LR setup

[rubbinsracin]

I have been thinking about a LR setup that we have not tried before. we have thought about running a dummy shock (0comp-0reb) behind LR with a spring and running a gas traction shock in front (6comp-0Reb) with 125psi. We run on a 3/8th mile mild banked track that stays hooked up most of the time. or would it be better to run the traction shock with a 7c-3r or a straight 4?

[xray]

no reb at all = no good

[jedclampit]

Why do you want to do this?

[rubbinsracin]

I kinda figured no rebound would be a bad thing. lol. im just a pretty big guy. around 300lbs and the car doesnt like to get up on the bars with me in it so i have thought about trying it. i think we would run a 1394 with the gas traction shock(6c-0r) with about 125psi. were just looking to try different things to see what happens.

[AmickRacing]

If there's plenty of traction in the track, sometimes a flatter car that's not up on the bars can be faster. There's even some guys running the shock/spring in front of the LR when it's tacky and fast and doing pretty decent.

[lovinlatemodels]

If your running a 6/0 on the front of the rear with 125 psi of gas instead of a 4 valve in the back try a 6/2 or even a 8/2 with the spring along with the 6/0 on the front. Your were asking before about LS % and trying to get the car up on the bars what do the other 3 corners have for shocks and do you have your car rocked up on the left side or is your car sitting flat with you in it.

[rubbinsracin]

The car has always ran well in the past but this is my first year in this chassis. ran an 01 shaw before we got this 04 shaw this car was ran with a driver that was about 160 and i am about 290 so we were struggling with getting the car up on the bars because our LS% was like 60-61% with me in it. we took some lead that was just behind the LR tire on the down rail for the fuel cell and moved the fuel cell over so it is center over the rearend so as burnoff occurs it occurs evenly across the rear and set the wedge to about 120 lbs with me in it. which got our LS% down to like 54% after we did this the car was much much better the next week out(i was actually passing people in my second week in a LM)

i guess we are just looking for a little more side bite and bite coming off the corners. on film it looks like what is separating me from the back of the average guys to the front of the average guys. as a first year driver in this class(ran IMCA hobby and stock cars, i have helped on LM for about 5 years), and running a steel head motor(we have to weigh 250lbs more than the guys up front running a 602)

[lovinlatemodels]

Glad to hear the fuel cell and lead change helped you might need to give some more info on your set up shocks springs and even bar location to work out some problems. Even you J bar location can help alot. What worked for a 160 lb driver might not work for you. You might need a different spring package.

[rubbinsracin]

yeah. we are learning what worked in the past might not work for me. ill try to give you some more info on my setup too

LF is a 500 with old style afco DA set at straight 5
RF is a 375 with old style afco DA set at 4c/6r
LR is a 250 with 1397c-3r mounted behind
RR is a 225 with 1394 mounted adhead

5th is @ 35" with a 1373 with 300lb
6th has 400 lbs spring

caster&Camber are set to our shaw sheets we got from Kevin.
front stagger is about 1/2"
Rear stagger is about 5 1/2"
pressures are LF 10 RF 12
LR 6 RR 10

Jbar is mounted just below the centerline of the pinion and about 9 3/4 rake one the frame side

LU mounted in 2nd hold from top on frame (can go one hole up) about 22*
LL is about 5* uphill to frame (can increase it one hole up)
RU is about 19* uphill to frame (can go up or down)
RL is supposed to be set to level with ride height in lower hole (right from kevin shaw)

54% Left
56% Rear
120ish lbs wedge

[29racin]

set up sounds good . I run same thing on 07 shaw with the exeption of shock settings. have same problem i am gonna try 2 stage spring on rf and see what happens. . i am tight on throttle entry and loose off trottle middle but ok on exit. wht does the lr shock sping front or rear do? any other suggestions would be appreciated.

[rubbinsracin]

im good on entry and middle but need some drive off. i going to try the setup i have now for one more week and see if we can just do some tuning to develop some more drive on exit. if i cant get to much more drive with tuning, im going to try a 425lb LF spring. i know it will free me up on entry and in the middle but i think i can manage that if i can get some more forward drive off.

@29racin - not sure what you are asking, but i think you are referring to what i originally asked about. by mounting the gas pop up shock in front with the regular shock/spring combo you have on the car you basically help stay up on the bars off throttle and creates more drive if i understand correctly.

can someone chime in with some more knowledge???, preferably someone who runs a dual LR shock setup and let us know what works for them. both 29racin and I run big 3/8 an 1/2 tracks and pretty similar chassis, so the info we can get should pretty much work well for both of us.

[lovinlatemodels]

Are you running a traction shock on the LR along with the 7/3 shock on the spring and if so what is it. You could try a softer LR spring the add preload on that spring can help lift the LR. Also with that much rear weight you could also move your lift bar back some that also on traction coming off the corner.

[rubbinsracin]

no currently we are running only the 7/3 with a 250 spring mounted behind axle. should we leave everything the way it is and just put a traction shock in front? we start the race with about 56% rear and finish wiht about 54% with burnoff. we are trying to be setup for the end of the race.

[jedclampit]

Some things I would try:
-raise your ballast if you can
-More bar angle in the lr rods upper and lower @ frame
-indexing lr upper rod @ birdcage
-rock up the left side of car 4-6 turns
-more lr (275-300)spring
-less rr spring (200)

more rf spring....not sure what the norm is for those cars 375 sounds light with your engine

[rubbinsracin]

- ballast is as high as it can go.
- LR Top bar is in the second hole from top on frame for heat and then for feature we move it to the top hole. LR lower might be able to go up one hole
- LR upper rod is all the way down on the birdcage
- i dont want to rock the car up unless its a last option because i dont want to mess the ride heights all up
- we have never went higher than a 250 on the LR...maybe worth a shot but i would have to go out and buy a spring or two
- might try the 200 on the RR. that would for sure allow the car to move over quicker.
- might try going up to a 425 on the RF. that would for sure loosen entry and middle but provide more drive off the corner.