the RF tire had very little to no heat in it at all and the RF shock had 2 inches of travel left in it. The track is a low banked 3/8 mile with fairly decent bite. The car was decent in one turn.... a little tight in but horrible off & too tight in and bad off in the other. Running on American racer tires g-60s. Car just isn't getting over on the right side. Here is what I have:

Chevelle clip GRT

Springs

RF 600
LF 600
RR 175
LR 150 (16inch)

Shocks AFCO non-gas

RF 3-8
LF 5-3
RR 4-4
LR 9-2

Pullbar is a one way spring style with a 1200 spring and 20-22 degrees

Bar Angles

LRU 46 at full drop
LRL 30 at full drop

Cant remember the right side at drop.

Trailing the right side bars 1/4 inch.

Bar lengths are
LRU 16
LRL 12
RRU 16 1/4
RRL 12 1/4

I am running on the short brackets but can run a 13 1/2 or 15 inch bottom bar on both sides if needed.

Q/C with j-bar 1 1/4 above pinion & 6 inches higher on the frame.

Side to side is set to GRT specs.

57 % rear
52.5 % left
49 % cross
25-30 lbs bite

All without me and I am approx. 235 lbs

I dont have the exact scale numbers in front of me but the RF was lower than the LF by about 75 lbs.

Using adjustable uppers and both have right at 12 degrees at ride height and all non friction balljoints.

Any help would be appreciated.

powerslide
05-14-2012, 01:14 PM
Exactly the same problem my friend fought w/ his GRT wouldnt get over on RR/couldnt feel the RR. i was suggesting he either lower the RR upper spring mount or move the spring mount inward but he sold it and got a skyrocket so we never got to work on it.

What fuel cell do you have 32 or 22? Which set of mounting holes? He moved his up and it made entry bad tight.
I would suggest using the longest RRL bar that will help free it up getting in. Maybe to get more roll lower the j-bar on both ends and then make other changes to free up entry as well.

missile07
05-14-2012, 01:31 PM
I have the 22 gal fuel cell. It is pretty high and to the left. I have looked for binding issues and cant find anything wrong.

The j-bar is pretty high in the car so I think I may give that a shot first but I have it where GRT suggest right now.

washeduptoo
05-14-2012, 02:24 PM
Where are your rr bars at ride ht? You can have less fuel to reduce rear percent that would help. AR makes a shorty tire if you think stagger would help. Moving the rr tire out would help also. Just some suggestions, good luck.

dirttrackrocker
05-14-2012, 02:28 PM
I'm having the same problem. Won't get over on the RF. I was told to try a heavier LR spring. And I was running a 200, I'm gonna go up to a 250

JustAddDirt
05-14-2012, 02:29 PM
If you need the car to get over on RR, try moving the fuel cell to the right. All that LR weight is hard to transfer to the RR and RF on a flat track.
Especially if you have 2" of travel left on the RF with a 600# spring.
The weight needs to transfer to right side, but it is hard to do with all that weight of the fuel cell on the LR.
You will still have pleanty of left side with the 235# driver
Do you have a brake floater on the LR, if so put more up angle in it.

Just a thought
you will get all kinds of ideas here.

JustAddDirt
05-14-2012, 02:31 PM
I'm having the same problem. Won't get over on the RF. I was told to try a heavier LR spring. And I was running a 200, I'm gonna go up to a 250

When you do this you will have little to no preload. This will cause the car to fall down till it his the spring on deceleration making entry erratic.
I would not recomment going more than a 200.

dirttrackrocker
05-14-2012, 02:38 PM
Using a 16" spring plus I weigh 260.

missile07
05-14-2012, 02:55 PM
JustADDDirt,

I do have a brake floater on the LR and it is one hole above my LR top bar. I have a 40 lb weight that I was thinkin about putting on above the right rear in front of the fuel cell. High in the car.

I will check the bar angles for sure tonight and post them. I am running right at 2 inches of stagger when its tacky and 1 inch -1 1/2 during the feature

powerslide
05-14-2012, 03:31 PM
I have the 22 gal fuel cell. It is pretty high and to the left. I have looked for binding issues and cant find anything wrong.

The j-bar is pretty high in the car so I think I may give that a shot first but I have it where GRT suggest right now.

i would try moving the cell down and to the right or maybe one at a time. Then also moving the j-bar down to get some roll back along w/ softening the RF spring. W/ the track being flat like mentioned going to be tough to get it over on the RF. Trying to get both ends working together is my opinion.

In refrence to the stiff lr vs the soft lr. Per a very trusted source a stiffer spring will provide more bite/instant traction in the center if off the bars when picking up the gas. Our grt was better w/ a 225 in the lr most of the time. So in short if you cant trail brake i think a stiffer LR is better.

JustAddDirt
05-14-2012, 03:48 PM
JustADDDirt,

I do have a brake floater on the LR and it is one hole above my LR top bar. I have a 40 lb weight that I was thinkin about putting on above the right rear in front of the fuel cell. High in the car.

I will check the bar angles for sure tonight and post them. I am running right at 2 inches of stagger when its tacky and 1 inch -1 1/2 during the feature

I would not go any higher on the floater.
bet if you put a gas shock on the LR that probably make it get over on the RR easier.

missile07
05-14-2012, 03:56 PM
I have several gas shocks to choose from....

Bilstein 8 comp-2reb BSB
Bilstein 5 comp-3reb
Bilstein 9 comp-2reb TSM
AFCO 9-2 200lb psi

Would it be helpful to have both left side shocks gas?

JustAddDirt
05-15-2012, 07:55 AM
since I am soponsored by Bilstein I sould say go with one of those.
I would go with either the 8/2 or 9/2
gas them to 200 if you can, no big deal if you cannot.
this should also help traction a bit as well.

missile07
05-15-2012, 07:59 AM
ok thanks. I will have to look at them to see the psi on each. Should I leave the oil shocks on the other 3 corners?

JustAddDirt
05-15-2012, 09:11 AM
I would leave the other 3 a twin tube, and give it a try.

Egoracing
05-15-2012, 01:05 PM
In reference to going stiffer on the LR, Remember if you are transfering 600 lbs from right to left during cornering and you have a 200 lb spring the chassis is going to raise 3 inches just from weight transfer. If you are running a 150 lb spring the chassis is going to raise 4 inches from transfer. This added lift will also increase the centerline of the chassis which will increase leverage on the suspension AND cause more weight to transfer.

If you want to transfer more to the RF go to a softer spring which will allow the chassis to compress it more which will also allow the LR to extend some more. Just dont go so soft that it bottome out.

This is why so many late models are running a stacked LR, it allows them to get into the 100-150 lb LR spring, couple that to the 250-375 RF and they are going into and thru the corner on the RF while in the gas more.

drtrkr244
05-15-2012, 08:45 PM
First, I would check out the GRT set'up guide. You're pretty far off spring wise.

Second, You are way off on rear stagger.If you have a 60" track width,on a 140' radius turn, the rear stagger should be in the 3 and 3/4 inch range for the feature.A lot of modified drivers make this mistake.The proper stagger for a late model would be in the 4 and 1/2 range with only a 6" wider track width.I know it can be difficult to get with IMCA tires, but get as much as you can.

Third, check your RR tire temp.It should be 5-10 degrees warmer. If the track has moisture, your tires wont even get warm.

Dirtrunner35
05-15-2012, 09:01 PM
If I drive my car in just right , it doesn't roll over very much on the right front. Sounds to me your car is too tight in almost every corner, with a 16'' 150 lb spring, it would have alot of preloaded weight in the spring. Tire pressure, wheel offset ?

drtrkr244
05-15-2012, 09:10 PM
If I drive my car in just right , it doesn't roll over very much on the right front. Sounds to me your car is too tight in almost every corner, with a 16'' 150 lb spring, it would have alot of preloaded weight in the spring. Tire pressure, wheel offset ?

AGREE.......His spring rates versus what GRT suggests, points to too tight.

powerslide
05-16-2012, 10:22 AM
In reference to going stiffer on the LR, Remember if you are transfering 600 lbs from right to left during cornering and you have a 200 lb spring the chassis is going to raise 3 inches just from weight transfer. If you are running a 150 lb spring the chassis is going to raise 4 inches from transfer. This added lift will also increase the centerline of the chassis which will increase leverage on the suspension AND cause more weight to transfer.

If you want to transfer more to the RF go to a softer spring which will allow the chassis to compress it more which will also allow the LR to extend some more. Just dont go so soft that it bottome out.

This is why so many late models are running a stacked LR, it allows them to get into the 100-150 lb LR spring, couple that to the 250-375 RF and they are going into and thru the corner on the RF while in the gas more.

I think what you are saying is the softer spring has more overall drive correct? Especially if you can keep it somewhat on the bars. But i am saying from the point where its laying flat where you are initially picking up the gas it will have more go forward(i know technical term) at this point. That was my understanding from what the great guru told me.

dirttrackrocker
05-16-2012, 11:21 AM
In reference to going stiffer on the LR, Remember if you are transfering 600 lbs from right to left during cornering and you have a 200 lb spring the chassis is going to raise 3 inches just from weight transfer. If you are running a 150 lb spring the chassis is going to raise 4 inches from transfer. This added lift will also increase the centerline of the chassis which will increase leverage on the suspension AND cause more weight to transfer.

If you want to transfer more to the RF go to a softer spring which will allow the chassis to compress it more which will also allow the LR to extend some more. Just dont go so soft that it bottome out.

This is why so many late models are running a stacked LR, it allows them to get into the 100-150 lb LR spring, couple that to the 250-375 RF and they are going into and thru the corner on the RF while in the gas more.


This is making sense to me... I'm gonna give it a try. My problem has been the same as the OP. No heat in RF. I watch the video and all the other cars are doing like you said, riding on the RF like the late models. My car lays over on the RR and the minute I hit a bump or the cushion with the RR it shoves the nose. I softened the RF and stiffened the RR and left the LR alone and cranked more preload into it. I'll see how it works Friday.

drtrkr244
05-16-2012, 02:15 PM
You're shoving the nose because :

1.too much load on RF(increased dynamic wedge)

2.too much LR spring(increased dynamic wedge)

3.wrong shock package.

To copy attitude of lm's you need:

1.RF-high rebound
2,Lr-high compression
3RR-med. rebound

dirttrackrocker
05-16-2012, 02:28 PM
Thats what I have for a shock package now.

drtrkr244
05-16-2012, 02:35 PM
What brand of tire and compound?

dirttrackrocker
05-16-2012, 03:35 PM
Hoosier G60 I run IMCA

drtrkr244
05-16-2012, 08:27 PM
I believe that is a very hard tire.To get a hard tire up to working temp, it has to have weight put on it.

I would mount a 10-20lb piece of lead right behind upper RF shock.I would also move dynamic roll center to right with longer ball joints starting with upper first.

One of the "mysteries" of reading dirt tires is deciding whether it needs more or less weight put on it.

No doubt, tire prep would help if its "legal" at your track. Diagonal grooves and sipes would help also.

dirttrackrocker
05-16-2012, 10:05 PM
Yeah we can sipe and grind, but no grooving. I have the longer Ball joints in. I put a softer spring in the RF and changed the ride heights around a little. I'll see how it works friday.

Dirtrunner35
05-17-2012, 08:06 AM
This is making sense to me... I'm gonna give it a try. My problem has been the same as the OP. No heat in RF. I watch the video and all the other cars are doing like you said, riding on the RF like the late models. My car lays over on the RR and the minute I hit a bump or the cushion with the RR it shoves the nose. I softened the RF and stiffened the RR and left the LR alone and cranked more preload into it. I'll see how it works Friday.

A softer right front spring will not put more heat in it , when you hit a bump or the cushion hit the gas if not the front will come around on you. A softer right front will make the front bite more with the left front, so the car will have more bite in the front and not the rear, making it not so tight ( push ).

What are your tire pressures?? What is your shock compression on right front and rebound on left rear ? Compression on left front and rebound ? Pull the rr back at little to free it up .

dirttrackrocker
05-17-2012, 09:53 AM
The whole front end just seemed like it had no grip. Shocks are 2-7 RF 6-3 LF 4-4 RR Traction shock on LR

Dirtrunner35
05-17-2012, 03:00 PM
Is this a spring behind car? Does the front have less grip because the rear has more ?????? Meaning to tight of a car ?? A push or tight car is because the rear has more bite then the front.

drtrkr244
05-17-2012, 06:55 PM
It appears the car has too much drive.His springs versus what GRT recommends points to being too tight.

I would change springs to what GRT says and/or reduce rear to 55%.

If the RF was still alot cooler than RR(10 plus degrees), put a piece ol lead on RF bar and soften RF spring.

dirttrackrocker
05-18-2012, 09:20 AM
Sorry about the confusion... My car isn't a GRT. Sorry if I hijacked the original posters thread. Just a similar problem...

Dirtrunner35
05-22-2012, 08:59 PM
Friday night my RF tire had no heat at all on a slick track. Entry was ok and a little loose off.

drtrkr244
05-23-2012, 08:17 PM
Were the other cars driving off from you? Sometimes its not possible to get good drive off, if the track is super slick.

Sometimes, you have to treat the gas pedal like it was an egg.

If thats not the case, drop RTT bar, increase 5th coil spring, raise LTT, or lower LBB bar.

Egoracing
05-23-2012, 09:05 PM
A softer right front spring will not put more heat in it , when you hit a bump or the cushion hit the gas if not the front will come around on you. A softer right front will make the front bite more with the left front, so the car will have more bite in the front and not the rear, making it not so tight ( push ).

What are your tire pressures?? What is your shock compression on right front and rebound on left rear ? Compression on left front and rebound ? Pull the rr back at little to free it up .

If the existing RF spring is not allowing weight to transfer to the RF a softer spring that will allow weight to transfer will increase the load and get the tire working which will increase the temp of the tire.

drtrkr244
05-23-2012, 09:25 PM
If the existing RF spring is not allowing weight to transfer to the RF a softer spring that will allow weight to transfer will increase the load and get the tire working which will increase the temp of the tire.

EGO, check out grt's "Tuning car with springs" under Set-up Help.

I'm from "Show-me-state", so I put a car on scales and changed springs, using a ratchet strap to get car to dynamic ride height. You will be amazed at what you find out.

Dirtrunner35
05-23-2012, 09:40 PM
EGO. I wouldn't think a 600 lb spring is to much, he could add more compression to the RF shock and build more heat, but since his car is tight I would think it would be worse if he did that.

My example

Take 4 springs the same height with different lbs , put them on the scales and put a board on all of them. Put 100 lb of weight in the center of the board and see what scale shows the most weight.

I still say your car is too tight IMHO. Fix what the car is doing and worry about the temps later.
Tight/ loose syndrome, after the first turn being tight, he starts to drive different and car gets worse, IMHO.

A tight car is too much traction in the rear compared to the front.

A loose car is too much traction in the front compared to the rear.

Let us know if you race this weekend how it goes. :)

Egoracing
05-24-2012, 07:09 AM
putting weight on a spring on the scale OR strapping the car up with rachet straps will not tell you what is happening during cornering with weight transfer. If a car has a throttle push because the RF is not working when you get the RF working you may actually loose the push.

http://www.integrashocksandsprings.com/general/assets/PDFs/4LinkDirtSuspensionShockTuningGd.pdf

TO MAKE CAR STEER MORE
POSITIVE ON CORNER ENTRY
AND THROTTLE
• Soften right front spring

drtrkr244
05-24-2012, 09:33 PM
Weight transfer is just like changing your cars left and rear percentages.

The only way to change it is by moving lead or components.

Softening Rf spring only cures tight entry while on throttle, ie. decreasing wedge.

Are we to assume you think Joe Garrison doesn't know what hes talking about in his setup info?

Dirtrunner35
05-24-2012, 09:35 PM
A stiffer RF spring will loosen the front and make the push worse , now if the car was loose I would agree and say put a stiffer spring in the RF.

More weight transfer from left to right in either end of a car will loosen that end. I would get a 13 inch Lr spring or lower the cross even more.

What ever changes he does I hope it's better this weekend.

drtrkr244
05-24-2012, 10:08 PM
Thats the fun of dirt racing. Deciding what will make those four little rubber contact patches work better.

Its not always cut and dry.

Knowing when to increase/decrease load on a particular corner is the hard part.

Why is one or more corners of the car not working? Is the load on that tire too much or not enough? Is the spring too stiff thus shearing the contact patch? Is the tire too soft or too hard?

Deciding on whether a tire needs more or less load for a particular track condition is the trickiest part.

leadfoot_35
05-24-2012, 10:41 PM
Thats the fun of dirt racing. Deciding what will make those four little rubber contact patches work better.

Its not always cut and dry.

Knowing when to increase/decrease load on a particular corner is the hard part.

Why is one or more corners of the car not working? Is the load on that tire too much or not enough? Is the spring too stiff thus shearing the contact patch? Is the tire too soft or too hard?

Deciding on whether a tire needs more or less load for a particular track condition is the trickiest part.

I don't mean to high jack the thread but you guys have me thinking. What is your opinions on tire temps? For instance, the LR tire is hotter than the RR. Would you say the RR is working more or less than the LR?

Egoracing
05-25-2012, 06:50 AM
drtrkr244 you are dead on, there are SO many variables. Is it pushing becasue the front is overworked and giving up OR not working enough and the rear is working harder OR the RF or LR has a bent shock which is not allowing the suspension to work, OR the LS weight is so high that is is letting the right side slide and keeping weight from transfering. You have to kind of take what ANYONE tells you (even the chassis mfg) and think about what your car is doing and if the adjustment will make it do what you want it to do.

leadfoot, A tire gets heat due to 2 things, weight load causing it to work and if it is spinning and the friction is causing the heat. Many times a colder tire is that way because it is working better and not spinning, you have to look at the tire wear and see what it is telling you.

Egoracing
05-25-2012, 07:09 AM
Weight transfer is just like changing your cars left and rear percentages.

The only way to change it is by moving lead or components.

Softening Rf spring only cures tight entry while on throttle, ie. decreasing wedge.

Are we to assume you think Joe Garrison doesn't know what hes talking about in his setup info?

There is a reason that the WOO and Lucas drivers are winning races against locals, the books and adjustment guides are 2-3 year old or older info NOT the best but they wont get you into trouble. If you get the first 2 GRT books there is information in them that directly contradict each other. The information on Integras site is the best I have seen for a LONG time.

A softer RF will allow the weight centerline of the chasis to gain leverage on the top of the spring and it will load the spring more it will also allow the LR suspension to extend during weight transfer to the RF(the cars work corner to coner across the chassis not LF to RF and LR to RR). This will allow the car to already be in an attack position when you get onto the gas and it keeps the car from falling off of the bars going into the corner until you pick up the gas.

If the car is going to transfer 800 lbs from LR to RF and you are running a 600 lb RF it is going to compress the spring 1.5 inches. Not alot of movement in the RF and probably not enough to get the spring lower than the weight centerline as it raised during acceleration. NOW same setup with a 200 lb spring is going to compress the spring 4 inches which is going to allow the LR to unload more and raise the weight centerline as the chassis goes up. The added compression and added lift will allow more transfer.

Out your car on scales with a stifff RF and jack up the LR until it adds 5-800 lbs on the RF. Now put a soft one in and jack it up until you transfered the same weight and look how much higher the LR is and how much lower the RF is once you get the weight the same.

missile07
05-25-2012, 08:35 AM
Will transfering my weight over on the right front hurt trying to transfer the weight to the right rear? It doesn't seem to get weight transfer to the right side at all. The car is tight in on throttle and tight in off throttle. Forcing me to stab the brakes to get it to turn and resulting in poor exit forward bite.

We were rained out so I haven't been able to try anything.

Dirtrunner35
05-25-2012, 08:50 AM
Has your car always been like this or is this a different car ?? Since your rained out look for anything binding.

Egoracing
05-25-2012, 09:07 AM
I f it is something new I agree with dirtrunner, something is off. When you are going thru the corner is the LF on the ground and where/when is it off the ground if at all? You need to address the corner just as you drive thru it, entry, middle then exit as correcting one will alot of times fix other areas.

If you are picking up the RF then the only thing loading the RR is the force of weight transfer and the suspension thru the traction device. If you put the car into a state that the lf is unloaded on the scales the RR is also unloaded. (If you put it on a jack and jack it up that is a rigid LF not an unloaded one. We did alot of strapping, and twisitn of a car once to see why we had a push and when we go the car in the on track attitude we found that over 80% of the cars weight was on the LR tire. It was smashed WAY down BUT that is also how it was on the videos of the car. We found some things binding and made a few changes and got the car to 60% weight on the LF and it ran MUCH better.

A stiffer spring will catch more weight decelerating or on the brakes causing the car to naturally want to turn towards that spring. A lot of times if the car was pushing going in BUT had been right before we would add a spring rubber to the LF or go to a stiffer spring. On late models it is not odd to see a 650 LF and a 250 RF now if you figure in the different leverage the mod front has on springs that can be as high as 1100-1200LF and a 450-600RF depending on the suspension.

missile07
05-25-2012, 10:11 AM
The LF does not come off the ground. The car has always been very hit or miss. This is the third year I have ran it and it has always seemed to be tight in.

I tried a straight panhard bar last season a few nights and had really good bite coming off but was still too tight getting in and in the center.

We dont have alot of opportunity to practice so I am looking for ideas I can change at the track.

I started the season out with all GRT specs as far as what is on their website. The numbers you see on the first page are where the car seems to be the best.

washeduptoo
05-25-2012, 11:00 AM
Did you plumb the brakes or some else, had that happen this year, was biasing the brakes the wrong way. Guess you have tried lowering the jbar on frame? Less fuel or rear percent? Sticking the rr out some? A heavier spring in rf, trailing rr more, more stagger, lighter rr spring. Does your rr b/c have more the one hole on the bottom, you could lower it there to loosen if you've tried raisen it up on frame. You've tried most of these, just passing out ideas. If your running a limiter on lr for the drop, you could shorten it. You could put a nail or screw in rf brake line to see if that helps.Best of luck.

missile07
05-25-2012, 11:29 AM
I have tried the following:

-lowered j-bar on frame
-reduced rear percentage from 57.5-58 to 56-56.5
-put a 650 spring in RF

I am trailing 1/4 now how much could I go before it hurts forward bite? I am currently in the bottom hole on the RR birdcage but I can go up more on the chassis.

I run a Afco 90/10 on the top of the rearend and I have seen results where some ppl take it off to loosen it in?

washeduptoo
05-25-2012, 12:42 PM
I would take the 9010 off and see how you like it, alot of guys aren't running them including us. You can run a dummy shock if you want some kind of protection for breakage or cable of some sort. Taking it off, appears to have gave us more bite and loosened it up on entry but we use it on a rough track. More angle in rrb bar will help on entry but I would try the 9010 first to get the feel of it. Best of luck.

Egoracing
05-25-2012, 01:42 PM
90/10 will tighten a car up. I would not go more than a 1/4 inch trail on the RR and you can get a spring rubber or 2 and put them into the LF, if you do not like it then pull them out, we have done it under cautions you just need to make sure that it does not end up high enough in the frame that you can not get to it.

Dirtrunner35
05-25-2012, 03:00 PM
I have tried the following:

-lowered j-bar on frame
-reduced rear percentage from 57.5-58 to 56-56.5
-put a 650 spring in RF

I am trailing 1/4 now how much could I go before it hurts forward bite? I am currently in the bottom hole on the RR birdcage but I can go up more on the chassis.

I run a Afco 90/10 on the top of the rearend and I have seen results where some ppl take it off to loosen it in?

Lowering the j-bar will give you more body roll but less weight transfer in the rear, making the rear tighter and the front looser.

Is your RRL bar level or up hill a little in the bottom hole ?? Go up another hole to try to free it up on entry more.

Has the car always had that 16 inch spring and always tight ?

missile07
05-25-2012, 03:11 PM
I havent tried a lower or higher LF spring yet. Pullbar is barely to LR on the rearend end.

I honestly wonder if my front end roll center is located too much to the right. My upper a-arm angles are about the same when at ride height & from what I can gather if it is too far right then there is not enough leverage to move the weight to the RF.

I am thinking about purchasing the software from Autoware to find out more about my front end. I didnt buy the car new, so I dont know if things were moved.

missile07
05-25-2012, 03:15 PM
no to the 16 inch spring....i have 13 inch springs I can run in its place in most rates but couldnt tell much difference.

Yes to always being tight. Last year we had some sprint car shows at our local track and the car was really good come feature time because of the tightness, but it finally rubbered down.

I would rather the car be good coming off the bottom, so a little tight on the throttle is ok. Just having to use to much rear brake getting in

Dirtrunner35
05-25-2012, 08:21 PM
Stagger ?? Raise the RRL bar up a hole. A friend I know on here has a leaf mod and moved his RR back a 1/2 inch and car was a ton better. And moved it back a little more . His car was always tight.

drtrkr244
05-25-2012, 10:26 PM
GRT recommends 1/2" longer on rt side bars.

Are you tight on or off the gas? That could be why we are giving different answers.

That is one problem with the online adj. guides.

Dirtrunner35
05-27-2012, 06:15 PM
My tire temps after last night
LF- 83 RF- 100-95-100

LR- 120 RR- 136-120

Track was really slick, so I was running the top with my RR in the cushion.

missile07
05-29-2012, 08:42 AM
I think my post was high jacked....

I was able to race this weekend and here is what I done:

-decreased j-bar rake from 6 1/2 to 6
-moved RR lower bar up one hole & increased bar lengths (LRU 16 LRL 13 1/2 RRU 16 3/8 RRL 13 3/4

The car was better getting in but still tight & my drive off the corners was horrible. Honestly I think I would rather have excellent forward and be a little tight. Any ideas?

Dirtrunner35
05-29-2012, 08:54 PM
Did you check your tire temps ? And why did you lengthen your lower bars 1 1/2 ? Does anyone video your racing ?

missile07
05-30-2012, 09:11 AM
This GRT has 3 sets of holes the first set are 12 inch, then 13.5 inch, & 15inch. I was originally running the 12 inch but GRT says to go to the 13.5 inch. Also it was suggested.

powerslide
05-30-2012, 11:02 AM
How did you decrease rake in j-bar? Dropping on frame or raising on pinion? Did you re-center rearend or have a radius mount?

Was the track much different from last time?

I would stick a 550 or even a 500 in the RF if you still have 2inches of travel left and the track is flat. Pull the spring out and put the shock back on and make sure the a-frame will even allow it to travel that far or if something is stopping it.

As a side note if you dont drive the car right and keep it loaded up on the RF the thing is going to push no matter what, 4-4cars aren't very driver friendly. Does your crew tell you that you are driving in to straight or too low?

Edit to add: Spring length doesnt matter unless its coil bound a 16in 200 is the same as a 13in 200 if its on a coilover(which it is). I would put whichever bilstein gas shock has the most gas on the LR. Also pull off the 90-10.

missile07
05-30-2012, 11:37 AM
I dropped the j-bar on the frame with the radius mount & check the squareness of the rearend.

The track was greasy during hot laps, tacky for the heat (slick at bottom), and slick coming out of the turns at the feature.

Track was really close to how it has been all year. I don't have any crew to look at it and give me advice...just going off what I feel on the track and see in photos.

If I take the 90/10 off and take an old shock and drain the oil from it to make a dummy shock would that help keep the rearend end from causing chaos if something breaks?

I do have the option to z-link the RR. What would that do for me?

powerslide
05-30-2012, 12:06 PM
I dropped the j-bar on the frame with the radius mount & check the squareness of the rearend.

The track was greasy during hot laps, tacky for the heat (slick at bottom), and slick coming out of the turns at the feature.

Track was really close to how it has been all year. I don't have any crew to look at it and give me advice...just going off what I feel on the track and see in photos.

If I take the 90/10 off and take an old shock and drain the oil from it to make a dummy shock would that help keep the rearend end from causing chaos if something breaks?

i have never tried that w/ a shock but my understanding is oil helps them cool. If you take the oil out it would be like taking oil out of a motor, it will want to lock up. Maybe someone else can chime in and bust my myth but thats the way i look at it. I would suggest a loose chain. I dont run anything if something breaks its probably spitting the driveshaft out anyway. i know your car is probably an overrail so maybe you can weld something in so the rearend wont roll all the way back if it does break.

missile07
05-30-2012, 12:08 PM
Something I failed to bring up is gear ratio at this track. i am running a 5.67 but some of the other locals are running a 5.83 & up. Would running the higher gear help drag the car down in the turns and help it turn in?

Egoracing
05-30-2012, 02:34 PM
Drilling a shock and letting the oil out is how they used to make a dummy shock, the reason they stopped is the pistion moving back and forth will cause an airflow into and out of the body and it will breath in dust and the added heat will cause it to lock up. The oil is not so much there for lubrication as it is for dampening as it flows thru the piston, the flow is controlled with a valve stack which determines how stiff or soft the shock is.

washeduptoo
05-30-2012, 03:54 PM
When we made our dummy shock, we covered the hole with duct tape and worked fine for us but we only ran it for a few races. We don't use a dummy shock now, we might regret that one night. Good luck

johnny v
05-30-2012, 07:55 PM
Something I failed to bring up is gear ratio at this track. i am running a 5.67 but some of the other locals are running a 5.83 & up. Would running the higher gear help drag the car down in the turns and help it turn in?

higher number is a LOWER gear ratio, and yes.... a lower gear will help you into the corners.....slowing down and turning.... cause engine braking is only on the rear tires......and rear helps you turn...