Front Springs

[ask0329]

I have my own ideas of what happens but would like to hear some expert opinions. Car came with 800LB spring in the LF and 700LB spring in the RF. I switched them cause it seemed odd to me. It was my first time out and I know how the car felt (tight). Several onlookers said I pushed like a dump truck. What would switching them back do? Thinking I should stick to the previous owners baseline set up til I get used to the car. I dont want to go playing around in the rear end yet if I made a bad mistake by switching the front springs. If I'm correct, it would plant the Right Front better and help the car turn more? Probably going to switch them back regardless just to feel the difference.

[dirttrackrocker]

A few questions Andy. What type of clip? If it is metric what type lowers, stock or Nova? What type of shock travel? Is it bottoming out? My car is a Metric clip with metric lowers and I started with a 700 RF and a 750 LF Car pushed terrible. Switched them around and it was better at Dunn Hill (little 1/4 mile stop and go track) but at Black Rock (4/10 momentum track) it still pushed. Put an 850 in RF and it was better but still pushed in the center. Found that the right front was bottoming out. I trimmed the bottom of the frame and moved the top shock mount up and got another 1" of travel. Haven't tried it yet, but, I'm hoping it's better this week.

[ask0329]

Hey Kevin, Its a metric clip and I'm guessing stock lowers. Havent really checked the shock travel. It was my first real time out in the car and was more or less concentrating on the engine, tranny and not wrecking. Now that I feel confident in that I can work on the set up at the track and home a bit more. I did switch the springs back to the original set up (800 LF and 700 RF) and will see if there is any difference this week. I did put on zip ties to monitor the shock travel for this week. Part of it too may be that I'm just not used to turning an IMCA Mod yet. Brewerton is a tough track to begin with. Turn one is the Bottom of the D and a hard left, swooping out through 2. Turn 3 swoops all the way around into 4 and then just a quick turn out. 3 and 4 are fine. It was a nightmare in 1 and 2 and thats where I fell behind really bad as I couldnt get it turned. Just pushed out, let off the gas to get it turned then get going again. First year in an imca mod and its a helluva learning curve. The suspensions in these things are pretty wild.

[dirttrackrocker]

I'm in the same boat my friend.. LOL. I think your gonna find that the 700 in the RF is gonna make it worse. My bet is your having the same problem I had and the lower A arm is bottoming out on the frame. I had to go up to an 850 in the RF. You can also put a 1" offset wheel on LF or a wheel spacer to help getting in. More bite in LR will help in also, but, will tighten you up coming off. What type of car do you have?

[ask0329]

Its an older dirt works copy. So in short, home-made. I'll give it a try with the original setup and see how it goes. Only takes about 15 minutes to change the springs if its worse. How would I be able to tell if the A-arm is bottoming out?

[Dirtrunner35]

Some great reading By Mark Ortiz, I hope this helps.


Stiffening the right front spring, or adding preload to it, does load that tire more, and does mike it produce more corning force, in a left turn.

However, this comes at the expense of left front tire loading. The spring change can't change the total load on the front wheel pair, only the distribution of that total between the right front and left front. The spring change also can't change the total load on the rear wheel pair, the right wheel pair, or the left wheel pair, only the diagonally opposite wheel pair.

So rear wheel loads when cornering are also effected by the front springs. The total rear wheel load doesn't change, but it's right / left distribution changes, oppositely to the front wheels.

This means that with a stiffer RF spring, the front tires are loaded more unequally when cornering, and the rears are loaded more equally, than with a softer RF spring.

[Graff Spee]

Soften the rt front to make it turn again!

[dirttrackrocker]

Its an older dirt works copy. So in short, home-made. I'll give it a try with the original setup and see how it goes. Only takes about 15 minutes to change the springs if its worse. How would I be able to tell if the A-arm is bottoming out?

The metric lowers have a little hump in them, thats where the frame usually hits. You'll probably see a mark. My car was set up so the shock bottomed out at the same time the lower did, so I knew if the shock was bottomed out, the lower was also bottoming out.

[Dirtrunner35]

I have a chevelle clip and 650s in the front. Metric needs more spring. If your car was set up to work with the lighter spring in the RF and you switched the springs. The car will have more dynamic cross in the turns and could make it push with the stiffer spring on the RF. The transfer of weight will go to the stiffer spring first.

Try this at home. Take you scales and slide them together, put a different lb spring on each one. Put a board on top of all of them, place a 50- 100 lb weight in the center of the board. Which scale show the most weight??? The higher lb spring will, it doesn't absorb the weight like a lighter spring will. You added cross to the car in the turns. You could lower the cross and it may work for you.

Or it could be because your new to a mod.

[ask0329]

Thank you everyone for the input and education. I probably should of never changed it in the first place. I would hope and think that it already had a decent set up in it from the previous owner. (an expierenced mod driver). Regardless I have put it back to where it was and will find out tomorrow.

[wristpin]

Just remeber when you get the car down off the bars the car is not going to turn . My driver is new to and had a push but when he felt it push he lifted only made it worse. I would try losing the car up till you get it to turn. Then keep tighten it up every week. cause you will be driving it in harder each week as you get used to your ride.