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Looking for spring reviews and recommendations? K vs P vs T?

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Thanks for the info. Better than FR3 because of the springs, and/or struts? I spoke with MM the other day, asked about the springs among others things. Told me their kit uses H&R springs, said they are specially made for MM. Maybe the H&R race springs? Drop is minimal for the Boss; 0.04" rear and 0.4" front. Not sure I would need the entire kit as some Boss components might be reusable like the FSB. Did you install the RBT-51 kit on a Boss? Are you running a square setup? LCA relocation brackets?
Both, the springs and the struts are better IMO. I ran square with that set up. The drop was 1.5-2.0" the drop on the Boss will be about the same. I don't run the LCA relocation brackets ATM but did with the spring set up.. Have had to use them on other cars as well. Start without them and then if you need more rear grip add them. I lot of race teams never even ran them.
My fast lap so far at Button Willow was with :
Koni yellow Sports
MM R&T springs
Ford Racing Pan hard bar
Ford Racing LCA relocation Brackets
Ford Racing boss 302R LCA
Eibach 36mm Front sway bar
18mm rear sway bar.
It pulled a 2.02 with old 275-35-18 Conti race slicks, was easy to drive and I drove it on the street every day.
 

Norm Peterson

Corner Barstool Sitter
939
712
Exp. Type
HPDE
Exp. Level
5-10 Years
a few miles east of Philly
FAST!!! Trying to determine if the MM track & grip box or the FRPP FR3 handing pack is a significant improvement over the Boss stock suspension. Or if a minor mod (springs) is enough. If the MM T&G or FR3 is only a small improvement, I'll need to adjust my thinking towards coilovers. This thread suggests that the FR3 pack is very similar to the Boss 302S suspension. Good enough for the 302S is good enough for me.
How fast is FAST? What sort of lateral g's? R-compound or better tires?

The reason I ask is because the amount of grip you gain from lowering isn't as simple as looking only at the improved situation on the outboard tires. Long story short, while you're gaining a little mu from having less load transferred onto the outboard tires, you're losing some mu by having less load transferred off the inboard tires. Overall, it is a gain, but smaller than the reduction in load transfer.

I have a few datalog plots for my lightly modified and unlowered at the time '08 GT. Here's one from NJMP/Thunderbolt. 285/35-18 MPSS tires on 18x11's. I've since lowered the suspension, all of something like 0.6". There's another 0.6"-ish amount of lowering courtesy of the 25.9" tall tires.

picture.jpg


Norm
 
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Norm Peterson

Corner Barstool Sitter
939
712
Exp. Type
HPDE
Exp. Level
5-10 Years
a few miles east of Philly
Thought I'd mention that the lower springs in there now are BMR's 'Handling Springs' for the '07 - '09 GT500, the kit I was able to get being slightly stiffer than the 'Handling Springs' for a 'regular' GT and lowering somewhat less especially up front.


Norm
 
The Boss stock setup is 0.98g, lateral acceleration. The MM T&G kit ups it to 1.2g at a cost of ~$1900. Coilovers run $3k to $5k, but not sure of the performance gains in terms of lateral acceleration. I plan to start running NT01 305s square on 18x11 wheels, or maybe 295s.
 

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