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  • Really? I felt my 8610's had quite a bit of compression. Roughly equal to setting 2-3 in compression on the 8611's. They definitely have some gas pressure, just like all 8610 Sports.
    '18 Chevrolet Volt - Electric fun hatch for DD duty!


    DefSport Koni Sleeve and Spring Perch Buy!!!
    http://www.nissanroadracing.com/showthread.php?t=5902

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    • I'd say it's all of the above. When I was trying to keep the inside rear from spinning with my HLSD, I softened up the rear shocks quite a bit on my car. I wound up picking up the inside front on corner exit, even with only 150whp and hard 225 width tires.

      http://blehmco.com/pics/track_pics/h...2/L-%20173.JPG (linked because it's a 3MB photo)

      You can see the rear sway is disconnected in that photo as well. I've since stiffened up the rear shocks and still run no sway bar. I spin the inside tire on corner exit, but that's better than the poor handling from having the shocks too soft.
      Originally posted by SoSideways
      I don't care what color they are as long as they are LONG AND HARD.
      '04 G35 Sedan 6MT- The DD
      '96 240SX- The Track Toy

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      • Originally posted by Matt93SE View Post
        I'd say it's all of the above. When I was trying to keep the inside rear from spinning with my HLSD, I softened up the rear shocks quite a bit on my car. I wound up picking up the inside front on corner exit, even with only 150whp and hard 225 width tires.

        http://blehmco.com/pics/track_pics/h...2/L-%20173.JPG (linked because it's a 3MB photo)

        You can see the rear sway is disconnected in that photo as well. I've since stiffened up the rear shocks and still run no sway bar. I spin the inside tire on corner exit, but that's better than the poor handling from having the shocks too soft.
        All why should buy my extra Cusco RS.
        '18 Chevrolet Volt - Electric fun hatch for DD duty!


        DefSport Koni Sleeve and Spring Perch Buy!!!
        http://www.nissanroadracing.com/showthread.php?t=5902

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        • Jason - I can't remember, did you verify the pressure ring was assembled in the correct orientation from the factory? Shouldn't spin the inside tire. They were giving me the same line about the shock settings and suspension set up BS for two yrs. The pressure ring was assembled upside down at the factory. OS Giken US even inspected it and assembled it incorrectly again. Since I assembled it correctly, I can't get just the inside tire to spin. Both hook up and grip. Completely different (BETTER) car to drive. Since mine was assembled incorrectly it makes me think there is probably a lot of this part number affected.
          Last edited by 240sxTTC; 06-19-2014, 11:30 AM.
          NASA Time Trials TT3


          BTW I work for Garrett

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          • ^^^tt, after reading about your issues with the Giken, the first thing I checked was the orientation of the pressure rings, compared to the center cross bar cams. Unless I had everything backwards in my head (as far as power distribution goes), it was assembled correctly. (btw... I finished welding your RLCA's last night!)

            The whole reason I went with the Giken as a diff option, was becuase of the tunibility. I'm very discouraged that they won't sell me tuning parts. There is a recognized issue by OS giken about inside wheel spin of an unloaded tire do to lack of pre-load and the basic design of the unit, on high power/torque applications, however, you'd think that the cam would lock up the clutch packs rather quickly, but the inside wheel spin occurs for a significant period of time on my Sm prepped chassis.

            I'm considering removing some of the anti pre-load springs, which are suposed to be primarily lock timing adjustments. GEEKEN recommends stiffer cone springs for increased pre-load, but they do admit that they have used a couple different cone springs in their units and it could vary from diff to diff (They say that they'd have to inspect my unit to see what cone springs I have installed). After going round and round with GEEKEN trying to figure out how to resolve my issue, they told me that if I have anymore questions to just email sales, and basically hung up the phone on me.

            My thoughts are that I need quicker lock up, and that removing the anti preload springs should increase net preload on the clutch packs at the same time.

            Edit: I wanted to add that I think autoX cars might notice the issue more then road racers. I only notice the issue upon accelerating through/out of very tight radius corners.
            Last edited by Jason M; 02-18-2015, 08:36 PM.

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            • Originally posted by Def View Post
              Really? I felt my 8610's had quite a bit of compression. Roughly equal to setting 2-3 in compression on the 8611's. They definitely have some gas pressure, just like all 8610 Sports.
              Well my 8610's must be blown & or worn out then. The've been like that for the last couple years...

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              • Originally posted by Jason M View Post
                ^^^tt, after reading about your issues with the Giken, the first thing I checked was the orientation of the pressure rings, compared to the center cross bar cams. Unless I had everything backwards in my head (as far as power distribution goes), it was assembled correctly. (btw... I finished welding your RLCA's last night!)

                The whole reason I went with the Giken as a diff option, was becuase of the tunibility. I'm very discouraged that they won't sell me tuning parts. There is a recognized issue by OS giken about inside wheel spin of an unloaded tire do to lack of pre-load and the basic design of the unit, on high power/torque applications, however, you'd think that the cam would lock up the clutch packs rather quickly, but the inside wheel spin occurs for a significant period of time on my Sm prepped chassis.

                I'm considering removing some of the anti pre-load springs, which are suposed to be primarily lock timing adjustments. GEEKEN recommends stiffer cone springs for increased pre-load, but they do admit that they have used a couple different cone springs in their units and it could very from diff to diff (They say that they'd have to inspect my unit to see what cone springs I have installed). After going round and round with GEEKEN trying to figure out how to resolve my issue, they told me that if I have anymore questions to just email sales, and basically hung up the phone on me.

                My thoughts are that I ned quicker lock up, and that removing the anti preload springs should increase net preload on the clutch packs at the same time.

                Edit: I wanted to add that I think autoX cars might notice the issue more then road racers. I only notice the issue upon accelerating through/out of very tight radius corners.
                I switched to the 1.8 preload cone springs after the first event with the new LSD because of inside wheel spin. It didn't change the inside wheel spin at all. Before I correctly assembled the pressure ring, I did take out a set of the negative preload springs. The negative preload springs don't affect the amount of force applied to the clutch packs just how fast the pressure ring opens up. The force applied to the clutch packs is related to the cam ramp angle. This is why when the pressure ring was backwards and the smaller angle was on the accel side, it didn't load the clutch packs enough and allowed inside wheel spin. I sent you an email with photos of the cam/ramp angles when the pressure ring was backwards in my LSD so you can compare to yours.

                Cool....can't wait to see the finished RLCA's! Thanks.
                NASA Time Trials TT3


                BTW I work for Garrett

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                • I really don't understand why they won't sell tuning parts to the general public. Mr. Hard Parker is not going to bother tweaking things inside the diff he gets because MotoIQ said it was "the best." I mean, make some profit off of it and sell a full package of springs and whatnot for $75-100 or something that maybe costs them $20-30.

                  You can get all the parts you'd like to tweak a Cusco RS.

                  I'm not sure if it'd work for us (maybe), but they have a "Pro" version of their RS for GTRs where you can swap out to modular ramp angles. Sounds really snazzy, and probably a more powerful tuning tool than tweaking preload and anti-lock springs which only affect a small part of the overall lock vs. power curve, and some only in the time domain.
                  '18 Chevrolet Volt - Electric fun hatch for DD duty!


                  DefSport Koni Sleeve and Spring Perch Buy!!!
                  http://www.nissanroadracing.com/showthread.php?t=5902

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                  • ^^ Agree. However, I'd think they would have to at least sell the preload cone springs as they are definitely a wear item.
                    NASA Time Trials TT3


                    BTW I work for Garrett

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                    • Originally posted by Jason M View Post
                      I do only have 1.5" droop up front. I think the main culprit is the big bar up front, prying up the inside tire.
                      I was thinking similar....except opposite...(Maybe my thinking is backwards so correct me if I'm wrong); my understanding is that sway bars work against the unloaded tire...IE: the LF compressed means the bar is trying to lever the RF into the ground.

                      I think you might have a combination of too much rear weight transfer for your amount of front droop (springs or dampening) and also some sway bar issues hurting the cars' performance.

                      ...However, if you don't have alot understeer on corner exit and the car is great everywhere else then maybe the front lift is acceptable. ..IDK how that would affect the car in quick transitions though...Probably not a great endurance setup, but ehhh...Autox moves pretty quick!

                      Cheers
                      Ch



                      Sent from my SM-N900V using Tapatalk

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                      • Your backwards there. When the lf corner compresses the sway bar tries to compress the rf corner. best way to picture it is the bar wants to remain flat when the left side is compressed it will try to compress the right also. This is also dependent on spring rates too, for example if your springs are stiffer than the bar it will apply pressure the loaded tire pressing it into the ground. If your springs can are softer than the bar it will try to lift the unloaded tire off the ground
                        Originally posted by a250gpguy View Post
                        I was thinking similar....except opposite...(Maybe my thinking is backwards so correct me if I'm wrong); my understanding is that sway bars work against the unloaded tire...IE: the LF compressed means the bar is trying to lever the RF into the ground.

                        I think you might have a combination of too much rear weight transfer for your amount of front droop (springs or dampening) and also some sway bar issues hurting the cars' performance.

                        ...However, if you don't have alot understeer on corner exit and the car is great everywhere else then maybe the front lift is acceptable. ..IDK how that would affect the car in quick transitions though...Probably not a great endurance setup, but ehhh...Autox moves pretty quick!

                        Cheers
                        Ch



                        Sent from my SM-N900V using Tapatalk

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                        • With zero spring preload, I struggle to come up with a difference between a spring/sway tire load and a pure spring load with the same roll stiffness.

                          The tire lifting thing is just a consequence of zero preload and a really high roll stiffness while compressing the outer corner beyond what the inner corner can extend.
                          '18 Chevrolet Volt - Electric fun hatch for DD duty!


                          DefSport Koni Sleeve and Spring Perch Buy!!!
                          http://www.nissanroadracing.com/showthread.php?t=5902

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                          • So, I'd like everyone's opinion on my front & rear sway bar setup. (don't worry, I won't be offended)

                            I'm not sure exactly how much bar to run (thats why I'm testing all these different setups), but the rule of thumb (info gathered from online research)for a front engine rear wheel drive chassis, is 25-50% of your front wheel rate should be bar, and 10-25% of your rear wheel rate should be bar.

                            Here is my Data...
                            Edit: My motion ratio during the testing below is .910:1, to .980:1, and is actually rising rate, in a digressive fashion. My original MR testing was inaccurate due t a malfunctioning china built dial indicator...






                            All Bar tests were performed from full droop allowed by the bar, the first .5"-1" (depending on bar stiffnes), is mostly unsprung wieght readings, and not the bar rate. For acutal bar stiffness look from .5"to 1" and up on the graphs. You'll see it right away by how linear the data gets...
                            Bumpsteer graph (multiple steering angles)
                            Last edited by Jason M; 06-25-2014, 09:39 PM.

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                            • Re-measured my front suspension after noticing some discrepancies between my real world measured data, and my suspension analyzer software calculations.

                              I had some how incorrectly measured my front suspension motion ratio. The MR is actually a rising rate, in a digressive fashion... (I'm going to blame a cheap china made dial indiactor!)





                              Camber curve, as measured...

                              Last edited by Jason M; 06-25-2014, 10:26 PM.

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                              • After blowing three 86 series koni race inserts over the last three seasons, I've finally had enough of the "Koni experience".

                                I've called Koni directly multiple times, and left messages. They failed to respond one time. I emailed them, and they finally got back to me almost one week later stating that it's probably not worth it to rebuild my shocks, and that it would not be possible to have them serived within two weeks...

                                Called Proparts, and they did not think they could get them done within three weeks, and when I asked them about re-valving, they told me "we just know how to valve them from experience...) Thats just not good enough for me, I'd like to know how and why they determine specific valving profiles.

                                I'm a diy kinda guy, so I've decided to go the Bilstain route. They are high quality, easily serviceable, and tuning parts are bountiful. Also, many different companies offer revalving services, if required.







                                Both inserts weight about the same, so that's a wash, but on paper the Bilstein monotube is superior to the twin tube 86 series Koni.


                                Bilstein insert...


                                Machined down the supplied wiper seal, and pressed it into the GC coil over sleeve.













                                Machined a conical spacer for maximum articulation for the camber plate spherical.




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