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View Full Version : Rear spring rates for Fox body



David Love AI27
05-05-2007, 06:57 PM
I think my rear springs are to big (the car was built for drifting)... what rates are you Fox chasis guys running????

SmackDaddy
05-05-2007, 09:48 PM
FYI - 225lb and 275lb depending on the upcoming track event.

All depends on the other suspension parts though. One combination might not net the same or desired results as another one on a different Stang.

Spring rubbers can be the ticket also...especially during testing sessions.

GlennCMC70
05-05-2007, 11:10 PM
you need to give some front rate info. the springs need to be matched front to rear. for example, the 4th gens like a 3:1 ratio. that means if you have a 900 front rate, the rear needs to be around one 3rd of that (300). things that will affect that ratio are things like, rear sway bar size, rod ended or poly bushing rear control arms (changes roll rate), rear downforce, and personal driving ability and driving style. tire age is also a big factor in how well the car works. old tires make the car feel as if it has too much spring rate - it feels like it has no grip.
but even if you stick w/in, for example, the 3:1 ratio a 4th gen f-body likes, too much spring rate is a bad thing. your better off w/ too soft than too stiff.
so, unless you fill us in on what front rates you have that your trying to balance the rear rates too, there is no correct answer. i know guys running 1300 lb all the way down to 600 lb fronts on a 4th gen and 325 lb to 175 lb rear rates. getting the car to balance and be nuetral is what is key here.

push = too much rear grip. drop front rates or increase rear rates
overly loose = too much front grip drop rear rates or increase front rates.
dont exclude wheel spacers when tuning your set-up. they can be added to soften a given rate, removed to stiffen a given rate.

so, what is a good ratio w/ a Fox? i do not know. i'm sure the same rules apply and there is one. what is a good rear rate for a Fox? same again, who knows w/out front rate info.
mmmmmmmkkkkaaaaayyyy? :wink:

jeffburch
05-06-2007, 08:01 AM
Don't those things use a single pigtail 5.5" just like the f-cars in the rear?
Try the cheap streetstock dirt track springs from Day Motorsports online.
They come in 25# increments and are only like $45 each.
Come in 11 and 12 inch lengths.
http://www.daymotorsports.com/


jb

SmackDaddy
05-06-2007, 08:14 AM
From the H&R website:
http://www.hrsprings.com/site/about/manufacturing.html

Another issue that adds to the debate between "Linear" and "Progressive" rate springs, is that when most spring manufacturers say that their springs are progressive they are not! Springs may be wound progressively, but that does not mean that they function progressively. Some suspension springs are wound progressively but function as a linear spring. These springs can be called "dual-stage" coils, but are generally referred to as springs with "dead" or "inactive" coils. Dead or inactive coils are coils that are in contact with adjacent coils at loaded height.

Inactive coils do nothing but give the spring enough free-length to stay tight in the spring perches at full rebound (when the tires and wheels are hanging in the air like when the car is on a lift). A spring that is wound with inactive coils and no progressive coils that are active, is actually working as a linear-rate spring. This is why when you call a spring manufacturer for spring rates for your application you must ask, "What is the actual working spring rate?" This ensures that you do not just get numbers quoted from a design sheet.

For example: A design sheet may have rates of 69lbs. per inch, to 160lbs. per inch, to 220lbs. per inch. When the actual rate is 170lbs. per inch to 220lbs. per inch. As you can see, getting the correct information is important in making a true comparison.

[EV] Read the entire article to get you going and it has a lot of information in it. A lot factors come into play when addressing the Fox body suspension. Besides springs, struts, shocks, chassis stiffness and other geometrical parts, don't forget the TIRES! They are the secondary set of springs on the car!! Set the pressue too high and you just made a nice susupension setup into garbage. Set the pressure too low and it will be more than a handful! Keep this in mind....all the time.

GlennCMC70
05-06-2007, 08:28 AM
you shouldnt use a progressive rate spring in a racing application.
although some progressive rate springs will use up all its progressive section from just the weight of the car alone. in that case, they are o.k., but i would avoid them if at all possible.
stick to a linear spring.

SmackDaddy
05-06-2007, 10:08 AM
you shouldnt use a progressive rate spring in a racing application.
although some progressive rate springs will use up all its progressive section from just the weight of the car alone. in that case, they are o.k., but i would avoid them if at all possible.
stick to a linear spring.

2nd that one for sure.

Rob Liebbe
05-06-2007, 09:46 PM
Too much rear spring in the back can be very bad. Well more correctly put an improper front to rear suspension stiffness ratio is bad. Too stiff in the rear can give the undesireable snap "oversteer" that sent me off of Hallet #1. That was with the H&R Race spring set. The rear was way too stiff. I ended up keeping the H&R Race springs in the front and use a set of Eibach street (10% stiffer than stock) in the rear as well as a stock GT front and rear sway bar setup. So many factors go into this as Glenn has stated. I think that my H&R problem was linked to the fact that the car is a stripped down race car with a lot less weight on the rear than a street car. My street/track car with full interior and spare tire in place never had any problems running a very similar suspension setup with H&R Race Springs but it still has a lot of weight on the rear. That's my theory anyway.

You're doing the right thing by asking. Keep asking and also trying different things. Just go conservative on rear rate. And remember, the Camaros don't have anywhere near the rear suspension bind that the Mustangs do. This will change the 3:1 ratio that Glenn stated. Crappy Mustang rear suspension!!!!!

Best of Luck. Call if you want to talk more - early evenings and weekends are best.

Boudy
05-06-2007, 09:54 PM
David: I am currently running linear springs at 900 lb front and 200 lb rear. Not sure if they are right or wrong but that's what it came with and now that the front end is a couple inches wider and the rear is not slapping 1" side to side, it feels pretty good. I was loose on exit @ TWS and RP suggested I remove the rear sway bar which worked well.

Hopefully this summer will lend some time to test other combinations.

Rob: I've got a rotor for you. Thanks.

Boudy

GlennCMC70
05-06-2007, 10:35 PM
i've heard Robs means of setting up spring rates all too often. you guys are aware that jumping up and down just 25lbs in the rear rate is a considerable move, right? by limiting yourself to H&R, or Eibach, or MM springs, your moving all over the map in front or rear rates.
why do you guys not get what you need from the dirt track shops in specific rates? we sell off what we dont need at almost zero loss so there is no major risk to doing this.
just wondering.

David Love AI27
05-06-2007, 11:53 PM
Thanks guys!! I think the springs I have are around 400lbs which would explain the loose condition... I'll check the fronts and look at the 3:1 ratios... may not be able to correct before Hallett but all this info will help my decisions in the near future... Check out other issues on other posts... Thanks again you guys are great... you might be kicking you own butts when Jason passes you in 2008......... :twisted:

mitchntx
05-07-2007, 07:00 AM
Last November I got a note in my e-mail box that pitstopusa.com was reducing their spring inventory and was selling AFCO 5.5" pigtail x 11" springs for $29 each in rates starting at 125 lbs and going to 350 lbs in 25 lb increments.

So, I bought several pairs in increasing rates

David, I have a pair of 250s and 275s I would sell you pretty cheap if you'd like them.

SmackDaddy
05-07-2007, 07:10 AM
Some great information is to be had in this thread. One note of caution - if you work on getting rear grip and make changes to do so, the outcome with a sticky rear will be a Mustang that pushes and plows through a corner. It's a fine balance between having enough or too much rear grip when matching it up with the front. I tend to like a slightly loose condition which can be driven through during corner exit. A push will result in having to lift on exit which will slow ya down... a lot!

Don't forgot the front when changing the rear.

Testing: being consistent enough on corner entrance, apex and exit to know whether or not chang "A" made more of a difference than change "B" is paramount.

I'm always available to help test setups if the price is right. You know.. big glass of ice tea or lemonade. :D

mitchntx
05-07-2007, 08:12 AM
Most definitely ... testing has to remove as many variables as possible. Be consistent on air pressure, shock settings, fuel load, etc. It all adds up.

And sometimes, you will find that a 25lb change is too much of a change and going back isn't just right either.

There are CMC legal ways to split hairs, like with bushing material or wheel spacers.

GlennCMC70
05-07-2007, 08:23 AM
I'll check the fronts and look at the 3:1 ratios...

David, remember, i used the 3:1 ratio as an example for what works w/ the 4th gen f-body. due to differences in suspension design and geometry i'm sure thats not the correct ratio for a fox ford. yours could be a 2:1 or a 5:1, i just do not know.
Roberts cars set-up shows about a 4.25:1 ratio. he is also the only one who has posted front and rear rates.

SmackDaddy
05-07-2007, 08:44 AM
IMHO 900lb front springs are too much. Then again, it all depends on the other 101 things involved when setting up the suspension.

700/225 seemed really close - but again, it all goes along with everything else as a whole.

Example: MSRC 700/225 the car had a huge push and nothing could be done at the time - even with tire pressure. Next MSRC event. Went with the 700/275 setup and the car was wicked loose (no changes to front suspension). With a change to the front suspension, it went from loose to slight oversteer.

Factors involved:
Tire pressure(s)
Front/rear swaybar and bushings
Strut/shock rebound rate
Weight distribution
Chassis flex
Big factor - driver's ability to hit all marks consistently

.02

jeffburch
05-07-2007, 10:00 AM
Just my .02

I would never make changes to the wrong end of the car.
If the front is doing something undesirable, make changes at the front.

Don't take away grip you have at one end just because the other end has less.

jb

SmackDaddy
05-07-2007, 10:09 AM
Harmony is that elusive pot-o-gold.

GlennCMC70
05-07-2007, 10:14 AM
Just my .02

I would never make changes to the wrong end of the car.
If the front is doing something undesirable, make changes at the front.

Don't take away grip you have at one end just because the other end has less.

jb

that is true for a car that is almost balanced or is balanced. but if you are just way way off (soft) on rear rates and the front is spot on, the car will still push. softening the front will make the push go way, but the car should be faster if you were to stiffen the rear. overall, you have to work the problem. sounds to me like David has way to stiff of a spring on the rear and no idea whats on the front. but guessing from the rears, i would think 900-1000 is what he will find.
Davids best bet for now is the copy another drivers set-up and then work it from there.

Al Fernandez
05-07-2007, 01:32 PM
Ah but which driver to copy? :lol:

It seems to be common perception that some guys are fast thanks to their cars..but my experience is that its just as likely to be that some guys are fast in spite of their cars. Some guys just aint fast. 8)

My point is, Glenn is right, find some basline from which to start and then experiment from there. There is no "right" answer, and what is fast for you might not be fast for someone else. I've driven some cars that I thought were awful but their owner liked it, knew it, and ran fast with it. I've also driven a few that I thought were fabulous who'se owners thought were completely off the mark.

SmackDaddy
05-07-2007, 01:40 PM
The driver "MUST" know what is going on in order to have any idea of what to change or adjust. Thinking that the car is pushing due to an incorrect suspension setup when actually they are driving into a corner waaay too fast leads to nowhere.

A car + 2 seats = priceless

GlennCMC70
05-07-2007, 02:11 PM
you have to be confident in the car before you are willing to drive it fast.

SmackDaddy
05-07-2007, 02:52 PM
you have to be confident in the car before you are willing to drive it fast.

Instructed many green students? hehe :D

GlennCMC70
05-07-2007, 03:04 PM
seafoam green to be exact.

Boudy
05-07-2007, 06:05 PM
The driver "MUST" know what is going on in order to have any idea of what to change or adjust. Thinking that the car is pushing due to an incorrect suspension setup when actually they are driving into a corner waaay too fast leads to nowhere.

A car + 2 seats = priceless

My car just received a second seat for that very reason. :wink:

Boudy

jeffburch
05-07-2007, 07:14 PM
Me too.
<licks chops>

jb

marshall_mosty
05-07-2007, 07:47 PM
Guys,
Remember when people start talking about front/rear ratios, the actual wheel rate of the setup may be vastly different.

Since the Mustang front spring is set so far inboard from the wheel and strut, it takes a huge front spring to act the same as what would be on a 4th gen Camaro or AI Mustang which has coilovers.

The same holds true in the rear. The closer to the axle (or behind) you get the spring, the less lb-in rate you will need to get the same effective wheel rate.

Mustang Front Motion Ratio
Conventional = .25
Coil-over = .9

Mustang Rear Motion Ratio
Conventional = .49
Coil-over = 1.1


CMC Mustang with H&R “Race (Red)” springs
Front: 750 lb-in (at spring) = 188 lb-in (wheel rate)
Rear: 260 lb-in (at spring) = 132 lb-in (wheel rate)
= 1.42/1 Front/Rear split

AI Mustang with coilovers and T/A
Front: 450 lb-in (at spring) = 405 lb-in (wheel rate)
Rear: 350 lb-in (at spring) = 385 lb-in (wheel rate)
= 1.05/1 Front/Rear split


As shown above, if you are running a T/A car (AI or Cambird) your front/rear split will be much less than a CMC Mustang which has a bunch of "built in" bind with the 4-link design. The T/A cars need less split (more rear spring rate) due to less rear bind (geometrical and bushings) which will now need to be accounted for by a higher spring rate.

mitchntx
05-07-2007, 08:42 PM
Good info, Marshall.

You are correct in your thoughts about "effective" rate which is dependent upon a lot of differing factors, like wheel offset, bushing material and even air pressure in the tires, which changes dramatically during a 20 minute race.

Factor in lessening fuel load, head wind down force.

However, the suspension pick up points on ANY CMC platform is fixed and a known. So once one figures out where the "balance" is, chassis design plays a lesser role.

Rob Liebbe
05-07-2007, 09:28 PM
I don't know if David's head is spinning, but mine is.

To answer Glenn's question about why I mix n matched spring manufacturers. I knew I had too much rear spring, I had a set of Eibachs laying around, I called Eibach to get an idea about what rate they were, they were much softer than the H&R rears, so I tried them. Pretty scientific - huh? That got me into the gross ballpark (luckily) and now I can tune it in with adjustable shocks, tire pressure, steering strategy, throttle strategy, downshift - upshift strategy, rev limiter strategy, front sway bar end link tension, water leaking from my cool shirt cooler, overaggressive driving, etc., etc., etc.

Get someone else to ride and drive the car at a more relaxed event like TWS Motorsports Club. There is a lot of talent and experience here to help you along. My advice is to set the car up with a bit of a push and work toward the loose condition slowly.

David Love AI27
05-07-2007, 11:18 PM
Big factor - driver's ability to hit all marks consistently

.02


I'M SCREWED!!! :( WHERE ARE THESE MARKS YOU SPEAK OF?!?! :shock: ONLY MARK I AM FAMILIAR WITH IS THE BIG YELLOW SQUARE BETWEEN 1 & 2 AT TWS.....

tried to hit that square going CW... didn't work too well :wink:

I kid... I understand what you are saying...

David Love AI27
05-07-2007, 11:27 PM
[quote="GlennCMC70Davids best bet for now is the copy another drivers set-up and then work it from there.[/quote]

Honestly... this is what I was looking for..

you all have to remember that I purchased the car from a guy who knew NOTHING about car setup... he tried to setup for drifting but didn't even know that it had a 2.73 gear, I have a 3.27 in it know and can kick the ass end around pretty good imagine what it will do with my 3.55 or a 3.75...

Guess what I'm learing about suspensions is... everyone likes something different and there are MANY ways to adjust...

Thanks again

David Love AI27
05-07-2007, 11:30 PM
The driver "MUST" know what is going on in order to have any idea of what to change or adjust. Thinking that the car is pushing due to an incorrect suspension setup when actually they are driving into a corner waaay too fast leads to nowhere.

A car + 2 seats = priceless

installed 2nd seat for just that reason

mitchntx
05-08-2007, 05:43 AM
Guess what I'm learing about suspensions is...

Wait till you try and understand roll center .... :shock:

Al Fernandez
05-08-2007, 02:31 PM
I'M SCREWED!!! WHERE ARE THESE MARKS YOU SPEAK OF?!?!

Well, I know turn 6 at TWS going CW has marks at turn in, and the apex. Both are on the left side of the track though, so even those are confusing since you "hit" one but not the other. :lol: :lol:

oz98cobra
05-08-2007, 04:19 PM
Guess what I'm learing about suspensions is...

Wait till you try and understand roll center .... :shock:

He needs to understand roll center if he wants to make his CMC Mustang handle!

PM sent David - I don't want to share my secrets with all these GM guys :wink:

Todd Covini
05-09-2007, 01:19 AM
I'll share secrets.

10+ years ago many of the CMC folk were wrestling with this very question.
Global West was a primary sponsor for CMC at the time.
They worked closely with many of the drivers...who went the full range of linear rate springs. (Most of us were too low and too stiff, a common misconception....Suspension travel is your friend.)

The Global West "Blaine Butler Setup" was winning races at the current GM frequency in a notchback Fox. We all copied, used that baseline...and all got faster. (Much like all of our guys are now, here in Texas.)

900 front/ 200 rear (personally, I'm at 190 rear)
Koni adjustables all around and a day of testing to play with shock valving.

...and driver preference/comfort level will vary, as mentioned.

-=- Todd

PS- Where is Micah? We need some expertise on Roll Center???

Todd Covini
05-09-2007, 01:35 AM
I'M SCREWED!!! WHERE ARE THESE MARKS YOU SPEAK OF?!?!

Well, I know turn 6 at TWS going CW has marks at turn in, and the apex. Both are on the left side of the track though, so even those are confusing since you "hit" one but not the other. :lol: :lol:

Heeyyyyyyy...there was a bright yellow Mustang and a black Mustang with a white hood right in the spot where I needed to be when I got there... at the apex. Kinda had to go around! :twisted:

mitchntx
05-09-2007, 07:05 AM
I'M SCREWED!!! WHERE ARE THESE MARKS YOU SPEAK OF?!?!

Well, I know turn 6 at TWS going CW has marks at turn in, and the apex. Both are on the left side of the track though, so even those are confusing since you "hit" one but not the other. :lol: :lol:

Heeyyyyyyy...there was a bright yellow Mustang and a black Mustang with a white hood right in the spot where I needed to be when I got there... at the apex. Kinda had to go around! :twisted:

Please explain the term "apex" as it applies to the attached photo?

Boudy
05-09-2007, 10:57 AM
Oh, Mitch... Stop splitting hairs. We all know that Todd uses a dynamic apex. You know, the one that shifts to fit the story being told. :lol:

Boudy

Adam Ginsberg
05-09-2007, 02:24 PM
We all know that Todd uses a dynamic apex. You know, the one that shifts to fit the story being told. :lol:

He is in management, afterall.

Todd Covini
05-10-2007, 01:30 PM
Mitch,
Photoshop Corey's car at the Apex (where the dark pavement is) and you'll see where I was going. :roll:

Adam...you stay quiet. :D

-=- T

mitchntx
05-10-2007, 04:27 PM
OK ... this was the "Corey Line"

http://www.argentlab.com/nasatx/mitch/CoreyLine1.jpg

What's your point?

Adam Ginsberg
05-10-2007, 05:05 PM
Corey's car is facing the wrong way, although it's track placement is correct.

GlennCMC70
05-10-2007, 05:15 PM
Corey's car is facing the wrong way, although it's track placement is correct.

uuummmm, if you would come race w/us, you would know we ran TWS CW this past time.

Adam Ginsberg
05-10-2007, 06:20 PM
uuummmm, if you would come race w/us, you would know we ran TWS CW this past time.

Ummm...you didn't get the joke.

mitchntx
05-10-2007, 06:24 PM
You know ... I would have expected more from a series director.

GlennCMC70
05-10-2007, 06:27 PM
go away spinny, this isnt AICMCIDAHO.com :P

jeffburch
05-10-2007, 08:07 PM
You know ... I would have expected more from a series director.

Seriously.

jb

GlennCMC70
05-10-2007, 08:12 PM
well lower your expectations. :P

oz98cobra
05-14-2007, 03:26 PM
I'll share secrets.

10+ years ago many of the CMC folk were wrestling with this very question.
Global West was a primary sponsor for CMC at the time.
They worked closely with many of the drivers...who went the full range of linear rate springs. (Most of us were too low and too stiff, a common misconception....Suspension travel is your friend.)

The Global West "Blaine Butler Setup" was winning races at the current GM frequency in a notchback Fox. We all copied, used that baseline...and all got faster. (Much like all of our guys are now, here in Texas.)

900 front/ 200 rear (personally, I'm at 190 rear)
Koni adjustables all around and a day of testing to play with shock valving.
...

OK, I'll share ... a little ...

So why can't this "winning formula" of old work today? Consider this - the setup you mention above keeps the ride height high, with not inconsiderable body roll, lots of chasis flex, and poor camber control - which was countered with bags of static camber - this worked because with a high ride height, at least the roll center is above ground, and the body roll helped minimize the bind inherent with the 4 link - the car was reasonably easy to drive fast for a driver of average experience.

I drove Eric's old #17 on Saturday, and it pretty much fit this model - the car felt good and was easy to drive, but I doubt I could set as fast a lap time in it as I could in Adam's #5 for example? #17 would be perfect for a rookie to intemediate racer without changing a thing!

But I don't think this setup will cut it today if you want to win races - to beat those speedy highly developed GM boys, you need to lower your ride height as much as you can, stiffen the chassis as much as possible (in other words, ditch that bendy bolt in cage) stiffen the front springs way way up (and downsize that big ole front bar to compensate) - then tune the rear end to work with the front, which will still be relatively soft in the spring dept.

Yes the roll center will be below ground (and if the CMC directors wanted to change one simple rule to update the "parity" with the GMs, I suggest allowing X2 balljoints to help with this), but the stiff springs and chassis will help offset the negative effects of the low roll center plus help with camber control - but most importantly, the lower ride height now means we can go around corners faster. When tuning the suspension, focus on what the car is doing from mid corner to corner exit - what happens on the way in is somewhat less important (it's a Mustang after all, they all feel like crap on turn in!), but you need to be able to get on the gas early and not have an inherent corner exit push.

This setup may be comparitively more difficult to drive - for example, it won't be so forgiving if you miss a turn in point or turn in a little too hot - but it will reward a capable driver with constently faster times - and just as importantly, it should get out of corners closer to the torque arm equiped GMs, and because the stiffer springs enable you to reduce the static camber somewhat, you should be able to brake with them as well!

GlennCMC70
05-14-2007, 03:58 PM
Daron is right about that camber, too much and you give up alot of braking. i'm slowly dialing out camber and dialing in caster, all the while increasing front grip in the corner and under braking. i'll also be announcing a custom bushing to aid in this.

so, lots of camber to make up for soft rates that gives body roll in turn gives camber loss. and lots of camber causes less stopping ability.
sounds like a dog chasing his tail to me. something needs to give. control body roll. how? buy upping spring rates and or sway bars. if there is not enough sway bar available from the factory offerings, make it up in spring rates.

interesting info Daron, thanks.

SmackDaddy
05-14-2007, 06:38 PM
It's easy to explain how to get to mars. Getting there is another story.

Someone needs to step up and apply the theory.

Anyone? Hello??

This thing on? :lol: :lol: :lol: :lol:

GlennCMC70
05-14-2007, 06:46 PM
It's easy to explain how to get to mars. Getting there is another story.

Camber and lack of braking? Hmmm... good thing 17 has lots of camber so it can outbrake everyone. Whew! Glad we got that cleared up. :D Yes, even #70 doesn't stand a chance...especially T16 in Houston. 8) 8)

so what is it, ford = better or gm = better, i'm not following your mood swings.
and as for T16, well part of getting into it, is being sure you can get out of it. sorry, you left that door open.

SmackDaddy
05-14-2007, 07:00 PM
It's easy to explain how to get to mars. Getting there is another story.

Camber and lack of braking? Hmmm... good thing 17 has lots of camber so it can outbrake everyone. Whew! Glad we got that cleared up. :D Yes, even #70 doesn't stand a chance...especially T16 in Houston. 8) 8)

so what is it, ford = better or gm = better, i'm not following your mood swings.
and as for T16, well part of getting into it, is being sure you can get out of it. sorry, you left that door open.

They make medication that can help you with those mood swings. :D

GM's suck at braking, but that's about it. You guys get all out of control and not sure if it's the car or driver. lol

You collective - attached at the hip types need to get together and build a Mustang. Sounds like you guys have it all figured out on paper. Good luck to ya. <snickers>

GlennCMC70
05-14-2007, 07:03 PM
yep, your the man. i'll send the media your way.

SmackDaddy
05-14-2007, 07:07 PM
They've been all over trying to find that "Verner" guy. No luck thus far.

Yep.. I didn't need T-shirts to tell me that either. roflol <I kiiiiid!!>

Mars! Lets go to Mars!! Who's the captain? :lol: :lol:

Todd Covini
05-15-2007, 08:00 PM
Ok girls break it up....back on topic.

Daron...you're correct, that setup is definately "old school". I've played with the setup you've explained...lowered it...stiffened up...played with roll center...had a torque arm (they were legal for a season or two way back when)...spring rates....panhard bar....locker rear...worked camber from 2.5 degrees out to 4 degrees and back again....blah...blah...blah.

In the end, the fastest setup (FOR ME) was what I have.
It's the lowest maintenance...universal setup for every track I go to.
Sure...I know I'm leaving something on the table by not tuning to each track I go to. But (FOR ME), not having to work on the car and having consistent top 5s is more important than a few wins...and a few 10ths.

I commend all of the Texas CMC drivers for working so hard on their setups. This is what has made this group so fast and stand out to the rest of the country! Keep it up! But for me....I'll stick to the tried & true...tweak a bit as the car hopefully comes back together....and continue to give any top 3 cars a run for their money, whenever I come back!!!

-=- Todd

PS- Watch NASCAR at Sears Point (Infineon) some day. Those guys have figured out how to make pigs of cars roll & bite on a road course. It ain't pretty...but it sure is fast.

Boudy
05-15-2007, 10:25 PM
Someone needs to step up and apply the theory.

Anyone? Hello??

This thing on? :lol: :lol: :lol: :lol:

Just hold on a minute. If these cars have been developed to full potential, as I'm being told, then someone here has test data to support or refute Daron's suggestion.

Anyone? Hello???

This thing on?

Sorry but sarcasm and "I tried but it didn't work for me" just doesn't make cars faster. Give data, proof, or even simple logic to support your statements for dirt's sake. Those of us left behind don't really want to waste money testing when test data is out there. I respect your opinion but damn, give something that supports it. If rule changes are truely needed then fine but we can't storm the gate claiming, "Cause we say so."

Boudy

marshall_mosty
05-16-2007, 01:48 AM
Boudy,
I think the "magic number" is actually a range. Everyone could easily conclude that a Mustang with super soft or ultra stiff hooptie suspension won't work well for W2W racing. That narrows down the tuning a bit. You can return the hydraulics I know you were keeping your eye on.

A given platform will work well with a range of "fine" settings once you get the "rough" setting correct.

The rough setting would be something like:
1. Get car down to 3150 (for a Mustang)

2. Try and push as much weight to the center of the car... and low (within ballast constraints, etc.)

3. Stiffen the car to the hilt (good subframe connectors, well built welded-in cage)

4. Buy a proven suspension setup for the rear (Griggs or MM)

5. Get the track width as wide as possible (SN95 front arms with 96+ spindles in the front and SN95 axles in the rear)

6. Get the front track as far forward as possible using offset delrin bushings.

7. Get a good set of struts/shocks (probably either Koni DA's or Bilstein Race Valve)

8. Bump steer the car

9. Corner weight with as much adjustment as you can (rubber or polyurethane spring insulators as "legal" spacers for both front and rear springs)

10. **my opinion** run a small front bar (4 cyl) and a stiffer spring up front.

11. Run a good set of rear lower control arms with a spherical bearing at one end (MM has a set). This will reduce some of the bind in the stock 4-link rear suspension.

12. Have the car aligned properly to maximize tire contact patch in the front during braking (as Glenn said, try and dial out as much negative camber as the car will let you. This will help braking but hurt corner speeds... fine line)

13. Run a "legal" front splitter or air dam (Ranger air dam works very well for a $25 piece of plastic)

14. Box the radiator so you can limit the air flowing around the radiator. This will maximize cooling and allow you to close down the open area in the front of the car, reducing drag (think NASCAR qualifying with all the tape over their radiators to decrease aero drag)

15. Within the rules, try and get the front fenders as far out as you can to divert the air around the front tire instead of having the air hit it head-on.

16. Choose a brake pad that suits your driving style (initial bite and release characteristics are key)

17. Adjust your brake proportioning valve to keep the car balanced when trail braking.



I didn't mention anything about actual spring rates. That's a black art that Glenn and Mitch have worked out nicely for their cars. Finding the right spring rate for a given platform (including driver) is just a go to the track and drive... change springs and drive again... repeat.... affair.

If I were to suggest a starting point for springs (outside the CMC box and coming from an AI guy) I'd say that the H&R "super race" front springs with a "sport" rear spring would be a good starting point given the amount of weight removed from a factory trunk area is larger than the amount from the engine bay (by percentage)... however, this is just my opinion.

Fine tuning would be :

1. Tire pressures
2. Sway bar end link preload
3. Rear end differential choice
4. Rear end gear ratio choice
5. Sneaky Pete NOS system
6. Driving style

I can't think of anything else on the car at this point unless you want to make the car super slippery with umpteen coats of Zaino... wait... that's Glenn's secret to sucess!!!

donovan
05-16-2007, 07:45 AM
...

donovan
05-16-2007, 08:14 AM
EV, get off your high horse...

You are a good driver, but your car was not developed fully. Get over it.

I use to have a lot of respect for you, but as of lately you are just nauseating.

It’s too bad you had too much pride to ask people for help or discuss your Mustangs inability to keep up.

The obvious answer is that you did not have the time, money, ambitions or ability to finish the job. I know it’s hard to admit with all the pride you have, but we all know it’s true.

It’s okay to admit it. It will only make you stronger and people will respect you more.

DD

AllZWay
05-16-2007, 08:22 AM
I can't think of anything else on the car at this point unless you want to make the car super slippery with umpteen coats of Zaino... wait... that's Glenn's secret to sucess!!!

He is the "king of bling". :D

GlennCMC70
05-16-2007, 08:23 AM
in order to help each other out w/ set-up info, you guys have got to stop refering to springs by things like "H&R super race" and "sport" and start refering to the specific rates. just bumping up or down from say a 200lb rear to a 225 lb rear is a big move. but 25 lbs could be the difference between driving style. you gotta find what works for you and what works for you will change as your driving gets better. i've made more single changes to my car this year than any other single season.

Rob Liebbe
05-16-2007, 08:24 AM
Don't forget seat time! Glenn and Jeff have tons, Proctor has a lot in a different type of car, Todd has a lot, I have a lot, Verner had a lot, etc. Don't forget that racing IS indeed different than open tracking. I didn't believe that was true until I made the switch, but being really comfortable in the car, knowing its characteristics/limits/dimension and being in control at all times is the first step and also key to driving any setup. Todd's car is a good example of a car that requires attention to rear end control (his gastrointenstinal control is another issue altogether). He has adapted his driving style and can overcome that characteristic through lots of time in that car. Chris Lyons drove my car once and his response was that he didn't know how I could drive the POS. My point is seat time is invaluable. I can't imagine what it would be like to jump into the piranha pit tha tis Texas CMC as a pure rookie.

GlennCMC70
05-16-2007, 08:28 AM
I can't think of anything else on the car at this point unless you want to make the car super slippery with umpteen coats of Zaino... wait... that's Glenn's secret to sucess!!!

He is the "king of bling". :D

that was before rehab, dont open old wounds please. :wink:

mitchntx
05-16-2007, 01:08 PM
Don't forget that racing IS indeed different than open tracking. I didn't believe that was true until I made the switch, but being really comfortable in the car, knowing its characteristics/limits/dimension and being in control at all times is the first step and also key to driving any setup.


I'm beginning to think that folks like you and Adam attended HPDEs for a different reason than I did. The move to wheel to wheel was not that big of an issue for me.

I was all he time tweaking, messing, fiddling and searching trying to get another tenth. All of us weren't racing, but over dinner, there were some bragging rights being handed out.

AllZWay
05-16-2007, 01:17 PM
Mitch is dead on.... Hell we were racing amongst ourselves and I think each of us were warned by Rick, NASA and the like that we needed to move to wheel to wheel or tone it down. :lol:

To me the jump from OT to w2w was really nothing at all..... it just allowed for more places to pass....which is one aspect I still have the most to learn and I keep getting my arse handed to me. :oops:

GlennCMC70
05-16-2007, 01:23 PM
i had 5 years of seat time before i came to CMC. that was 3-4 weekends a year. i'm now doing 5-7 weekends a year for the last 2.5 years. that is alot of seat time. and it has made the biggest improvement in my driving in the last year or so.
so guys that are finishing mid pack and farther back, my guess is you didnt have alot of seat time before coming to CMC. thats fine, but that leaves a big disparity between ability that you guys will soon be closing the gap on. w/ our current crop of drivers, TX CMC will be just that - a piranha pit in the next year or two.
man, those poor new guys that are coming in soon. wow. :shock:

marshall_mosty
05-16-2007, 02:48 PM
I'm beginning to think that folks like you and Adam attended HPDEs for a different reason than I did. The move to wheel to wheel was not that big of an issue for me.


HPDE... what's that. I started in Racecraft! 8)

GlennCMC70
05-16-2007, 03:21 PM
I'm beginning to think that folks like you and Adam attended HPDEs for a different reason than I did. The move to wheel to wheel was not that big of an issue for me.


HPDE... what's that. I started in Racecraft! 8)

< in my best redneck voice > well dare's yur problum!
sorry Marshall. :P

marshall_mosty
05-16-2007, 05:56 PM
< in my best redneck voice > well dare's yur problum!
sorry Marshall. :P


Ohh well... I guess I went straigt for the crack habit instead of wasting time on softer stuff. 8)

GlennCMC70
05-16-2007, 06:55 PM
i see it as being a recreational user who stepped up to hard core user. :shock: