MM road and track springs VS h&r race springs

[Sjohnson1800]

I’m looking into getting new springs and camber plates I think I’ll go with the mm camber plates. But I’m not sure on what springs to get I have KONI yellows already. I’ve tried searching for info and on the road and track springs but not much comes up the H&R’s seems to have a good spring rate and don’t lower to much and have had good reviews. I don’t drive the car to much only on weekends and not really to far. The only boy downside to road and track springs to me seems to be how low they are but was hoping for some info from you guys

thanks
Steve

 

[AdmirC]

I have a suspicion that they are actually the same spring. I have no proof but they have the exact same windings and layout. Also, their advertised rate is roughly the same. Drops are not an exact figure so the .5 inch difference in them may just be a marketing thing. I have the H&R race springs and their a good dual purpose spring. They can be a bit harsh on rough roads. This is how my car sits on the H&Rs.

 

[Sjohnson1800]

Yeah maybe I’ll just go with the h&rs it seems like they get pretty good reviews and your car doesn’t look to low at all thanks!

 

[Fat Boss]

I had the H&R race springs on my 2nd Boss and they were pretty miserable on the street. They were great on the track. The P springs were a much better compromise for me since most of my driving was on the street.

 

[blacksheep-1]

buy a Ford Performance kit and be done with it, all the parts work together and all the engineering is already done as well.

AmericanMuscle

www.americanmuscle.com

 

[s9669s]

AdmirC, I am trying to get a feel for how ride height of these would compare to the BMR handling springs I am running. Can you measure the distance from the fender lip to the wheel center front and rear? (Lip to wheel center to remove tire OD as a variable.)

 

[AdmirC]

AdmirC, I am trying to get a feel for how ride height of these would compare to the BMR handling springs I am running. Can you measure the distance from the fender lip to the wheel center front and rear? (Lip to wheel center to remove tire OD as a variable.)

Yeah I will once I get the car on the ground, currently doing a couple things to it but shouldn't take too long.

 

[AdmirC]

AdmirC, I am trying to get a feel for how ride height of these would compare to the BMR handling springs I am running. Can you measure the distance from the fender lip to the wheel center front and rear? (Lip to wheel center to remove tire OD as a variable.)

The front is 14 1/8 and the rear is at 15 inches. The vehicle has about an 1/8 of a tank of fuel in it due to having the fuel pump out so the rear is up, I think it settles to about 14.5 inches with a full tank.

 

[s9669s]

My car sits at about 14-1/8" F / 15-1/8" R on the Mustang GT BMR handling springs. I was hoping the H&R springs were a little taller in front. Looking to go stiffer next year...likely either H&R Race or GC sleeves.

Steve, if you want a spring with reasonable on-road comfort and a good stance, the BMR Handling springs (or Ford Performance) are a good compromise, but if you are going to get serious about autox or track work, you may find them a bit too soft as I have.

 

[Sjohnson1800]

Yea I have the FRPP k springs and I don’t think the springs rates for the bmr are that much stiffer that’s why I was looking at the h&r race springs

 

[302 Hi Pro]

S. Johnson:

I’ve followed along here and find it an interesting thread as it reminds me of my 2012 Boss 302 quest to replace the OEM Boss springs. Back in the day, I had read that Ford Racing was in development of a Boss 302 specific lowering spring kit & it took FR about 8-12 months for them to release this spring kit, so I had a lot of time to study the pros & cons of lowering my Boss while waiting for FR’s Boss spring kit specs.

Before you make your final decision, consider the total, (settled spring) drop on your front suspension geometry. Especially the steering geometry, (as you lower the car you lower the rack&pinion mount juxtaposed to the unchanged position of the tie rod ends. (Note: You’ll also need to consider rear suspension upgrades when lowering.). Remember it’s a balance between front & rear suspension setups.

IIRC The FR Boss 302 specific lowering spring kit (M-5300-T) only lowered the OEM Boss front height by

• Lowers car approximately 15mm (0.6-inch) front and 35mm (1.375-inch) rear

If you exceed 15mm front, you should consider other front end parts replacement to keep a compliant front end suspension geometry. Good luck with your quest.

ps: H&R springs are excellent quality German made springs, just keep an eye on the total drop.

 

[V8VOL]

I am having the same dilemma as the OP. Do I go with H&R race springs or MM R&T.....Currently on 05-09 Sportline springs on my 2014. I want a higher spring rate, but need to be careful about going any lower on the front. I am running 19x11's with 305 tires and its VERY close to a rubbing situation.

 

[Norm Peterson]

As another data point, I'm running Koni yellows with BMR's GT500-spec handling springs (260/220). The drop on the lighter non-GT500 car was about 0.5" up front and about 1.1" out back. The rear can be shimmed to better equalize the amounts of lowering and for rear suspension geometry reasons. I'd started with about half an inch of shim (~5/8" lowering) but have taken another 3/8" out of the lowering as part of a separate mod (that's not yet finished ).

It is my opinion that the value of lowering tends to be over-rated, particularly when MacStruts are involved. Some of the added rate gets 'wasted' compensating for the CG height to geometric roll center moment arm increasing, and while grip at the outside tires benefits from having less load transferred onto them, transferring less load off of the inside tires reduces their cornering effectiveness slightly. Forward bite at the rear tires on corner exit may or may not improve.


Norm

 

[302 Hi Pro]

Koni Sports (yellow) initial settings that work well on my 12 Boss 302 are 85% stiff front & 60% stiff rear. This give me room to fine tune. (Note: while the Koni Sports are a big improvement over the OEM Boss springs, there really not much difference in making 1/4 or 1/2 turn adjustments)

Insofar as springs? First was Ford T springs front/rear, but the car needed more clearance in the rear so I experimented. I did the unthinkable, as I installed a set of rear Steeda Boss springs. With my particular setup the results were amazing on corner exit.

 

[Norm Peterson]

Koni Sports (yellow) initial settings that work well on my 12 Boss 302 are 85% stiff front & 60% stiff rear. This give me room to fine tune. (Note: while the Koni Sports are a big improvement over the OEM Boss springs, there really not much difference in making 1/4 or 1/2 turn adjustments)

I think Koni yellows for the S197 stiffen up by about 5% - 10% per quarter turn. But it is not a uniform, fixed increase sort of progression.

Insofar as springs? First was Ford T springs front/rear, but the car needed more clearance in the rear so I experimented. I did the unthinkable, as I installed a set of rear Steeda Boss springs. With my particular setup the results were amazing on corner exit.

I was running a bit less adjustment with OE GT springs (pretty soft, down around 130 - 140 IIRC), and a bit more with the 260/220 BMR springs. +1.5 turns still didn't feel quite enough for the rears.


Norm

 

[AdmirC]

I think Koni yellows for the S197 stiffen up by about 5% - 10% per quarter turn. But it is not a uniform progression.


I was running a bit less adjustment with OE GT springs (pretty soft, down around 130 - 140 IIRC), and a bit more with the 260/220 BMR springs. +1.5 turns still didn't feel quite enough for the rears.


Norm

I find that if I run anymore than 3/4 turn in the rear from full soft that the rear end seems to skip over bumps and has way too much rebound. Also it has trouble on power exit with bumps with anything stiffer. It is a bumpy track though.

 

[Grant 302]

I think Koni yellows for the S197 stiffen up by about 5% - 10% per quarter turn. But it is not a uniform, fixed increase sort of progression.


I was running a bit less adjustment with OE GT springs (pretty soft, down around 130 - 140 IIRC), and a bit more with the 260/220 BMR springs. +1.5 turns still didn't feel quite enough for the rears.


Norm

@Norm Peterson - What settings did you use for the GT springs? How much higher did you go with the BMR upgrade?

 

[Norm Peterson]

Pretty sure I ended up running 6 quarter turns up from full soft up front and 5 quarter turns up from full soft out back with springs that were 136f/142r or close to that. Some of that was probably to crutch the springs being that soft, but it seemed to work pretty well.

I think I ran one session with the BMR springs at +8f / +7r quarter turns and it still didn't feel like quite enough.


Norm

 

[Grant 302]

Pretty sure I ended up running 6 quarter turns up from full soft up front and 5 quarter turns up from full soft out back with springs that were 136f/142r or close to that. Some of that was probably to crutch the springs being that soft, but it seemed to work pretty well.

I think I ran one session with the BMR springs at +8f / +7r quarter turns and it still didn't feel like quite enough.


Norm

Thanks. I understand about using whatever damping available for ‘feel’ and/or personal preference. I wanted to hear your take on usable settings.

Apparently, if I ask you more than that publicly, I would be confirming my argumentative nature...but it’s more about curiosity and trusting what I consider to be a good source for accurate and reliable information. Thanks again.

 

[302 Hi Pro]

I find that if I run anymore than 3/4 turn in the rear from full soft that the rear end seems to skip over bumps and has way too much rebound. Also it has trouble on power exit with bumps with anything stiffer. It is a bumpy track though.

I have to agree with you, and I’ve done the same from my ‘initial’ 80/60 ish setting starting point.