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rubbinsracin
06-15-2010, 12:42 PM
We run a 300# spring on 5th coil and have heard many different people say different things about how much to preload this (from just barely on the spring to a full 1" loaded). Chassis is an '01 shaw with the 5th coil at about 36" and 0.50" preload. The track we race on is a 3/8 decent banked track that stays tacky on most nights.

What do you guys think is the best base setup we can start with?

Also, if it helps we are running a very limited steel head (383 w/ a 4412)

rubbinsracin
06-17-2010, 08:12 PM
id really appreciate any feedback we can get on this guys. we are supposed to go racing tomorrow night....

wwalls77
06-17-2010, 08:28 PM
i dont know if this will help we have a new warrior,but we have almost always run a 350 spring after car has been scaled and all adjustments done,set 5th coil very last,back all the way off and put four rounds in after adjuster touches spring,hope this helps good luck this weekend!:D

mackwrench
06-17-2010, 08:37 PM
Most standard set ups seem to call for 1/4" of preload, 10" spring, wind adjuster down till spring is 9 3/4 with car on wheels (not jack stands) We do ours in the trailer where it's easy to get to. Some shocks have course (Afco) and others have fine (Olins) threads on the body and 4 rounds on one is a lot futher........
I always put some duct tape around the adjuster afterwards.

& 6th coil same way, 1/4" preload.

Its a lot of things put together that make a car work though, I have played with preload from none to 1 inch....I ani't sure driver ever noticed.....I think though you really don't want the spring to become completly unloaded......

MacNoodle
06-17-2010, 09:44 PM
Why do late models run lift bars instead of pullbars? What is there that is being gained over a pullbar? If possible a detailed explaination of on throttle off throttle and traction differences would be greatly appreciated!

leadorfollow
06-18-2010, 07:43 AM
I have always been told 1/4" of preload for the 5th coil. But as was stated previously you can't say just how many turns due to fine or course thread shocks. Afco shocks are 1/8" per turn.

JTSjet
06-18-2010, 08:00 AM
1/4" is pretty common. 1" preload could have some inconsistant effects depending on 5th and 6th coil spring rates, especially when making 5th spring changes. Some folks do this intentionally but just be aware of what's happening.

MasterSbilt_Racer
06-18-2010, 08:54 AM
I always load mine 3/8".

DLM06
06-18-2010, 12:58 PM
Why do late models run lift bars instead of pullbars? What is there that is being gained over a pullbar? If possible a detailed explaination of on throttle off throttle and traction differences would be greatly appreciated!

Good question!

rubbinsracin
06-18-2010, 01:01 PM
well we are preloaded 1/2" not so far off. but i think I'm going to back it off a bit and see what that does for us.

timmayb
06-18-2010, 01:02 PM
LM's front ends are so much better then say a modified that we don't need a stop and go type of rear suspension. Where a mod would need instant traction all the time because of the poor steering, LM's carry a ton more momentum and they don't need all of that instant traction. So the 5th arm works better in almost all cases at least for a 4 bar car.

Same as above. 1/4 inch in most cases.

FlatTire
06-18-2010, 01:39 PM
I have an 02 Shaw and Kevin told me a long time ago to run 1/4" preload on the 5th coil so thats what I've always done! :rolleyes:

dchamp3
06-18-2010, 10:58 PM
1/2 inch preload 350 spring

Pit-Guy
06-19-2010, 10:38 PM
I was told 1/4-1/2" is the correct procedure with or without driver?

JTSjet
06-20-2010, 12:12 PM
It may vary between mfg's. At ride height would probably technically be correct, although i preload w/o driver after setting ride heights. i doubt it would make much difference either way, just keep a consistent procedure.


I was told 1/4-1/2" is the correct procedure with or without driver?

rubbinsracin
06-21-2010, 11:26 PM
well guys thought i would update on how the weekend went. I ended up loading it 1/4'' and during the heat we noticed some fluid dripping under the car. we thought we lost the seal in the tailshaft of the transmission but it turns out the shock on the 5th coil blew out and dumped all of the fluid all over. since we didnt have a spare shock for this application we loaded it down to an inch and went out for the main and ran well. (maybe the best all year) then blew the motor while taking the checkered flag.

Due to the budget it sounds like the season might be over for us unless our backup doesnt take much to freshen up (been sitting for 3 years)