16 inch lr spring versus 20 inxh

[hunterracing]

What are affects of say goin from 16 175 lr to a 20 inch 175 I know the spring will compress the same but overall dynamically would it increase more drive bein taller?

[a25rjr]

Slightly. A loaded spring will make more traction than an unloaded one. Plus it will stay more consistent as it stays centered on the spring seat.

[hunterracing]

But if it's same rate would it be loaded more if it's taller or apply more pressure I understand putting same weight on each spring should compress same but is there another variable there

[Matt49]

Assuming you end up with the same static ride height, spring length does NOT matter unless you are coil-binding. That should never be an issue on the left rear. There is nothing to be gained or lost by changing LR spring length unless you want to talk about weight.

[hunterracing]

So would goin from 175 16 to say 125 or 150 20 inch have more dynamics drive bcs it bein preloaded so much more to get static ride height back

[JustAddDirt]

you can put an 11" 175 on there and you would see no difference.
as Matt49 says, as long as it is not coil binding.

I myself prefer the shortest spring I can get. less area for deformation, or bow in the spring leads to a smoother coil over, or coil over eliminator movement.
plus less coils less weight.

[hunterracing]

Kinda what I figured but I wanted see others opinions on this deal

[a25rjr]

The same rate spring only longer will not be any different.

Mr. Link and Mr. Bush will differ with you. Notice I said slightly.

[hunterracing]

Then what bout the really soft lr spring like 125 to 150 would that take some drive away bein softer or gain alittle bcs it's loaded so much static then still pushing as car lift dynamically

[let-r-eat]

SCD,

You saying Mark Bush is a dummy? Yeah right....

Did you read what you typed?

What are your qualifications? 6th place at Boone? A couple street stock wins? WOO wins? LUcas OIl? Nascar? Hooters Tour? NE Mods? SW Mods? ARCA? What are they?

[MasterSbilt_Racer]

If your ride height is the same and your spring rate is the same, a longer spring gains you nothing. It doesn't matter who you think said it. They are flat out wrong, or you misunderstood what was said.

[Matt49]

Mark Bush has forgotten more about vehicle dynamics than most of us will ever know. But mostly, he is very good at explaining things in a way that people can understand but without leaving out the technical details. That's a rare quality.

Spring length doesn't matter unless you start operating outside of Hook's Law. That is a fact and that is the end of the discussion about spring length.

The reason a softer LR creates more initial forward bite has nothing to do with LOAD and everything to do with what happens when the spring UNLOADS and the resulting change in left side bar angles.
If you have 800 pounds on a 200 pound spring, at ride height, that spring is compressed 4 inches. If you transfer 400 pounds OFF of that spring, it unloads 2 inches. Do the same thing with a 100 pound spring and it unloads twice the distance which increases bar angle. Obviously we limit travel with a chain but the speed at which we get to that point is dependent on the spring rate. Softer will travel a greater distance given the same amount of unloading.

[hunterracing]

But he has also said the stiffer springs gets the weight so wouldn't that apply on lr to get more drive instead of goin softer and stuff

[Matt49]

But he has also said the stiffer springs gets the weight so wouldn't that apply on lr to get more drive instead of goin softer and stuff

That rule goes somewhat out the window with LR spring behind setups.
It also goes out the window on soft RF setups due to camber gain and roll center migration.

The old "stiff spring get the weight" stuff is great for street stocks but with extremely dynamic setups like we have today on late models and even mods, there is a lot more going on. The concept is still important to understand but it's just one layer of the onion that has to be peeled back.

[hunterracing]

So would you gain more dynamics from 16 inch 175 to. 150 16 inch spring? Jst throwing ideas around I've even seen a car with the left lower bar always against the housing not gonna mention names but he wins a lot of usmts stuff

[Matt49]

Given the same amount of weight transfer, you'll have more suspension travel with a softer spring. This is true on any corner of the car whether weight is being transferred to the spring or from the spring.
The softer LR provides more forward bite ONLY while the spring is unloading because it is increasing left side bar angle faster than a heavier spring would. Once the spring is unloaded and/or the chain catches, the spring isn't doing anything. You are officially "barred up" and the stiffness of that corner of the car is way beyond what the spring could ever provide as long as your right foot is working.
A driver good at trail braking could race a car with NO left rear spring on it and would probably be the fastest thing on the race track.

[hunterracing]

So let's take this scenario you say car is barred up and Dnt need spring if you keep car up now that bein said when you drop the left lower bar that does what load the spring correct? Which tightens on throttle and also takes steer out?

[MasterSbilt_Racer]

So let's take this scenario you say car is barred up and Dnt need spring if you keep car up now that bein said when you drop the left lower bar that does what load the spring correct? Which tightens on throttle and also takes steer out?

When you drop the left lower bar, you decrease the wheel rate. It is the same as a softer spring.

[hunterracing]

But it takes steer out correct and how does is soften the spring? So if that's the case wouldn't you jst go ahead and soften the spring?

[a25rjr]

I'll attempt to explain part of my reasoning. Of the several drivers I have crew chiefed for, NONE have been able to keep the car on the bars at all times. There has always been 2-3 inches of spring compression past ride height. With that said, with the car on jack stands, on a short lr spring, and you let it down off the jack, you get that CLANG, when the spring hangs up momentarily on the upper seat. I know its instantaneous and ie believe it slightly disrupts the loading and ie traction of the lr. Can it be proven......don't know....it seems logical or its just one of my little quirks. I don't see how a spring flopping around could ever be a good thing.

[hunterracing]

You lost me on that one a25rj lol

[a25rjr]

You lost me on that one a25rj lol

LOL...I didn't proofread...see if it makes sense now.

[Matt49]

I'll attempt to explain part of my reasoning. Of the several drivers I have crew chiefed for, NONE have been able to keep the car on the bars at all times. There has always been 2-3 inches of spring compression past ride height. With that said, with the car on jack stands, on a short lr spring, and you let it down off the jack, you get that CLANG, when the spring hangs up momentarily on the upper seat. I know its instantaneous and ie believe it slightly disrupts the loading and ie traction of the lr. Can it be proven......don't know....it seems logical or its just one of my little quirks. I don't see how a spring flopping around could ever be a good thing.

I'm agree. Spring flopping around can't be good. Use these and you'll never have the CLANG problem again:
https://www.allstarperformance.com/product.htm?prod=750&part=ALL64201&add=no
We use one on the RR and one on the 5th coil. Yes your 5th coil will completely unload under deceleration and do this same CLANG thing on the race track. We finally noticed pretty severe wear on the coil-over adjuster nut that lead us to this conclusion but a Go-Pro would probably tell the tale. We don't use one on the LF because the spring is pre-loaded about 1/2 inch at full drop :-) That's another benefit of running a softer LR.
2-3 inches of LR spring compression past ride height under racing conditions should put that car straight into the wall. Not questioning what you're saying but are you sure that isn't from weaving around under caution to work the tires? The LR is the one shock that I never pay attention to the travel indicator for this reason.

[hunterracing]

How soft are you talking on lr there some say 175 is soft but goin to 150 or even 125 would be loaded so much even at full drop correct?

[a25rjr]

I'm agree. Spring flopping around can't be good. Use these and you'll never have the CLANG problem again:
https://www.allstarperformance.com/product.htm?prod=750&part=ALL64201&add=no
We use one on the RR and one on the 5th coil. Yes your 5th coil will completely unload under deceleration and do this same CLANG thing on the race track. We finally noticed pretty severe wear on the coil-over adjuster nut that lead us to this conclusion but a Go-Pro would probably tell the tale. We don't use one on the LF because the spring is pre-loaded about 1/2 inch at full drop :-) That's another benefit of running a softer LR.
2-3 inches of LR spring compression past ride height under racing conditions should put that car straight into the wall. Not questioning what you're saying but are you sure that isn't from weaving around under caution to work the tires? The LR is the one shock that I never pay attention to the travel indicator for this reason.
Aaahaa.....that will definitely fix the clang! We had a set on the last Rocket I crewed on but they weren't that long. Have they been out that long, I usually don't miss those type of things. My "library" stays up to date with the newest catalogs (its about kneehigh now,lol).

As far as the lr compression, you may be right. I guess I need to get the gopro hooked up. I haven't crew chiefed in year and a half, but I am in the middle of putting 2 cars together right now, a bwrc and a local built experimental car. It has a nascar style front end so we'll have to wait and see if it holds any promise.

[RaceMentally]

Longer spring same rate same darn thing. Longer spring less rate= car doesn't fall as easily, stays loaded, helps keep car on RF for corner entry blah blah blah. Throw a 125-150 on and keep 100-200lbs loaded at full hike and you're good to go. (Mic drop)

[Matt49]

Your a crew chief? Is that a paying position where you are?

As for the clang, zip tie the spring to the seat and it wont fall off and have to re seat itself. There should be no hang up. Sounds like your running lr spring and shock behind and a coil over kit on it? Ive never had a slider on the lr that would or could hang up on anything, whers or bsb.

Your 20 inch spring with the same rate on the lr will hang just as free as the shorter one did so it wont change your misfit of parts.

He's clearly talking about the UPPER seat "clanging". Obviously everybody wire ties their springs to the lower seat but if it comes off the upper, you're going to have this problem unless you use a take-up spring or something like the AllStar part that I linked him to.

[a25rjr]

Your a crew chief? Is that a paying position where you are?

As for the clang, zip tie the spring to the seat and it wont fall off and have to re seat itself. There should be no hang up. Sounds like your running lr spring and shock behind and a coil over kit on it? Ive never had a slider on the lr that would or could hang up on anything, whers or bsb.

Your 20 inch spring with the same rate on the lr will hang just as free as the shorter one did so it wont change your misfit of parts.

Please pm me your phone number so I can forward it to Mr. Link. Im sure he would like to discuss the $5000 set of shocks he sold me that you refer to as a "misfit of parts". Thank you.

[Matt49]

most people zip tie the spring on the RR to the cup on the TOP.. Its not needed by design on the LR because of the way most sliders are made. There are a few like allstar and afco with short upper spring cup seating areas and those need the spring zip tied to it and it runs smoothly up and down the slider shaft.. there would be no clang.

matt 49, Sorry bud this is the mod forum, you clearly don't know much about mods. a coil over slider protector isn't going to change much if anything on a lr slider, modifieds run 5 inch springs and most rules say one spring so no take up spring is allowed.

Everybody doesn't have that problem. To have that problem on the lr you would have to have over 2.5 of free hanging spring in your lr.

Now if he is running a coil over kit those do clunk on some because of the misfit around the shock eye nut, but most people run those on the rr like I already said in the post you quoted.

There have never been any clunks from free hanging springs on my car, its a matter of fitting your parts up right so when the upper spring cup on the rr goes to re seat it does so properly every single time. I modified my upper spring cups its not rocket science to figure out what is needed, to prevent the hang up.

Correct...not going to work on a slider...my bad.

[a25rjr]

712 867-5309

Im not sure why he would want to discuss anything with me, Ive never heard of him and could care less. Im more than positive by reading your posts on here its end user error on your part.

Again Ill ask is crew chief a paid position where you live? Where is that by the way?

Around me a lot of the top IMCA modified teams have paid crew chiefs and crew members.

There is no end user error on my part. I don't have those issues, been using longer springs and/or a stacked setup for several years. My post was sarcasm at its finest.

You let the cat out of the bag, when you admitted you don't know who Mr. Link is! I doubt there's very few racers who don't know who he is!

[Confused?]

I typically don't agree with SCD, but I have to here. I've been doing this foolishness for almost 30 years. I have never heard of this "Mr. Link" either. And to me, $5K for a set of shocks for a Mod is excessive.

[Matt49]

"Mr. Link" is Jerry Link. He's pretty well known and highly regarded in the shock world. Knowing or not knowing who he is doesn't really mean much though.

[Confused?]

LOL Ok, thanks

[oldtrackchamp4x]

Matt49. Thanks for posting that information. Only Link I know about is Jack Link the jerky guy. Lol JMO.

[a25rjr]

Sorry guys, Jerry is known more in the late model circles. When he was at Shy Suspension, his shocks won a ton of races and championships. Now he is the director of Afco's shock program. He can offer you mod guys a ton of info for your shock program.

[Matt49]

Not to change the subject...although the original topic has run its course...
Does anybody know anything about his new "Afco Technologies" shocks? The website says to call for more information but I'm not really in the market for new shocks, just curious about them.

[hunterracing]

Anyone played with bumpstops on a mod and how soft spring should it be to play with it without loosing drive off corner I know use to some would only let 2inches shaft showing

[RaceMentally]

$5000 set of shocks? You better have at least 12 of them for $5k or you're an idiot

[a25rjr]

$5000 set of shocks? You better have at least 12 of them for $5k or you're an idiot

Go price 6 shocks from Ohlins, JRI, or Penske......that's what you'll pay!

[TS3g]

If you race IMCA, you can get them for $50/ea :)

[Confused?]

^^^^^ Hahahaha. True

[racingjf9]

I have learned a heck of a lot in the last 7or8 years just reading scd post on here

[a25rjr]

I have learned a heck of a lot in the last 7or8 years just reading scd post on here

No doubt, he seems intelligent....he just rubs a lot of people the wrong way!

[let-r-eat]

Wish you the BEST stock car driver. Hope everything works out.

[RaceMentally]

Do you ever post anything factual?Jri base valve from bob harris $450 each newHence why I said 12 shocks haha. What's up with this dude? Stay outta the mod section with your DLM bs. $5k in a set of shocks. Fml this guys on some good stuff to be shelling out $5k for a set of shocks. I've got some $1,000 wheels that are lighter and IMCA stickered. You want to buy those too?!