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    #76
    Originally posted by 904dr View Post
    Not sure what you mean by start with a aftermarket set?

    350f 600r was just a guess right now. Im basing that number off other setups i've read other autocrossers used to win. But they were on ef civics something like 450f 600r. Im trying to get my inner rear wheel to lift, thats why I threw that stiff 600lb rear rate out there. I figure the front sway bar will take care of the softer front spring rate. I already have a progress rear sway btw.


    Thanks for the input. Any spring rate suggestions?
    What I mean by start with an aftermarket set is something like Neuspeed Race springs, for example. The better aftermarket companies have more racing experience than you and are going to provide you with spring with a rate that is in the ballpark already.

    Depending on your front sway bar so heavily isn't a good idea either. Sway bars increase lateral load transfer. If you have a large sway bar in the front, you're transferring more load to the outside front tire. This is taking grip away from your inside front, and since its a fwd, its making you slower. The sway bars should be used to fine tune things, but not as a main dependent.

    Also, just because civic guys use a certain combination of spring rates doesn't mean it will work for the accord. The motion ratios, sprung and unsprung masses, chassis, suspension geometry, etc are all different. The only way to really know is to measure. What you're after is a rear ride frequency slightly higher than then front. However, since fwd's are nose heavy, this is going to result in your spring rate still being higher in the front. People that run a higher rate in the rear are fooled into thinking the car handles better because of how the rear end rotates...but its really just hurting overall grip.

    You want a soft front bar and stiff rear bar so that you have as equal as possible of loading on both drive wheels, and the stiff rear bar will help put load on the front inner tire because of diagonal weight transfer.

    You really need to measure the car to know for sure what spring rates are good, and until then all you can do is guess. Being a fwd, you want as much forward weight distribution as possible within your class too. That will change up your spring rates as well. Remember, your rear will be proportionally stiffer than the front in terms of ride frequency, but as far as actual spring rate goes, the fronts will still be stiffer. Assuming your CB7 is fairly stock as far as weight placement goes, I would try something around 600lbs front, 400-450 rear...but again, you really need to measure the car to know for sure.
    There are no black and white suspension answers!!!!!!!!!!!

    Comment


      #77
      Back in the dd and autox days I used the ots gc rates of 400f 300r with both ST sway bars. It was a good compromise of comfort and performance. I started doing track days and then racing on this setup. I then ditched the st front bar and put the stocker back on. I then went with a cheap set of omni coilover, and their race rates of 560f 450r. Then I ditched the front bar completely. Then after some thought and imput from other racers I doubled my rear spring rate to 900. The car was able to accelerate better out of the turns as it limited weight transfer.

      So If I was in your shoes I would keep the 500f and try something 600-700rear, and it will ride much harsher on the street but it wont kill you and it is only one set of new springs, try it out and see how the car handles. Make one change at a time so you can tell what that change is doing.
      1990 accord Honda-Challenge, H22 powered
      newer race video,older race videos
      1991 accord parked, parts and back up shell
      1993 accord acquired 6-11-16

      Comment


        #78
        Originally posted by mndude07 View Post
        What I mean by start with an aftermarket set is something like Neuspeed Race springs, for example. The better aftermarket companies have more racing experience than you and are going to provide you with spring with a rate that is in the ballpark already.

        blah, they are good for getting groceries, not for the track in most cases

        Depending on your front sway bar so heavily isn't a good idea either. Sway bars increase lateral load transfer. If you have a large sway bar in the front, you're transferring more load to the outside front tire. This is taking grip away from your inside front, and since its a fwd, its making you slower. The sway bars should be used to fine tune things, but not as a main dependent.

        very true, you do not want to transfer load from the inside front where there isnt much to begin with

        Also, just because civic guys use a certain combination of spring rates doesn't mean it will work for the accord. The motion ratios, sprung and unsprung masses, chassis, suspension geometry, etc are all different. The only way to really know is to measure. What you're after is a rear ride frequency slightly higher than then front. However, since fwd's are nose heavy, this is going to result in your spring rate still being higher in the front. People that run a higher rate in the rear are fooled into thinking the car handles better because of how the rear end rotates...but its really just hurting overall grip.

        so why don't you calculate some ride frequency for us and tell us what the magic number is? FWD is a compromise, you NEED to reduce rear grip to maintain neutral handling.

        You want a soft front bar and stiff rear bar so that you have as equal as possible of loading on both drive wheels, and the stiff rear bar will help put load on the front inner tire because of diagonal weight transfer.

        or no front bar

        You really need to measure the car to know for sure what spring rates are good, and until then all you can do is guess. Being a fwd, you want as much forward weight distribution as possible within your class too. That will change up your spring rates as well. Remember, your rear will be proportionally stiffer than the front in terms of ride frequency, but as far as actual spring rate goes, the fronts will still be stiffer. Assuming your CB7 is fairly stock as far as weight placement goes, I would try something around 600lbs front, 400-450 rear...but again, you really need to measure the car to know for sure.
        100% front axle weight couldn't hold a steady state turn without spinning, 50-50 on a fwd would hurt for forward bite, like most things it is a compromise
        1990 accord Honda-Challenge, H22 powered
        newer race video,older race videos
        1991 accord parked, parts and back up shell
        1993 accord acquired 6-11-16

        Comment


          #79
          I appreciate the educated advice Karl.

          When I saw your sig I had to pm you, I assumed you must have some insight.

          When I order new sleeves from gc for my koni's, i'll see if they have something around 700.

          Comment


            #80
            Originally posted by Karl View Post
            It depends on your track conditions what kind of spring rates are going to work best. Too stiff on a rough track and you'll be skating over bumps. Too soft and you don't have enough roll resistance.

            Put me near a shop with corner scales and I will calculate it. There is no "magic number" though. What is that supposed to mean? It is going to be different for every car, especially if you have things like a motor swap, gutted trunk, lighweight wheels, etc. You're trying to compare apples to oranges by comparing spring rates on a civic to spring rates on an accord. You don't seem to have much of an understanding about ride frequency.

            No front bar at all is again, a wild assumption. You have no idea what its doing compared to different sized sway bars. A smaller than stock diameter sway bar could be the best for your chassis, you have no idea because you haven't measured.

            100% front axle weight is impossible. That was a ridiculous comment. You would have a 2-wheeled vehicle then. Let me re-word my statement: You want as much front biased weight distribution as possible in a FWD without throwing your center of gravity out in front of the contact patch.

            Yes of course you are trading rear grip for front grip. I explained all that by saying a large rear bar is going to load up your inside front tire through diagonal weight distribution. Your overall grip is still going to be higher.

            There are no black and white suspension answers!!!!!!!!!!!

            Comment


              #81
              Originally posted by mndude07 View Post
              It depends on your track conditions what kind of spring rates are going to work best. Too stiff on a rough track and you'll be skating over bumps. Too soft and you don't have enough roll resistance.

              right, but I don't have different spring and shock packages for different tracks, I am a club racer. I dont know of anyone that makes track dependent changes at the club level either, most get the car dialed in and go. Yes it is a compromise.

              Put me near a shop with corner scales and I will calculate it. There is no "magic number" though. What is that supposed to mean? It is going to be different for every car, especially if you have things like a motor swap, gutted trunk, lighweight wheels, etc. You're trying to compare apples to oranges by comparing spring rates on a civic to spring rates on an accord. You don't seem to have much of an understanding about ride frequency.

              How are you measuring the wheel rate? Motion ratio and spring rate only? What about sway bars? What about bushing sticktion?

              I never compared civic vs accord spring rates. I do use the information provided by many sources who have many different make and model cars with all kinds of engine and drive-train layout suspension design and weight distribution. I combine that information with how the car "feels" to come up with the hypothesis for the changes. Feel is something no math formula will tell you.


              No front bar at all is again, a wild assumption. You have no idea what its doing compared to different sized sway bars. A smaller than stock diameter sway bar could be the best for your chassis, you have no idea because you haven't measured.

              Right, because I have used a stock front sway bar, an after market front sway bar, and no front sway bar I am making a wild assumption about what it does.

              100% front axle weight is impossible. That was a ridiculous comment. You would have a 2-wheeled vehicle then. Let me re-word my statement: You want as much front biased weight distribution as possible in a FWD without throwing your center of gravity out in front of the contact patch.

              Still disagree unless you are talking about drag racing

              Yes of course you are trading rear grip for front grip. I explained all that by saying a large rear bar is going to load up your inside front tire through diagonal weight distribution. Your overall grip is still going to be higher.

              rear roll resistance helps front grip, it does not have to come from a sway bar
              cool
              1990 accord Honda-Challenge, H22 powered
              newer race video,older race videos
              1991 accord parked, parts and back up shell
              1993 accord acquired 6-11-16

              Comment


                #82
                Originally posted by Karl View Post
                cool
                right, but I don't have different spring and shock packages for different tracks, I am a club racer. I dont know of anyone that makes track dependent changes at the club level either, most get the car dialed in and go. Yes it is a compromise.

                Fair enough

                How are you measuring the wheel rate? Motion ratio and spring rate only? What about sway bars? What about bushing sticktion?

                Motion ratio and spring rate are all you really need. You can take the sway bar into the equation, but it isn't doing anything in ride, and also if your sway bar is so stiff that it is having an effect on your damping (and thus wheel rate) then you need a softer bar and stiffer springs anyway. As far as bushing sticktion and deflection goes, you would assume there are sphericals installed. There is no way to take such small deflections into account, only computer simulations and estimations...assuming solid joints is the most accurate way.

                I never compared civic vs accord spring rates. I do use the information provided by many sources who have many different make and model cars with all kinds of engine and drive-train layout suspension design and weight distribution. I combine that information with how the car "feels" to come up with the hypothesis for the changes. Feel is something no math formula will tell you.

                Alot of what "feels" good and what is actually happening isn't the same thing all the time. Data loggers are good for that...

                Right, because I have used a stock front sway bar, an after market front sway bar, and no front sway bar I am making a wild assumption about what it does.

                You said no front bar as if its "the best" or something. I'm only suggesting that something in between might be more ideal. Since there isn't an aftermarket bar smaller than stock that will bolt on, I can assume you haven't tried it.

                Still disagree unless you are talking about drag racing

                Why do you disagree? I would like reasons and hard facts. Lets talk about physics. Why would you want more weight to transfer off your drive wheels?

                rear roll resistance helps front grip, it does not have to come from a sway bar

                True, but the sway bar increases weight transfer across the two rear wheels, and without it..or too small of one, you won't be able to limit your roll angle to where it needs to be. And since you aren't transferring as much weight laterally in the rear, you aren't loading up that inside front.
                There are no black and white suspension answers!!!!!!!!!!!

                Comment


                  #83
                  Originally posted by wed3k View Post
                  and why would you do that? you dont achieve anything. you really dont want any delay between the two. either off or on...

                  the spilit second for my foot to go from gas to brake, i feel, is too slow of a reaction and the during an auto-x you only have spilit seconds.
                  if you watch and study any of the HOT MOTORING episodes. (pro jap racers testing and racing peoples cars that they have built) i see them left foot brake all the time in ff cars. even after they have rev matched (toe heel) i'm sure they do it for better lap times

                  Comment


                    #84
                    You can run GC's at over 500in/lbs with out revalving you koni's...well I think or would it be to spring for the koni's to handle?

                    Comment

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