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OEM+ Boss 302

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Hi All,

I recently purchased a 13' Boss 302 in PW. I am planning to enjoy the car on the streets as well as do a number of auto-x and occasional track day. I am looking to do some basic mods to make the car perform better on the track and at auto-x events without ruining the ride and streetability (no aftermarket springs or dampers... yet), thus OEM+.

So far, I have installed a set of GT500 mufflers (I had to, this is my first V8 car), a Blowfish Racing V3 shifter brace and MM camber plates (max negative camber, zeo toe and lots of caster). Future plans include some 18x11 wheels with performance tires. When I cook the OEM pads and rotors I may look to the S550 upgrade (fluid has already been done).

As this is my first car with a solid rear axle I am looking for some advice from the forum on how to most effectively firm up the rear end. Coming from cars with IRS the solid rear axle is not exactly confidence inspiring. It seems to have a mind of its own and floats around. What is the best way to remedy this without ruining the car?

Thanks in advance!
 
167
218
Exp. Type
HPDE
Exp. Level
3-5 Years
Irvine, CA
Better trailing arms (AKA rear lower control arms) will definitely help.
Since you want to retain some comfort I'd recommend the Boss 302R M-5649-R1 vs anything with spherical or rod ends.
I don't have any experience with upgrading the UCA but I'm not sure that's necessary anyway until you lower the rear.
If you want to spend the money for a Watt's link that will certainly give you more confidence and keep the rear end more planted, but it won't necessarily make you faster unless confidence is your limiting factor. Still worth it for most people short of pure racers.
You could also consider a torque arm but I do not have much knowledge there.
Fortunately, most on this forum know way more than I do and I'm sure they'll chime in.
 
A watts link won't make you faster but it will make the car behave more consistently and I liked the feel when I installed one on my Boss. I'm not a fan of the torque arm unless you have a SC with big power and need help putting the power to the ground. The rest of your mods look solid. Have fun with your Boss.
 

Grant 302

basic and well known psychic
If you want to spend the money for a Watt's link that will certainly give you more confidence and keep the rear end more planted, but it won't necessarily make you faster unless confidence is your limiting factor.

^This. It's probably the easiest path.

...Or commit to learn how the panhard bar behaves. Various parts can be replaced or upgraded to eliminate or reduce the movements that bother you most.
 

Norm Peterson

Corner Barstool Sitter
939
712
Exp. Type
HPDE
Exp. Level
5-10 Years
a few miles east of Philly
Dampers play a big part in handling "composure". So I'm putting adjustable shocks and struts as item #1. Adjustable so you can make firm-ish settings for track and autocross and softer settings for your street time. Maybe even a third set that's softer yet if from time to time you have a passenger who prefers ride quality that's still softer than what you might prefer.

There is a really cheap way of firming up the bushings in the OE PHB.

If your car has the 14" SVT/GT500 brakes, just pads and fluid should be enough for a while.

There are a few spherical-joint rear control arms that are not metal on metal. UMI's Roto-joint arms, for one. Currie at least used to make Mustang arms with Johnny-joints.


Norm
 
We run HR race springs, Koni Yellows and Shelby watts link on “The biznitch” as we affectionately refer to her.

Car works great. Very balanced. Usually 2.5 Camber.



Ca
 

Norm Peterson

Corner Barstool Sitter
939
712
Exp. Type
HPDE
Exp. Level
5-10 Years
a few miles east of Philly
We run HR race springs, Koni Yellows and Shelby watts link on “The biznitch” as we affectionately refer to her.

Car works great. Very balanced. Usually 2.5 Camber.



Ca
Interesting, as I was under the impression that 300-ish spring rates might be a bit more than what yellows could control. Around where are yours set?


Norm
 
Interesting, as I was under the impression that 300-ish spring rates might be a bit more than what yellows could control. Around where are yours set?


Norm
Norm:
KYs are set at max rebound damping I believe. My son set it up. I just drive’m.

But yeah, I think we at the outer edge with the HR for the KYs but the car works great
 
6,363
8,191
Better trailing arms (AKA rear lower control arms) will definitely help.
.

Yes!! people do listen!!!

Compared to the rest, I'm Mr "stock parts are great" . The Boss 302 is an extremely capable platform, as is. I would maybe swap some stuff over from the LS version, and Ford Performance makes some great stuff it all has Ford part numbers on it. I think the target of the Boss was the BMW M3..as I recall.
What's the baseline again?
Ford "blue bar" up front
18 mm bar in the rear
600 up front
350 in the rear..that's with coil overs
so I'd just run Ford Performance springs and their adjustable shocks.
Camber plates and call it a day.
If you track it a real trans and diff cooler
 

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