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This is a general question that started in the shop. How soft can you go on front spring rates? Lets say the track is a big 1/2 mile with very little banking and sweeping corners. I know lates are getting really soft in the front. Just looking for ideas on pinning the right front.
Depends on what clip what control arms. I have run as soft as a 500 on the RF and 425 on lf. Metric clip with tube nova lowers.
Bumpstops or no bumpstops??
Chevelle front stub stock lowers and no bump stop. Four bar car. Is there a difference between bump stop and no stop like just bottoming out the RF shock?
Bump stops run really soft springs so you are actually running on the bump stop and not the spring when the car rolls over.
Im trying a 450 RF, and 500 LF in my IMCA type modified this weekend. No bump stops. 1/4 Mile Semi-banked. Usually gets dry for features. Stock lower control arms, adjustable uppers. QA1 Balljoints.
4 bar/4 bar suspension with ford 9"
What should I expect?
Expect it to be very soft lol. You will have to drive the car with finesse. You can't go throwing it into the corners like a tank. Gotta be really calm an smooth.
So is it possible to get into the 500- 450 range on the front of a modified? I know there is no magical set up and you just can't beat hard work and homework in the shop. Just trying to find out if it is possible for this to work.... get faster....win....
Run what your driving style suits. In order to be soft on the front end, you need to not be depending on a lot of forward traction, but more momentum. It is pretty tough in an IMCA Car (No blade in the back and no lift arm) to run less than a 500 in the RF.
I decided not to soften mine right now. Last week the track had deep ruts in the center of the turns. I think going softer will only hinder the cars performance. Im still fighting forward bite problems, but thats a whole other thread.
I would often swap springs at the track depending one the shape of the track. If it was rough I would run a heavier spring and shock package. If it was slick and smooth I would run aonther combo. Some times I would even swap between the heat and the main.
I would go as soft as possible, that way way everyone can brag to their fellow racers how soft their springs are.
Have any of you people ever figured the motion ratios, and what the soft springs rates actually compute to rate at the spindle? Then you put a shock on the RF with virtually no compression dampning, and a ton of rebound and hold the weight on the RF, when you do that, what spring are you unloading.....the LR.
If the soft front end doesn't work, you might get ahold of Jason Hughes, Ryan Gustin, Jared Landers and let them know that they can go a lot faster.
I would bet all those guys are running on bumpstops....
I would bet not.
That stuff may work in the IMCA, and the sanction bodies that run the hockey puck tires.
hughes had a 600 in his RF at las cruces a few months back. I know he doesn't run it everywhere, but like most of the guys that run up front consistently, he knows that there is no one magic bullet for all track conditions. People got really hung up on running the softest stuff possible a couple of years back, but there are a lot of open shows being won on 550's and 600's in the RF right now. I'd say the majority of them most likely. We've won 4 shows (1 "big" and 3 weekly) in our new hughes car, at 2 different tracks. We're running a 500 on the little (very round corners), flat track, and a 600 on the bigger, higher speed track. Different things work for different people, and 400-450 stuff has it's place. But, I would never assume that a 400 is better than a 550 just because it is softer. You have to give the car what it needs for the condition at hand.
On a 4 bar car the LR is loaded by the traction device and the bars 90+% of the time the spring is not even loaded. You can find chassis videos on Youtube where you can see that the spring in only in play when the car is off the gas going into the corner. The RF compressed gets the car in position for the bars to come into play the instant that the throttle is picked up. To make this work you must be smooth and trail brake into the corner and not toss and stomp.Quote:
Originally Posted by JustAddDirt
Yeah, Just Add Dirt, what do you know anyway. You dont ever win any races do you!LOL
If your rf spring is so soft that when you lift you see the rf tire jump up over the hood and the car turns sideways, you wont have any traction regardless of whether the lr spring is loaded or the 4 link bars are standing straight up.
I think I can speak for JAD by saying You all should run as soft of a spring as you can get that way it will be easier for him to keep winning.
You have to give YOUR car what YOUR car needs. Every brand of chassis is different, every race track is different and every driver enters the corner different.
Like I said, do what your car needs, but I know the soft stuff works if you know how to tune for it.
I agree, but in IMCA, you can't get away with anything under a 500. It has more to do with a suspension setup in the back than it does just being a soft spring. Tires with more traction, obviously won't need as soft.Quote:
Originally Posted by JustAddDirt
Hmmmmmm......I wonder why supers are running a 200-225 RF spring rate (stacked of course)
Why arent some of you mod guys doing it?
It can be done, as I have put one on a car already.
Quote:
Originally Posted by drtrkr244
stacked coil overs are a whole different ballgame obviously...
Each car will be a little different, so youll have to: 1)remove spring
2)back wedge bolt all the way to the top
3)measure from bottom of wedge bolt plate to bottom of lower spring mount
4)Search the spring mfrs to find 2 spring heights that will fit.
That should be enough info to get yall thinkin what you will need to finish it!
I beleive you will find that you need a little heavier rear springs with your soft front springs. Before you change back to what you currently have try a stiffer compression right front shock if bottems out to quick. Also might have to raise ride height a little.
Is a c/o on the front legal in the mods?
Another tidbit of info; Just think of using the wedge bolt like a c/o.
You stack them because if you tried to run a single spring of that weight it will bow and twist and it will not last. We have run a 650 LF, 275 RF 133LR and a 225RR in a winning crate latemodel.Quote:
Originally Posted by stock car driver
I have not found any negatives to running a stacked spring setup. Once you get it setup properly , you just set it and forget it.They are not as temperamental as some people say they are.
There has not been many setup inventions that gives as many positives without the negatives.
You get the combined soft rate to get in the corner, and the stiffer bottom spring to get you off.
what mod classes allow more than 1 spring per wheel?
Exactly what I was thinkingQuote:
Originally Posted by stockcar5
On the car , Where I put the stacked spring, you wouldnt know theres two springs there.Their both the same color and with the spring tucked under the frame you hardly notice it.
My guess is he is using pull bar springs. At least the top one would have to be because its flat on both ends.
around here guys that get in the top 4 get teched. that wouldnt last to long. how does your car handle when it legal?Quote:
Originally Posted by drtrkr244
It belongs to a customer of mine. This weekend will be the first race with the stacked spring.
I matched the motion ratios with a lm, so I dont expect any problems.
OK gentlemen with race night done and over I can say the soft right front does work and no bump stop on the RF. The car drove great in--thru and off the corner with that said the only problem being able to break the tires loose going down the straight at will.
adjust the driver's right foot rate of throttle application :-)Quote:
Originally Posted by fastonraceday
I'm not sure his driver came with that option!