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M-5300-P springs for LS questions

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1) Has anybody actually measured the height of this spring. I pulled the rear springs out of my LS this evening. The Part # is CR33-5560-TA. I haven't had any luck find any info on the LS spring. I'm planning on ordering a set of the M-5300-P just for the sole purpose trying a lower stance for performance. (I'm putting on MM Camber plates and have to pull the springs out anyway.)

2) Has anybody with an LS tried the P's with their original struts? I'm trying to determine if I have to purchase the strut mounts but thinking I don't as the LS has different struts than a GT?

Thanks.
 
Have you read this thread? Everything in there should apply to your car. The P springs will lower your car about 1" in the rear and 1/8" in the front.

https://trackmustangsonline.com/boss-302-technical-forum/ford-racing-suspension-upgrades/
 
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Yes. I read Cloud 9's thread as well.

I didn't see anybody talking about an LS. (Plus I read comments about the cars not being "Laguna Feca's" so that leads one to think that the suspension is somehow a little different.) Pe

Then I spent another hour digging around and found this about differences in the LS:

"Engine power routes through a six-speed close-ratio manual gearbox to a standard 3.73-ratio Torsen limited-slip differential, helping the revised rear suspension deliver maximum torque and traction under the punishing conditions encountered on the track.

Higher spring rates and a larger rear stabilizer bar – all upgraded over Boss specifications – help generate unrelenting grip. And drivers can dial in exactly the level of shock stiffness a particular track requires using the four standard, independently adjustable dampers with Laguna Seca-specific valving."

I look at the rear LCA's on the LS and are different than on a base 302. I haven't seen a post about somebody actually testing the spring rates and doing comparisions.

Also, most in that thread are going to a GT 500 damper. (There were two in your thread that are just using springs but one was using a J&M.)

Do you have the part numbers off your springs?
Has anybody measured the height of the springs?
Also, do the springs require a different strut plate for an LS?

The rear springs out of my LS measure 13 3/8" tall. (However, I have no idea how stiff the spring is.)

I don't care about the look, this is strictly from the stance of leveling out the car, lowering the COG and getting better performance. I don't drive it on the street.

Thanks.
 
Frosty - powertrain is identical so the first statement is not a difference between the LS and regular Boss.

Both cars sit the same distance from the ground. The spring rates are higher and the damping may be slightly different. Rear sway is slightly bigger 1mm) due to extra 1/2" diameter on rear wheels and slight increase in stiffness from X brace. That said the differences between the two cars is minimal in terms of track performance. (We had a good mix of them at the Mustang Roundup last year and wheels &tires had a much more profound impact than the suspension)

When I decided to upgrade my suspension I asked Ford Racing about upgrading to the LS suspension and was told there wasn't enough difference to be worth it. That's why I ultimately went the route I did.
 
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Thanks Cloud for the info.

With that, the P springs sound like they will balance the LS out just like the 302. However, as you confirmed the valving is a little different in the LS. I just want to try the springs first if balance the car and my hope is they are as least as stiff as the LS springs or maybe a little stiffer without purchasing the GT 500 dampers.

I think if I replace the suspension, I'll be going with coil overs down the road.

So the final question is, does anybody know (actually tried) to see if these springs will work with the Boss front strut plates?

Thanks everyone.
 
I'm not sure if they work with the stock Boss strut plates.

There is not that much difference between the suspension on the cars and my understanding is the LS was optimized for the added rigidity AND the R compound tires. Mark Wilson from Ford Racing posted that the P springs will be fine the Boss dampers and there's no reason why they wouldn't with the LS dampers. I don't think the 18000-C dampers come on the GT500 SVT handling package cars but maybe they do. I've read that Shelby installs the entire FR3 adjustable handling package on their GT350. The LCA's are the same on both cars.

http://www.fordracingpartsdirect.com/2005_2012_MUSTANG_GT_ADJUSTABLE_FR3_HANDLING_PACK_p/m-fr3-mgtaa.htm

For comments on the P springs on a LS read roketman's comments towards the end of the thread below.

https://trackmustangsonline.com/boss-302-racing/anyone-interested-in-a-3-day-weekend-event-at-watkins-glen-%28622-624%29/
 
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Today I called H&R to talk to them about spring rates and what I'm trying to do. He dug around and said he found info somewhere that the stock spring rates are. (Not sure if it's 100% correct.)

F - 137lbs
R - 191lbs

He told me the rates on the standard boss but I forgot to write them down. I do remember saying they were a little stiffer up front and softer on the rear.

Also, the rates on their H&R Race springs are:

F - 325lbs
R - 285lbs

I'd be curious if anybody knows the rates of the FR 5300-P springs. If so please post them here for others. The other springs I've heard suggested are the Steeda boss springs but I've seen threads that they may limit the MM camber plate range. (I have not verified.)

I think I'm going to try the H&R's after with the stock suspension.
 
5 DOT 0 said:
Have you read this thread? Everything in there should apply to your car. The P springs will lower your car about 1" in the rear and 1/8" in the front.

https://trackmustangsonline.com/boss-302-technical-forum/ford-racing-suspension-upgrades/

Frosty, the ride height is different on the LS vs the std 302 as is the torsen. If you e-mail off line I will forward the specs. from Ford on the suspension setting.
 
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Thanks Jim,

I'm referring to spring rate versus ride height. H&R claims 1.5 lower in the front and 1.4 in the rear but that's based on a GT and the bosses from what I'm told are lower from the factory.

I'm going to wait until I get these springs and I'll post about the heights. I care nothing about the look, but just trying to get the "optimal" rake as well as making sure the springs I get somewhat stiffer than what I have right now. I don't like the inconsistencie in the braking setting up for slaloms.

PM is on the way because I can use all the info I can get. :)
 

JScheier

Too Hot for the Boss!
SUSPENSION
• MacPherson strut with L-arm front suspension
• 8.8 inch solid rear axle with limited slip differential (3.73:1 ratio)

Boss 302:
• 34.6 x 4.4 mm tubular front stabilizer bar
• 25.0 mm solid rear stabilizer bar
• Tokico twin tube adjustable shocks and struts
• 26.0 N/mm front and 32.4 N/mm rear coil springs

Boss 302 with Laguna Seca package:
• 34.6 x 4.4 mm tubular front stabilizer bar
• 26.0 mm solid rear stabilizer bar
• Tokico twin tube adjustable shocks and struts
• 24.0 N/mm front and 33.5 N/mm rear coil springs
 
KK1826 said:
I am also thinking of doing the same.
Any feed back will be great.

sorry for the error when I was looking at the alingment sheet I was looking at the gt 500. The ride hieght is the same. I can not find the sheet that explains the difference in the two diffs. I think was the bias ratio do to the R tires. Again sorry for the miss info.
 
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I would just go with the P springs. With the MM caster camber plates the springs will work fine without having to do any changes in the strut mount. Just make sure you get the 2011+ plates....

However if you want the very "optimal" setup you need to do a lot more. Since you are lowering the car in the rear you need an adjustable panhard bar to center the rear axle. You will also need rear lower control arm brackets to adjust the angle of the rear lower control arms. You may need an adjustable rear upper control arm to correct the pinion angle. You will want the FR jounce stops because the car is lowered.

To make a long story short get what Cloud9 did and you will be set! It is a proven formula..... The only thing I would do, and did do, differently is I would get the Sam Strano front and rear adjustable sway bars.
 
Quite frankly, I'd actually be interested in stiffer springs - a good deal stiffer - that more or less preserved the stock suspension geometry. If you are building to a specific race class, springs are generally doable, while relocating suspension geometry components can be a deal-breaker.

More, and better, spring options would be nice, is what I am saying. Wonder if Vorshlag would magic me up something...
 
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Thanks Adam but I'm going with the H&R's.

I already have the Spohn Adjustable Pan Hard.

I also have the adjustable sway bars but so far, I can only run the rear in full stiff. In the mid hole, the driver side mount is up against the exhaust. Speaking with Sam, I'm going to try and turn the mount around to see if I can get the rear back in the middle.

I'm pretty sure I can't change the LCA's but if I need to adjust the pinion angle, I'll look at an adjustable UCA.

H&R didn't seem to think the angle would need to be adjustable.

I'll go off the numbers from this video when checking.

http://www.youtube.com/watch?v=i8FNgaNqS8s&feature=player_embedded
 
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Let us know how you like the springs. Again I would go with the Ps.......

You absolutely do not want to be full stiff in the rear..... Unless you have the need/love to drift

You can't adjust the LCAs in stock form. You need LCA brackets. There are a few companies out there who make them but I would get the FR ones. They come with two positions. You need to use the lower position. With the 1.5in drop in the rear from the H&R springs you really need to do this if this is a track only car....

I really think you need to talk to some more people and do some more research. You said this car doesn't get driven on the street at all so I assume it is mostly a track beast. If this is true your planned suspension is way of line........

The suspension aspect of this car has been hashed out, researched, and proven. There is nothing special about the Boss chassis. It is a S197. The stock suspension is a very nice step up from a GT. However you can take a GT and make it handle JUST as good as a Boss for the same money.....besides adding the torsen if you don't have that.

I would do what has been proven....... Good luck!
 
adam81 said:
Let us know how you like the springs. Again I would go with the Ps.......

You absolutely do not want to be full stiff in the rear..... Unless you have the need/love to drift

You can't adjust the LCAs in stock form. You need LCA brackets. There are a few companies out there who make them but I would get the FR ones. They come with two positions. You need to use the lower position. With the 1.5in drop in the rear from the H&R springs you really need to do this if this is a track only car....

I really think you need to talk to some more people and do some more research. You said this car doesn't get driven on the street at all so I assume it is mostly a track beast. If this is true your planned suspension is way of line........

The suspension aspect of this car has been hashed out, researched, and proven. There is nothing special about the Boss chassis. It is a S197. The stock suspension is a very nice step up from a GT. However you can take a GT and make it handle JUST as good as a Boss for the same money.....besides adding the torsen if you don't have that.

I would do what has been proven....... Good luck!

Yes, This!
 
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First, talking to more people at this point is the last thing I need to do, right Bill??? hahaha

You are correct, anybody doing a road course and who wants to change out their shocks/struts along with the springs, definitely the setup from the GT 500 handling pack seems like a very capable upgrade.

Break down of why I'm going with these springs. I have other threads talking about car setup so I'm going to try and not overlap that here.

  • Called Ford Racing and the person strongly suggested not changing to the 5300 P spring. I really think it's because he didn't know me and they haven't tested the springs with the Boss and they are made for the GT 500. If you go to the FRP site, you can see them unt the GT 500 handling pack. To me i sounded like a liability response or a situation they don't want people calling in complaining.
  • I've yet to see the spring rates posted on the 5300's and I wanted to know exact specs. H&R was extremely helpful in answer questions and giving specs.
  • Even with that said, the guys on here are the best and despite the above I would probably give the 5300's a try just based on their feedback and experience which is way greater than mine. However, just about all of them seem to have also went with the GT struts instead of just installing the springs on their stock strucks. There was some question as to whether these springs would work with the stock struts so that was the deciding factor of just going with the H&R Race springs. (That and a couple of people I've talked included them in a short list.)
  • Autocross ESP rules state you can not change LCA's
  • There should not be a 1.5" drop in the rear using the H&R springs. Like the 5300 springs, they were made for a different Mustang model and these were for the GT. That is what the drop rates are based on. According to HP, our Boss sit lower from the factory than the GT's so it's not expected to be anywhere close to a 1.5" drop in the rear. I'll post what it is when I get them.
  • Your comment about a stiffer rear, I think you mean to say you don't want stiffer rear spring in the rear than the front or you'll end up with oversteer. Especially as several have pointed out when you go from the stock staggered setup to a square setup like I have. Stock springs are 191 rear and 134 front which along with the rake, stiffer swaybar lead to oversteer which I'm trying to address. The H&R springs are 325lbs front and 285lbs rear so I am going to a softer overall rear setup
  • I'm a little confused by some of your comment. First you say go with the proven method which changes out quite a bit, but then I think you're saying it's better stock?
  • Torsen is stock on an LS

The only reason I'm changing springs is I don't like the inconsistently in braking setting up for tight sections on an autox course. That's my only complaint with the car right now.

Tires are a big part of it, but so far with everything I've changed, I've hit 1.31 g's at my first event on with my setup. This past weekend I went to an autox at Carolina Motorsports. It's a road course and they setup two "Autox". You pretty much just ran the track with a couple of slaloms thrown in on the long straights.

My gauge showed 1.26 g's (And no I'm not jerking the car trying to get high score on the gauge. haha.)

Results for what I have setup right now.

First time ever seeing a Road Course, 4th autocross, second on my new setup, on the slower of the two tracks, I missed overall fastest out 89 cars by .11 seconds with a 56.08. (However, I clipped a cone with my rear wheel at the end of the run.) I suck at the slaloms right now.

On the faster track I was 4th fastest out of 90 cars that ran the entire day.

http://www.rjtiming.com/results/East.pdf

Here's a break down by class.
http://www.rjtiming.com/results/EastClass.pdf

I should add, I had to change the sway bar's from the middle hole to full stiff because the rear mount was up against the exhaust. I didn't like the change and had to get used to it throughout the day. (When I get the new springs on, I'll be trying to figure out a way to go back to middle settings front and back.)

FYI. I'm not running the car stock because to a person, every person I called or got a response from said 18" wheels were the only way to go.

Then if I changed to them apparently that has led to all the other things. So I would agree, if running in a class that required the 19" wheels, then the stock boss setup seems it would be hard to beat.

Personally, if I had to run 19's I doubt I would have done anything but change tires. (Which by the way was the only thing I was going to do when all this started. That was before talking to more people and do more research. ;D)

If I grew past that, then I'd probably go to a coilover and have the car weight balanced.

However, if you are not constrained to the 18" wheels, then what I have so far I'm extremely happy with. I'm hoping these springs take braking problem.

I hope this helps others. Again, I have a Setup for Autocross thread where I got a lot of good advice which was a tremendous help.
 
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Additionallly, I see these threads all over the internet advising people to just drive what you have and then change in increments. I'll offer a different opinion here. I'll preface as I usually do, I'm just beginning competition on 4-wheels. My previous racing was on 2 wheels. (MX)

(And it's ONLY an opinion. In the end the only opinion that matters is the one that makes the person happy spending the money and driving the car.)

From experience I don't care for that advice. I'm strictly speaking from the standpoint of if you want to be competitive in the fastest time possible. Getting fast mostly comes down to seat time and experience. My philosophy is get the car setup for the class you can afford to run in and then learn to drive it.

Driving this car as was for Auto-x was like driving on ice. I had to run in ESP class and 5 secs slower than cars on tires and coil overs. This is on 60 second courses.

My first thought was to just get on the same tires as the fast guys. But that would have led me to purchase 19" tires staggered like stock. Then I would have figured out I should have went to 18" wheels and 295 all the way around which would have led to purchasing a 4th set of tires.

Then I would have learned pretty much how to drift around the courses to try and compete because all of the oversteer. Drifting & trying to go fast in autox don't mix.

Changing down to the 18's, with a stock setup, I would have had to learn a different feel and probably deal with more oversteer if I did nothing else.

Then you figure out that Hoosier tells you if you run their tire you optimally should run a -3 degree camber so you make that change and it's another adjustment period. If you don't, unless you figure out some way to round the edges, there may be a good change you cord the edges. That's not a cheap lesson to learn either.

Also, keep in mind you're lucky to race 2 times a month. Then if you get to spend more than 4 minutes on track during an event, your lucky.

Hopefully everybody can see where I'm going with this. You only have so much seat time and I don't think many will argue, getting seat time and the feel of the car is about the only way to push it to it's optimal limit. Starting out and doing changes here and there is constantly changing the characteristics which to me extends your learning curve and usually ends up costing me a lot more in the long run.

The caveat to this, if you're new to something then go do it a couple of times without spending money just to make sure it's fun. I do agree with the advice of not going out and spending a bunch of money until you are sure competition is for you.

Also, again, think about a budget for yourself and then try to find a class that matches that budget. Maybe you just want to run the stock class but to compete in STock, you still have to purchase tires to have a chance. Again, I had no choice but to run ESP and is the reason for what I'm doing.
 
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