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This topic was originally posted in this forum: Modified Tech Talk
Author Topic:   shock ideas
old racer
Member
posted July 18, 2003 04:18 PM     Click Here to See the Profile for old racer     
Has anyone tried to tie the right sides down with tiedowns and used easy ups on the left?The latemodels are really sticking the car on black slick with this deal. I keep wanting to do it on the modified but don't have the proper shocks and don't want to throw money out the window if it is not the ticket. Our car is decent on dryslick right now. Any thoughts?


Chad
Member
posted July 21, 2003 09:50 AM     Click Here to See the Profile for Chad   Click Here to Email Chad     
I can't believe no one has responded to your question. I am running the exact shock package you explained on my new DW8 4 bar modified. I'm using Bilstein shocks and the shocks are:
LF 3050 RF 6030
LR 3050 RR 5030
Remember, the first number on a Bilstein is Rebound/Compression. Car really gets over good and sticks real well. Haven't had any dry slick tracks to try, but I know it should work well. You may want to also consider running linear valving on the front shocks. It should give you a better feel of the car on a dry track. Most of the top cars are using linear shocks on the front with the digressives on the rear.


lucky13
Member
posted July 21, 2003 05:18 PM     Click Here to See the Profile for lucky13     
We've only tried the tie down on the RR and talk about 3 foot wheelies! We have never tried one on the RF.

Old Racer: There definately is something to the chassis tuning by shock heat. I know I had mentioned something about it before, but I wasn't sure if it was importatnt or not. It seems like it is on a long green run. We got our shock temps (within 5 degrees)evened out and now the car doesn't change much from beginning to end of the feature. It also seems like to car is smoother everywhere. I don't know if this is because we have gotten the suspension movements evened out a bit from right to left? As a coincidence, our tire temps have stayed very equal with about 1/2 to 1 1/2 inches stagger. I don't think a guy should start basing his whole setup off of the shock temps, but it seems like it is a useful tool.

old racer
Member
posted July 21, 2003 07:39 PM     Click Here to See the Profile for old racer     
Lucky 13, I talked with a very knowledgable friend today and we started talking about shock temps, he says that the shocks lose efficiency like crazy when the shocks reach anything over 120 F. He says alot of us are blaming tires for what is actually happening to the shocks during the race. He has a shock dyno and we're going to do some more testing in regards to shock temps.
I am going to throw a week away on the tie down deal just to reach my own conclusion. I'll let you know.
Chad, How much rear wt % are you running. I've been told that it is not necessary to have extremely high rear wt. with this deal because you are sticking the rights and keeping momentum up. Do you notice the RR tire getting hotter or not? I was surprised that no one wanted to talk about this either.
Thanks for the input guys.


modman97
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posted July 21, 2003 10:16 PM     Click Here to See the Profile for modman97   Click Here to Email modman97     
Interesting concept.
I too have seen some logical ideas in the past here that no one had commented on. Is it because its a deep dark secret, or because guys are scratching thier heads with both hands and cant type?
OLD RACER- Check your PM's


fastow
Member
posted July 21, 2003 11:23 PM     Click Here to See the Profile for fastow     
Lucky : I just started paying attention to this shock temp I had a stock car guy tell me he had some kind of shocks that he was over heating and going away. My thought on that was how can you over heat a shock when you run a 20 lap feature with maybe 8 or 10 laps of racing without a caution. On the mod I have check them like after a heat and some features and have never found them to be maybe 5 to 10 degrees different from the frame right next to them. the fronts is just about the outdoor temp and the backs are a little warmer I think cause of all the heat from engine trans and rear end. My opinion right now is I think heat build up in a shock may happen in a long race with no yellows. and that don't happen around here. Maybe just alot of hype ?????? Or maybe we could run coolers on our shocks LOL


lucky13
Member
posted July 22, 2003 05:41 AM     Click Here to See the Profile for lucky13     
I think it is probably only likely to make any difference on a long green or maybe a really rough track. If old racer's buddy is right and all it takes is 120+ degrees, than I doubt any of us can feel the difference from that to the outside air after a race (without a temp gun).

Old racer- I am in the neighboorhood then, as our temps were running up there around 115-120 (as hot as 135) and now we are down around 100-105 unless it is really rough. Funny thing is we still have a lot of car movement, but the heat went away.

Thanks guys.

Chad
Member
posted July 22, 2003 11:28 AM     Click Here to See the Profile for Chad   Click Here to Email Chad     
Old Racer- I'm not running much Rear %, only about 58.5%-59% at the start of the race, ending with about 56% (that's with no lead). Remember, I have a DW8 4 bar car, so the rear suspension is creating a large amount of mechanical leverage. Also, the tracks I've been running on the West Coast haven't been very dry. In fact, they've been so hooked up guys have been running out of tearoffs during the main events, the last couple of race. However, I have tested on some very dry tracks, and the shocks and chassis work very well.

As far as shock temps are concerned, I'll throw something out as "food for thought". If you're looking for the best way to keep shock temps down, and effectively keep the shocks from fading, the best liquid to use in the shocks is WATER. I know this sounds crazy, but all the top divisions use water where conditions require. For instance, asphalt tracks that require hard braking that over heat the brakes, wheels, tires, and shocks. The problem with water, it's very high maintenance and causes premature wear on the parts. This is not exactly a secret, but most of the top shock guys don't talk about it much, but if you bring it up to them, they probably will be impressed you know about it. Something to consider if you really need a radical solution to shock fade. I can refer you to a top shock guy in California that uses this on set up on shocks he does for top Nascar teams, if you're interested.

old racer
Member
posted July 28, 2003 01:37 PM     Click Here to See the Profile for old racer     
I tried the tiedowns on the right and easy ups on the left this weekend.

I think there is something there. The car was much faster through the center. It did wheelie more than I would like but I think that can be tuned out. I could run in the turn a lot harder and keep the momentum up through the center, I am going to play with this some more. Any one willing to talk about this yet?
I'll keep yall posted.
Good luck.


dirtracer14
Member
posted July 28, 2003 11:02 PM     Click Here to See the Profile for dirtracer14   Click Here to Email dirtracer14     
Funny thing that i decided to read this topic now i have been looking at my shocks a bit latly now that i have a handle on the car. I have seen shock fade from heat ...about the 115 to 120 range...pulled em off and put new ones on...big dif and same # shock. I also thought about wrapping the shocks with ice bags ...if you think about it what happens to the motor as the oil gets hot? same thing in the shock they just had a article in stock car or circle track that really shows how a shock works as it heats up oil gets thinner transfering threw the hole with less resistance. Now i also am on the west coast and see mostly tacky tracks....i have been wanting to go the other way with my shocks i want easy down to help really set the car for the turns... i can do it with the brakes and the car is fun to drive but after tearing the pushbar out of my car i was think the brakes were not the hot ticket.... so i am looking to drop the car fast when i lift without using the brakes....i am hoping to try it this weekend and see. Hey chad i would be interested in the water shocks thow the track im at tends to get rough some nights.

The best easy up shock is a 90/10.. Enjoy

Chad
Member
posted July 29, 2003 10:07 AM     Click Here to See the Profile for Chad   Click Here to Email Chad     
Dirtracer14- you can contact Mike Naake at Naake Motorsports. His website is www.naake.com He handles a lot of asphalt and dirt applications. He's located in Sacramento. The water as shock fluid is not very practical with respect to a weekly dirt racer, but talk to Mike, he'll get you up to speed.

Old racer- I too noticed how well the car gets into the corner with the right side tied down. You may even be able to drive in without lifting. I know it sounds crazy, but I routinely able to drive in without lifting or touching the brakes. It'll scare you the first few times, but it's really fast through the middle and off the turns. Talk about carrying your momentum and speed. Just remember that I drive a 4 bar car, so when the car rolls onto the RF, it induces the rear steer and helps the car turn. Suck it up and try to drive it in without lifting. You may be surprised (one way or another).

twister
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posted July 29, 2003 11:13 AM     Click Here to See the Profile for twister     
If you have all the weight transfered on the right side doesnt that make it lose forward bite coming off the turn?


old racer
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posted July 29, 2003 08:10 PM     Click Here to See the Profile for old racer     
Twister: In theory you are right, it should decrease forward bite. I think that we are increasing overall turn speed with this package and therefore not having to totally rely on killer forward bite. This my first experiment with this deal and I know I need some fine tuning but it showed a great deal of promise and enabled me to pass in the middle on the black slick where no one else was, only problem I had was guys trying to run in as deep as I did and pushing up into me. I think that most of us have put way to much importance on forward bite and lost focus of turn speed. I think that I will be able to go up a gear point when I get the car tuned properly and use the mile per hour and increased turn speed to make the car even faster.
Any thoughts?

Chad: Let me crawl before I walk,LOL. This is a real tight track that is surrounded by fence and no place to get out of trouble. I talked to some of my shock buddies and there are some guys doing glycol/water mix and some are trying glycerin. It's odd that shock guys don't want the average racer to know any of the new things going on. It's like pulling teeth to get them to open up and then you don't know if they are shooting straight. Shock guru's and head porter's have got to be related in some way. THEY are a strange group,LOL.

[This message has been edited by old racer (edited July 29, 2003).]

bachshute
Member
posted July 29, 2003 09:27 PM     Click Here to See the Profile for bachshute     
Old Racer:
I am working with shocks a little bit - havent been brave enough to try what you are though lol . I do know a couple of big late model teams that are having success with this on the tight tracks that get very slick ,
Anyway , after your post i may try it , is there any other adjustments needed when i try this or should i leave everything the same and just change the shocks ? Thanks for any help ,


Chad
Member
posted July 30, 2003 10:09 AM     Click Here to See the Profile for Chad   Click Here to Email Chad     
Bachshute- I have been running this shock set up and as mentioned above, it works very well. Just be aware that when you really drive it in deep, the car will roll quite a bit and very quickly. This will take you by surprise at first. It almost feels like the car's going to flip over, but you need to pick up the throttle right away and not lose the momentum. It's fast, but it'll take some getting used to. Like I've heard racers say: if the driver is comfortable, he's not going fast enough.

Twister- I realize what you're saying about losing forward bite, but I think alot depends on the rear end suspension configuration. My 4 link benefits from the car rolling over to the right, lifting the left side frame. This drastically increases the bar angles and generates mechanical leverage. Also, my bars are only 12.5" and 14.5" center to center, so small amounts of leftside body lift have a large effect on the bar angles and resulting force applied to the tire.

As for making and other adjustments when switching to the shock package, I didn't make any substantial changes, just tuned the panhard, Monte bar, and 4 link bars to changin track conditions like you would with any shock package.

bachshute
Member
posted July 30, 2003 03:36 PM     Click Here to See the Profile for bachshute     
Thanks Chad . I may not get to try it this week because i had to order the shocks and not sure if they will make it here in time , as soon as i get to try it i will let you know how it went . Thanks Again !!!


#13 mod
Member
posted August 03, 2003 07:37 PM     Click Here to See the Profile for #13 mod   Click Here to Email #13 mod     
Can you be a little more decriptive on this "tie down" trick. Will it work well on any mod? for example, we have a '02 2 link harris, and more corner speed is always good. Just don't forget faster isn't always quicker. We've been doing ok with what we have, but always looking for more. Can you help a rookie out? haha. 9th in the nation for IMCA points. Need to be faster.


WPP
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posted August 04, 2003 04:52 AM     Click Here to See the Profile for WPP   Click Here to Email WPP     
Do the shocks have to be the same valveing on each side like 30-50 on the the left can you have a 30-30 on the left rear


#13 mod
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posted August 04, 2003 05:17 AM     Click Here to See the Profile for #13 mod   Click Here to Email #13 mod     
We run Pro socks (93) on the rear. With 200 and 175 springs, sometime 175 and 150. depends on what the track is going to be like, but I am very open to new ideas. I'll try just about anything to go faster.


WPP
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posted August 04, 2003 05:38 AM     Click Here to See the Profile for WPP   Click Here to Email WPP     
I just thought with a 30-30 on lr the car may get back on the lr quicker but it may make the car push i have a friend that has a new rocket on a track that you need more side bite his tech boob said to add rounds to the lf and lr too add rake in the car it would get more side bite that was with tie downs on the rf and rr


Chad
Member
posted August 04, 2003 12:44 PM     Click Here to See the Profile for Chad   Click Here to Email Chad     
In response to the "tie down" working on a two-link, I'm not sure. Please understand that I run a 4-link. This is a different animal than the two-link. I used to run a two-link, but never tried the tie-down (didn't know about it). Give one of the reputable shock tech guys a call. I spoke with Bilstein's shock tech who's out of Southern California. By the way, he races a modified, and was very helpful in talking chassis and set up. Don't be afraid to try something, but make sure you understand what you're trying to accomplish before making a change. Lastly, consistency is the key to knowing if a change is better or worse. If you make a change and drive a different line or if the track is completely different, or if you throw in different chassis set up than usual, this will make the feedback useless. Give it a try and stay consistent.


Dman
Member
posted August 04, 2003 05:45 PM     Click Here to See the Profile for Dman     
Hey Chad,
What happens to the O in H2O when you put it in a shock and get it warm?I think your shock expert is pulling your chain.Unless he told you to use Glycol water mix to cool your shocks and you miss understood him.Water in shocks is like building your own little steam engine by using the friction from the valving for heat.I think if this were viable shock manufacturers would use it because it is cheaper than oil.The glycol/water mix in your radiator needs room to expand.Correct?What would happen in the shock?Maybe you could use some Alumiseal or Barsleak to prevent leakage.(just kidding!)Heat in a shock absorber is un-avoidable as they work via friction by restriction.Maybe someone can develop a fluid re-circulation system like is used in brake systems.Dman


old racer
Member
posted August 04, 2003 06:08 PM     Click Here to See the Profile for old racer     
My car is a DW 8 2 link with a 15" Lr link and a 20" RR link. It makes a lot of roll steer and it responded well to the shock package.
Good Luck


#13 mod
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posted August 04, 2003 07:38 PM     Click Here to See the Profile for #13 mod   Click Here to Email #13 mod     
So I'm willing to try the "tie down" thing for a night or part of one anyway. Can anyone fill me in on what you tie down to what? I got a 30-30 shock now to try too. Just need a little help with what to tie down to what? Thanks for all that help guys. It seems like we learn something new every week.


Chad
Member
posted August 05, 2003 10:28 AM     Click Here to See the Profile for Chad   Click Here to Email Chad     
The "tie down" refers to the shock having more rebound than compression, thereby making the shock slow the reaction of spring when it tries to spring back after it's been loaded. Consider what's happening in the suspension (on the RF): you go into the corner and the car rolls over and compresses the spring. The amount of compression you have in the shock determines how quickly the weight transfers to the RF and compresses the spring. Then when you get on the gas, if you have a lot of rebound in the shock, it will delay the spring from releasing its energy and keep it pinned or "tied down". Conversely, if the rebound is less than the compression, the shock is referred to as an "easy up" shock which would transfer the weight quicker off the spring. Many guys use this set up on the front shocks to get the weight transfered quickly to the rear tires to add in traction. Hope this helps and I didn't confuse you anymore. Please remember I'm not a chassis engineer or shock specialist, so if my explanation is a little off I apologize. I know how the shocks work, but it's just difficult to put everything down in a way someone else can understand.


#13 mod
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posted August 05, 2003 07:02 PM     Click Here to See the Profile for #13 mod   Click Here to Email #13 mod     
Thanks for the information Chad, we are going to try it tomorrow night in Oskaloosa. I also called Bill at Bilstein, haven't heard back yet. I'm interested to know what he has to say.


old racer
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posted August 07, 2003 08:47 PM     Click Here to See the Profile for old racer     
13: did you try it and what did you think?


#13 mod
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posted August 07, 2003 09:40 PM     Click Here to See the Profile for #13 mod   Click Here to Email #13 mod     
Hey-

We did try it, and I think that it's going to work. I think that our main problem is to soft of springs up front. The really problem is that we are not getting enough weight transfer to the rear from the front. We are going to up the spring rate for this weekend and see how it goes.
Still not fast enough. Bye the way I called bilstein and they have lots of things to try. It was worth the call.


worldcom
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posted August 08, 2003 07:03 AM     Click Here to See the Profile for worldcom     
Well, why don't you list the numbers they told you to try for shocks?


lucky13
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posted August 08, 2003 09:17 AM     Click Here to See the Profile for lucky13     
Any of you ever try 75-3 on RF? We have been running either 76-3, 75, or 76 depending on track condition. I'm not sure if a 5-3 will be enough. BTW-small metric, stock lowers, 2450 weight, Hoosier E-mod.

RE: Shock fade- I was recently talking to a racer that I respect very much (20+ feature wins every year) and he said the only reason he runs cheaper shocks (not monotube) is because they soften as the race goes on so as the track goes away, his car gets softer. I had thought of this before and it makes some sense to me. I am sure a lot of you have thought of this before. One thing though, your spring rate wouldn't fade, so wouldn't the car get jumpy?

Wow- over 1000 views!

[This message has been edited by lucky13 (edited August 08, 2003).]

#13 mod
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posted August 08, 2003 11:01 PM     Click Here to See the Profile for #13 mod   Click Here to Email #13 mod     
Bilstein's numbers were as follows, but remember we run a harris car which is an, out of the box, tight car. We also are running a 2 link car. We will be upgrade that old stuff next year for sure.

Well hears the numbers......

LF 650 coil/3050 shock
RF 700 coil/3050 shock
LR 175 coil/3030 shock
RR 200 coil/4040 shock

We are going to be trying the heavier front end this weekend, i will let everyone know how that works for us.

#13 mod
Member
posted August 10, 2003 03:11 PM     Click Here to See the Profile for #13 mod   Click Here to Email #13 mod     
Well we ran with the spring shock combo that I listed earlier. WOW, the car would run anywhere....We where making the move for 3rd, and got spun. Never the less, it's good to get the problem fixed.


Racer14K
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posted August 18, 2004 03:41 PM     Click Here to See the Profile for Racer14K   Click Here to Email Racer14K     
I was looking at some older posts on shocks and found this one. I was wondering if anyone has experimented anymore with these and what numbers should be used. I have just recently switched from 2 link to a 4 bar / swing arm 68-72 chevelle chassis and need shock ideas. Bilstein numbers would be a great help.


Chad
Member
posted August 19, 2004 09:06 AM     Click Here to See the Profile for Chad   Click Here to Email Chad     
To start:
Try 3050's on the left side and 5030 or 6030 on the RF and 5030 on RR. If the car drops too violently on entry, you can increase the compression on the LR and run 3060 or 3080 (you can even drop the rebound to 2060 or 2080).

Good luck.

sanderson10
Member
posted August 19, 2004 05:40 PM     Click Here to See the Profile for sanderson10     
Anyone have any tips and bilstien shock numbers for trying it on a 3 link suspension?

Jason

24KC
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posted August 19, 2004 05:55 PM     Click Here to See the Profile for 24KC     
Does anyone make an off the shelf shock for the left rear? All I can seem to find is tie downs, not an easy up for left rear. I have been running an easy up left front, tie down right rear. A couple of weeks I moved the radius rods in the rear 1 hole. Worked great if I was on the gas,if I lifted at all in the middle and left rear came off the bars look out wall. I want to try it again with a shock that will help hold left rear up. Any ideas?? Thanx KC


nolimit92
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posted August 19, 2004 08:32 PM     Click Here to See the Profile for nolimit92   Click Here to Email nolimit92     
Yes Bilstein make a 1040 shock for the LR. That is the shock we run anyway.


Mike


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