Radiater

I am considering doing about a 1 grand worth of mods to my 11 GT Brembo.

Shocks/struts/springs/swaybar,etc as is typically recommended here and some other sites.

I admit I am a complete novice and I respectfully ask....do you guys have objective data or skid pad data showing these mods work and how much?

Sam Strano

How well it works depends on how good a setup you go with. Here's a little data for you... my '11 GT autocrosses are fast as a '10 Corvette Grand Sport (both on the same tires, both with tweaked alignments for autocross). Considering the C6 GS has a lot less weight, is smaller, has more power and a way better stock suspension, I think that's pretty telling.

BTW, those results are with me in both cars, having won multiple National events this year in both.

Skidpad numbers aren't truly that relevant in the real world. There are no dynamic transitions, and I can't find any place to just drive in 200' circles. And tires alone make a massive difference on a skidpad. Handling is a lot of things combined. How the car drives, how easy is it to drive, or nervous? What is the balance like? How does it work on bumps? Are the mods you are making useful for you everyday? How is the response? how well does the car take a set, etc. etc.

Radiater

Thank you Sam. That is a useful comparison because I know the GS is a pretty decent car stock and for a Mustang to handle like one is pretty impressive.

I posted this because I hear so many people talk about all their suspension mods but don't seem to see any objective data posted. It would be nice if people took the factory car to the track and listed the lap times then made mods and posted lap times.

Griggs and Agent 47 systems appear to be much more wholesale changes in suspension and cost much more. Sort of hard where to know where to start and stop and where the diminishing returns are for the average user.

Sam Strano

I can tell you that the last time I did an A/B test was on a 2001 Z28. My springs, bars, and Koni's caused the car to go 3.4 seconds a lap quicker on a short, slow road course in New Jersey. With the addition of better tires, he went another 3.5 quicker (and the suspension handled it, as it should since I set it up around good tires). That's a total of 6.9 seconds a lap faster.... Of course, this is also a solid axle pony-car.

As for A/B testing, it's hard for me to do since autocross courses are always different, what I can do it run against the same folks, of known performance in cars that are not being tweaked on setup, and see how it goes. And of course, there is the matter of simply having folks find the car much more happy on the road too.

Sam Strano

I should also add that the C6 I was comparing is all setup to autox in Super Stock. And I also have a C6 of my own... And those cars aren't stock either. Both have shocks that are $1300 a set (Koni's, and way, WAY better than stock GM shocks). And both cars have custom front sway bars too.

DPE

I wouldn't place too much emphasis on objective numbers when it comes to 'handling'. Of course you want the numbers to improve, but sometimes things that will only give you a nominal improvement in a test number give you a massive improvement in how the car feels. If the car feels better and responds more directly and consistently, that gives the driver more confidence in the car. A driver with more confidence can drive faster more comfortably, which is ultimately more fun.

Case in point. My car has GT500 wheels with 275/40 summer tires, Koni Sport shocks, and Steeda upper mounts. The Steeda mounts gave me a bit more negative camber which reduced understeer a bit, but otherwise the big improvement in terms of improving objective handling numbers came from big, sticky tires. The shocks probably did very little to improve overall grip. But holy hell do they make a difference! Much less body roll/squat/dive. Turn-in is nearly instant rather than ponderous. Even the lamented rear axle stays in much better control over mid-corner bumps. And the whole chassis just communicates better, making it much more confidence-inspiring in the corners. Worth every penny.

Anyway, just my 2 cents. If you've got a grand to spend and already have good summer rubber (which you do, I think, if you have a Brembo car), I'd personally start with a set of Koni Sports and possibly springs and work from there. I didn't do springs because I wanted to see the effect of just the shocks and because it's a PITA where I live and drive to have a lowered car, but many seem quite happy with them. I'm certainly happy with the shocks by themselves.

And Sam, I've got three new roundabouts less than a mile from my house, so if you would like a place to drive in ~ 200ft circles I can provide one . I've certainly taken advantage a time or two...

JAJ

Another interesting comparison is my 2011 GT Brembo and my 2008 BMW M3 (V8). Both cars weigh the same, have the same wheelbase, the same track width and the same horsepower. The BMW has an independent rear suspension and the Mustang has the stick axle.

I do a lot of track days, and to help me understand how I'm doing in a track environment where timing is disallowed by insurance rules, I've built myself a data logging gizmo that allows me to see how much of the vehicle's traction circle I'm using without giving away my lap times. To get a clear picture of the vehicle's performance, I can look at individual laps or at an entire day of running compressed into a single picture.

So far, the data analysis shows that the Mustang with Sam's recommended setup of Koni Yellow's, Steeda Sport springs and a Fays2 Watts link used with Nitto NT01 r-comps gives essentially identical cornering (lateral G's) and handling to the BMW M3 with a KW Clubsport suspension and the same NT01's (literally the same NT01's). The 5.0's higher torque actually gets it off the corners better than the M3. On those occasions where lap timing is allowed, my 2011 laptimes in the Mustang are essentially the same as last year's BMW M3 lap times.

Radiater

DPE, JAJ, and Sam...thank you for sharing your experiences with suspension mods. I feel like I have a better understanding of how they affect the performance of the car.

scottybaccus

For the low tech opinion, I'll say that lowering springs with increased rate did amazing things for my stock V6. It's still mushy by comparison to what Sam plays with, but it's light years ahead of OE.

eolson

I remember driving my stock 06 GT coupe on a very twisty road going up and down a canyon in Griffith Park LA that was deserted in the early morning on Sat and Sun, and timing myself on the run, many, many times.

Just getting the Saleen suspension(springs, shocks/struts and both swaybars) made a difference in the time it took me to do the 2 minute run. Seemed to take off 5 or 6 seconds or so off the time I was getting before as I recall.

Obviously the Steeda springs, Koni Shocks and Strano adjustable sways would be even better than my original Saleen set up, but i must say for the money at the time, it was the biggest improvement by far of anything suspension wise.

Later, adding to that the Techco Watts link also made a huge difference in ending lateral travel over bumps while in harder curves, grounding the tire grip and preventing kick out, boosting my confidence. I would put the Watts link up there with the other basic suspension improvements that I felt right away as a big plus canyon driving. Erik