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Lowering springs

ihatepotholess said:
i too find it weird why is the back end wiggling under hard braking in a straight line. i have never experience this in any other cars before. i will try 5 in the rear and keep 4 in the front.

i know some of you guys have a lot more track experience than i do, and you are probably used to the back end jumping around. but i like my cars a little more predictable, hopefully the FRP springs will solve this problem.

I think your going the wrong way. Ideally you need to increase front compression and reduce rear rebound. Since our shocks don't adjust compression and rebound separately, I would try setting the front to 5 and the rear to 3 and see if that helps.
 
BossJockey said:
ihatepotholess said:
i too find it weird why is the back end wiggling under hard braking in a straight line. i have never experience this in any other cars before. i will try 5 in the rear and keep 4 in the front.

i know some of you guys have a lot more track experience than i do, and you are probably used to the back end jumping around. but i like my cars a little more predictable, hopefully the FRP springs will solve this problem.

I think your going the wrong way. Ideally you need to increase front compression and reduce rear rebound. Since our shocks don't adjust compression and rebound separately, I would try setting the front to 5 and the rear to 3 and see if that helps.
I would agree. Of course I run 5 all the way around.
 

OLOABoss

AKA OLOABoss
BossJockey said:
ihatepotholess said:
i too find it weird why is the back end wiggling under hard braking in a straight line. i have never experience this in any other cars before. i will try 5 in the rear and keep 4 in the front.

i know some of you guys have a lot more track experience than i do, and you are probably used to the back end jumping around. but i like my cars a little more predictable, hopefully the FRP springs will solve this problem.

I think your going the wrong way. Ideally you need to increase front compression and reduce rear rebound. Since our shocks don't adjust compression and rebound separately, I would try setting the front to 5 and the rear to 3 and see if that helps.

If the back end is not staying planted during braking you want to slow the transfer of weight forward which would mean more rebound in the rear and more compression/stiffer springs in the front.

Peter
 
Peter, are you still using the Steeda Boss springs? How do you setup your car for the track? Are you having any issues with the rear getting light under high speed braking?
 

PeteInCT

#LS-378 - So many Porsche's, so little time....
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OLOABoss said:
BossJockey said:
ihatepotholess said:
i too find it weird why is the back end wiggling under hard braking in a straight line. i have never experience this in any other cars before. i will try 5 in the rear and keep 4 in the front.

i know some of you guys have a lot more track experience than i do, and you are probably used to the back end jumping around. but i like my cars a little more predictable, hopefully the FRP springs will solve this problem.

I think your going the wrong way. Ideally you need to increase front compression and reduce rear rebound. Since our shocks don't adjust compression and rebound separately, I would try setting the front to 5 and the rear to 3 and see if that helps.

If the back end is not staying planted during braking you want to slow the transfer of weight forward which would mean more rebound in the rear and more compression/stiffer springs in the front.

Peter

+1 !
 
OLOABoss said:
BossJockey said:
ihatepotholess said:
i too find it weird why is the back end wiggling under hard braking in a straight line. i have never experience this in any other cars before. i will try 5 in the rear and keep 4 in the front.

I think your going the wrong way. Ideally you need to increase front compression and reduce rear rebound. Since our shocks don't adjust compression and rebound separately, I would try setting the front to 5 and the rear to 3 and see if that helps.

If the back end is not staying planted during braking you want to slow the transfer of weight forward which would mean more rebound in the rear and more compression/stiffer springs in the front.

Peter

What your saying makes since. I was going by the FR500S setup guide.

[pdf]http://www.fordracingparts.com/Mustang/fr500sownerinfo/Sachs_Damper_Guide_FR500S_v1.pdf[/pdf]
 

OLOABoss

AKA OLOABoss
5 DOT 0 said:
Peter, are you still using the Steeda Boss springs? How do you setup your car for the track? Are you having any issues with the rear getting light under high speed braking?

Yes, still on the Steeda's and the rear does not walk under braking. Going to Sebring Sunday with the new One Lap tire setup. Michelin PSS 265/35 19 front and 295/30 19 rear on 19x9 19x10 F14's. Got Ian Stewart along to wring it out and work on tire temps/pressures and give me some coaching. This will be the test to see if it is as fast as my stock 6GT3 which runs 2:27.5 on AD08 street tires at Sebring.

Peter
 
OLOABoss said:
Yes, still on the Steeda's and the rear does not walk under braking. Going to Sebring Sunday with the new One Lap tire setup. Michelin PSS 265/35 19 front and 295/30 19 rear on 19x9 19x10 F14's. Got Ian Stewart along to wring it out and work on tire temps/pressures and give me some coaching. This will be the test to see if it is as fast as my stock 6GT3 which runs 2:27.5 on AD08 street tires at Sebring.

Peter
Thanks. Do you have the stock rear spoiler on your Boss?

Everything I've read leads me to the AD08's and PSS as potentially the best street tires for track use for our cars. Any feedback you can provide on their on track performance is appreciated.

Have fun with Ian Stewart and pass along any tips he has that apply to our cars.
 

OLOABoss

AKA OLOABoss
Yep stock rear spoiler. If I go for more aero it's going to be a real wing up at the roof line. I really like the AD08 so it will be interesting how the PSS compare. I do know the PSS is a much better wet tire with much less under steer than the AD08 from testing at CMP in the wet.

Peter

5 DOT 0 said:
OLOABoss said:
Yes, still on the Steeda's and the rear does not walk under braking. Going to Sebring Sunday with the new One Lap tire setup. Michelin PSS 265/35 19 front and 295/30 19 rear on 19x9 19x10 F14's. Got Ian Stewart along to wring it out and work on tire temps/pressures and give me some coaching. This will be the test to see if it is as fast as my stock 6GT3 which runs 2:27.5 on AD08 street tires at Sebring.

Peter
Thanks. Do you have the stock rear spoiler on your Boss?

Everything I've read leads me to the AD08's and PSS as potentially the best street tires for track use for our cars. Any feedback you can provide on their on track performance is appreciated.

Have fun with Ian Stewart and pass along any tips he has that apply to our cars.
 

OLOABoss

AKA OLOABoss
Not going to wing or splitter anytime soon. If I was yes I would do both. I also think the car sits way to high for the splitter to work well but lowering opens up a big can of worms with front bump steer and rear solid axel alignment.

Peter
 
335
1
And you read between the lines..... ;) I do think that the splitter and LS wing would serve you well. At stock ride height the splitter really does need to come down about 1 inch. However I know from experience that it does work. I was playing with the angle at VIR and could tell a difference at high speeds. What I felt was the rear loosen up a bit when I really cranked the lip down. I think it was because the front had more grip, not that the rear was excessively loose...
 
335
1
Oh man, I wish I could make it! I have work stuff that weekend..... Otherwise I would be there in a heartbeat. John's track days are some of the best I have ever done. PLENTY of track time! I recommend it to anyone. Price is cheap and you will literally be exhausted at the end of the day. A lot of people don't even go out the last session....

1:21.6 is your goal...... ;D
 
I found pictures of a Kona Blue Boss 302 with H&R lowering springs. The drop is PERFECT. Does anyone know what kind of H&R springs this person used?

http://forums.thevfmc.org/showthread.php?t=8448
 

Boss3o2

Nice2BEtheBOSS said:
I found pictures of a Kona Blue Boss 302 with H&R lowering springs. The drop is PERFECT. Does anyone know what kind of H&R springs this person used?

http://forums.thevfmc.org/showthread.php?t=8448

The drop is perfect. However, keep in mind, these springs will affect the handling the Boss 302, vs. Stock. The spring rates are un-reasonably soft, and with the stock Boss 302 shocks, the car is very bouncy. A good friend of mine who owns a 12 PW Boss, thought this would be a cheap route to get rid of the fender gap. After a week of driving, he had them removed. His PW Boss 302 will probably never see the track, but in his words, it really took some of the character away from the Boss.

Anyone looking to lower, I would recommend F.R.'s Boss 302S Lowering Springs. 1.5" Fr, and 1.8" Rr
 
Boss3o2 said:
Anyone looking to lower, I would recommend F.R.'s Boss 302S Lowering Springs. 1.5" Fr, and 1.8" Rr

Can you point me in the right direction? I've been searching the FR catalog for 25 min and can't find these. I have found the GT and SVT springs but not anything specific to the 302s other than full kits.

Thanks and in advance I appreciate you taking the time!
 
Boss3o2 said:
Nice2BEtheBOSS said:
I found pictures of a Kona Blue Boss 302 with H&R lowering springs. The drop is PERFECT. Does anyone know what kind of H&R springs this person used?

http://forums.thevfmc.org/showthread.php?t=8448

The drop is perfect. However, keep in mind, these springs will affect the handling the Boss 302, vs. Stock. The spring rates are un-reasonably soft, and with the stock Boss 302 shocks, the car is very bouncy. A good friend of mine who owns a 12 PW Boss, thought this would be a cheap route to get rid of the fender gap. After a week of driving, he had them removed. His PW Boss 302 will probably never see the track, but in his words, it really took some of the character away from the Boss.

Anyone looking to lower, I would recommend F.R.'s Boss 302S Lowering Springs. 1.5" Fr, and 1.8" Rr
That's the problem, just throwing some lowering springs on the Boss, even if they are FRPP, without having them track tested on our cars is risky. Our cars are dialed in very well stock and I don't want to mess with that. If you're just looking to lower your car with no regard to on track performance then buy Steeda Sport springs and be done with it. If you want it slammed get Eibach Sportline's.

Although I haven't received an update I'm still waiting for Ford Racing to come out with their Boss specific springs that will be thoroughly track tested before I make a spring change.
 

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