Tech Talk

it just depends on what the rule is but yes the rules are vague in some areas. shoot me an email goinfast98rt@aol.com thanks

Ok,got it all done today,race is tomorrow.

Went with 175 in both fronts,bumped the RF,have a spring rubber if LF
Went with 150 in both rears,bumped the LR,have a spring rubber in the RR

Bar unhooked(for scaling purposes)heres the %'s(with driver)

C-49.6
L-56.1
R-45.6

TOTAL WEIGHT-2336

LR Travel before hitting bump(with driver in car)is 1/2"
RF Travel before hitting bump is 2"

used to run a 1 5/16 aftermarket bar out of summit

Rock, Would like your opinion on a set-up for a 3/8 mile 10 degree banked track, I am running a template body late model, it is a Cra car. We have had a tight issue all year from the center out, We have been running 200lb springs on the front with bumps, a 3 piece 1 3/8" sway bar, 250lb LR spring and 550 to a 650lb RR spring. I run the panhard bar at 10 1/2" on the rearend and 9" on the frame. Cross with the driver 55%, rear weight is 50.2% full of fuel and 58% left. I think were missing something with the bump loads. Should the RF hit first. Thanks

i believe the first thing he will tell you is DONT BUMP THE LEFT FRONT

I would agree with what 83815 said about what he would say. We run the same kind of bump setup, but we are running 52.5 cross and about 1-1/2 higher on both sides on the j-bar. The left rear you have is higher than what we run also.

From my experience the cross and lr spring will will change off the corner a lot more than the center of the corner. Where the j-bar will loosen the car both center and off.

I'm not rock, but hope it helps

Quote posted by jtofast:Rock, Would like your opinion on a set-up for a 3/8 mile 10 degree banked track, I am running a template body late model, it is a Cra car. We have had a tight issue all year from the center out, We have been running 200lb springs on the front with bumps, a 3 piece 1 3/8" sway bar, 250lb LR spring and 550 to a 650lb RR spring. I run the panhard bar at 10 1/2" on the rear end and 9" on the frame. Cross with the driver 55%, rear weight is 50.2% full of fuel and 58% left. I think were missing something with the bump loads. Should the RF hit first. Thanks
First off, 83815 is correct.
I'm going to try and answer this, I'm not good at these type's of questions, mainly because I type with one finger and it takes me awhile and I tend to lose my trend of thought.
There is so much on this site about this very same question and my answer is for the most part always the same.
I talked to a person today about the same thing, not the same question but it kinda got to this just in talking about Locker springs in general.
I could retire if I received a nickle for every time I have said this, put 4 175lb springs in the car bump stop the RF & LR.
Now I will try to explain why.
I'll go to the back first you put a heavy RR spring in the car, now you have to lower the rear roll center because the big RR will make the car loose so what you end up with is the setup fighting each other and now you have to run to much cross to keep the car under control some what, here's what I would do.
1. put in 4 175lb spgs.
2. bump stop the RF & LR only.
3. put in a bigger sway bar maybe a 1/5/8" preload it two turns at the track we don't care how that effects the cross, cross in this case is just a number.
4. start out with 49% static cross.
5. make sure your camber and caster split is correct (caster split should be around 4deg.) 1LF & 4 to 5RF.
6. the reason for the pair of 175's in the back (and not a heavy RR) is so the LR bump stop can be effective and you will be able to run much less cross so the car will turn on a dime, the heavy RR spring keeps the back of the chassis from getting onto the LR bump stop thus making it worthless, and now you will need the cross and that is a bad thing, I guess the bottom line is you want all four tires to be happy, happy is fast...
I guess I should have mentioned this first, for the front of the car the bump stops main purpose is to limit travel so you can run very soft front springs,
the bonus to the RF bump stop is that it also makes the car turn by planting that tire to the track better, and some people can't understand the concept of that so I will try to explain and again I have said this many times also, go out to your shop/garage wherever you work on the car, put a rag on the floor put a 2lb hung of something on the rag now grab the rag and pull it 2ft. its pretty easy, now take the same rag put 20lbs on it now grab the rag and pull it 2ft. it will be much harder to move THATS BECAUSE IT IS PLANTED MUCH HARDER TO THE FLOOR, the same concept with the RF bump stop and the RF tires grip.
I'm sure I missed something so just post any questions you may have after reading this, I'll be happy to try and explain anything in a different way to make it easier to understand, I know many of these things are difficult to understand, I'm not even sure I understand it. LOL
Like I said I'm not good at this so I know it's probably not in the correct story order, sorry but that's the best I can do, I'm 201 years old and my mind is losing traction fast and my lap times are dropping to the point of no return.
Sorry I just wanted to add a little hummer, I didn't want my post to sound harsh, it's not intended too.
Rock

jtofast,
I think I did forget something, the rear roll center, you will need to raise it and I would start with around 11/1/2" to 12" adjust to tire temps and driver feed back.
Rock

Thanks for the input. We are going to try this and test this week. Thanks again.