tooquick260 Posted February 27, 2013 Share Posted February 27, 2013 Here is my best run. Got 16 runs for the day. First time out with the Cosmoracing spring set. 6k front and 8k rear. Decided after the event need to switch front to back. Also still running the stock original shock inserts. The bounce and rebound is aweful, thought that the soft stock suspension was ok but man you put the suspension under a hard load and they are shot. This is shot with my Iphone using the otrix case holder that has a built in wide angle lens. I used the vidometer program to get the MPH, G's, altitude and horizon level/tilt. Quote Link to comment Share on other sites More sharing options...
johnc Posted February 27, 2013 Share Posted February 27, 2013 Don't even bother swapping the springs until you get some shocks that can handle those rates. No Tokicos, no KYBs. You can probably get by with some Bilstien P30-0032s but Koni 8610s are a better choice for the spring rates you've chosen. Or, you can toss those Cosmo springs and put in spring rates down around 200 to 250 lb. in. and run the Tokicos. Quote Link to comment Share on other sites More sharing options...
tooquick260 Posted February 28, 2013 Author Share Posted February 28, 2013 So what is the issue with running the Tokicos or KYBs'? I have heard that before. The setup with these springs seem really soft. Had the instructor ride with me on one run and he is suggesting to put the 8k in front and the 6k in the rear. When I had the 5k on the front and the 6k on the rear the suspension would bottom out under little to no load. So I got the 8k and put on the rear with the 6k on the front and it only bottoms out on extreme bumps. I am new to all this so any info would help. I know the Cosmoracing is not suppose to be an all out road racing setup. I have never been around anyone setting up a car for road racing. Watched my dad for years tuning drag racing suspensions, with really soft front springs to transfer weight and progressive setup in the rear to let suspension set and hold the transfer. he ran Koni's for years then went to QA-1's with 2 way adjusting. Help novice, poor wanna be autocross driver! Quote Link to comment Share on other sites More sharing options...
BluDestiny Posted February 28, 2013 Share Posted February 28, 2013 You are overspringing the shock, and it sounds like you have blown shocks anyway. Imagine having to pull a a thin metal disk through oil, with the flat part going against the direction you are pulling. Now imagine going 50x faster. You're going to put more stress on it and possibly bent the disk. That's what you are doing to your shocks. They are not valved to handle those springs. Quote Link to comment Share on other sites More sharing options...
tooquick260 Posted February 28, 2013 Author Share Posted February 28, 2013 Ok,, I think I understand. The spring rate makes the bounce back sharper or faster and the dampening of the shocks will get blown out!! Saving for shock inserts, along with tranny, drive axle, rear diff, seats, strut tower braces and tires. Can you say lottery, poor part time worker part time student with no money! Quote Link to comment Share on other sites More sharing options...
JMortensen Posted February 28, 2013 Share Posted February 28, 2013 I know it's autox and you're not likely to need it, but strap your helmet on. Quote Link to comment Share on other sites More sharing options...
johnc Posted February 28, 2013 Share Posted February 28, 2013 Maybe my math is wrong, but a 8Kg/mm spring has a rate of 447 lb/in. I'm an old USA racer and I have to convert things into a measurement system that is approved by God. Shocks control the rate of extension of a compressed spring and the rate of compression of an extended spring. They do not add to the spring rate itself, just control the storage and release of potential energy in the spring. Shock valving works via hydraulics and rely on the incompressability of fluids to change some of the potential energy in the spring into heat. Shock oil is pushed through valves and ports in the shock at different rates depending on how fast the shock shaft is being moved and for our cases we don't care about anything faster then about 14" per second. Within the mechanical limits of the shock design, there are limits to how much force from the spring the shock valving and oil can control. If you exceed those limits the oil cavitates (air pockets form), the valving gets distorted beyond the material's yield limit, and/or things get hot enough inside that seals start to leak and the oil viscosity drops. Tokicos will tend to lose the upper gas seal and the adjuster valve fails open in the piston when the spring rate exceeds the shocks design limits. KYBs just go woogy. Quote Link to comment Share on other sites More sharing options...
tooquick260 Posted March 2, 2013 Author Share Posted March 2, 2013 Wow that is a lot of experience, knowledge and readinig in that statement. Thanks I was thinking that was somehow the way suspension works. Quote Link to comment Share on other sites More sharing options...
RebekahsZ Posted March 2, 2013 Share Posted March 2, 2013 (edited) Welcome to the fun and thanks for sharing your video! Please take it well, but here are a few driving pointers: Get into 2nd gear quicker and leave it there-you should be able to go as slow as 10mph and up to 60mph in 2nd gear. Quit putting your hand inside the steering wheel-keep it on the outside with your palm down, and don't hand-over-hand on tight corners-your hands should never cross. Once you are in 2nd gear and dont need to clutch, use your left foot on the brake and your right foot on the gas. There was a lot of coasting in that video-that is wasted time. The next part I would buy, if I were you, is a seat with side support and a harness to keep your body in place-you are flopping all around-the stock z-car seats have the same support as a park bench. A quick alternative to a new seat is a 1X1" board bolted to the floor for your heals to brace on so you can stay in your seat. When you are in a straight section of track-floor it! I only heard your tires spin once. You've got a lot more speed in your current system, but you seem like you are out getting groceries with a helmet on. If you didn't spin out and knock a ton of cones down on at least one run-you aren't trying hard enough. But not on every run...did you have any trouble with brake fade (spongy pedal, ineffective brakes)? If not, you aren't pushing hard enough. You should boil your brakes at least once. Your tires and brake should be hot as hello at the end of the run. What a great club that allows you to get 16 runs! The most I've ever gotten on an autocross day is 8 runs-I'm jealous! Edited March 2, 2013 by RebekahsZ Quote Link to comment Share on other sites More sharing options...
tooquick260 Posted March 3, 2013 Author Share Posted March 3, 2013 Thanks for putting in your knowledge/experience and opinions in the thread rebekah. I will definitely work on the things you told me. The one thing about flooring it on a straight, I am, the car is slow hehe. My brother's 1.6 liter Kia Rio is faster in a drag race. Ya my seats are horrible, on my way home i noticed i had a softball sized bruise on my hip from banging the door. I agree on the braking, i am very timid on my brakes and have always had a fear of locking them up since my previous car's brakes were utterly horrid. It was my first time autocrossing so any hints are very much appreciated. To live is to learn and to learn is to live! The tires are flat worn out. BFGoodrich G sports that were roasted from my 240sx. Oh and even though i may look slow, my times were faster then a turbo rx8 and only half a second from 2 of those new Subaru Brz's =D Quote Link to comment Share on other sites More sharing options...
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