A square set up on this car without other adjustment leads to oversteer. You can feel it.

 

Sure, what ever you say.

Dave

 

Can you teach my wife that?

 

Agreed. I'm pretty sure "cloud9" has as much track time as anyone on this forum, so I'd consider that more data than you've provided to back up your case...

 

I'm gonna run a 275/40/18 square setup for the first track event, we'll see how I like it. Maybe I won't need to trail brake as much.

If the car is prone to snap oversteer, a Strano adjustable rear swaybar will be installed. Square setup is very beneficial for tire rotation and life.

 

Just to add that the car will take a square set-up but I personally found I didn't like it and started thinking of alternate tires and camber offset and all sorts of things from my racing days when I realized I just want this car for the occasion track day outing as it replaced my Bimmer as a daily driver. If I was hardcore (again) I'd go square for cost, change rims for choice, play with tyres and with camber and look at all kinds of suspension tweaks. And then I'd wonder why I didn't buy a Lotus or Porsche or... I'll happily keep my Boss the way it is.

 

This is kind of my tipping point with my NASA TT build. I have more money than I do points, so I don't know if I'm too keen on spending points on suspension mods that I don't really need to. Replacing sways/panhards, springs, etc. all cost points. I like saving tires as well, but I don't think it's a good idea to spend points to save money. Again, money I have, points I can't do much about.

Having said that - I would be giving square setups a go and seeing what needed to be done to make them work if I wasn't so points-constrained, or were racing somewhere else. It is a money-saving move, no question there. Certainly will not be "better" in terms of lap times, but it will save you money if you are a frequent track fiend. If you only go a couple times a year, perhaps, well - I cannot see why you'd pursue this, there's no point in it. If that is you, just enjoy the car and leave the suspension alone :-)

 

Fenderaddict2 and Lateapex nailed it and someone with Drew's experience and resourcefulness can make it work by making appropriate adjustments. I manage tire life by having two sets of track wheels and swap sides to even out wear. My fronts get replaced more often but with two sets it works. I flip the rears on the rims after a couple days since you can't get any camber.

 

SoCalBoss I am far from an expert here but I tell you what I did.

I wanted to save the factory tires for the street and run 18's on the track. I could not find the NT05's in stock anywhere (295) and had a couple of track days coming up so I ordered a set of 18x9 18x10 rims with the 555's on them. The height was great. I ran two track days on them and they held up better then I thought once they had some time on them.

If you are are just out for some fun and not pushing the Boss to the limit they can work, they will last a long time. I finally found a set of the 295's in the NT05 and now mounted them for my next track day. I need to see how they work since the sizes are not the best for the Boss setup.

Short answer to your questions is 555's will work but only if you are driving to the extreme. I even ran Sebring with the them and stayed on the track just fine. However the Boss is beyond what these tires are capable of, good thing I am not. It also depends on your budget, the 555's will last longer and the price is right.

 

Did you see that Steeda just brought out their copy of Sam's bar, at nearly twice the price?? (though appears it may come with the billet body links? Doesn't explicitly say so)
Wonder what Sam's take is on this, considering it's a rather blatant rip-off.

Strano, $189
http://www.stranoparts.com/partdetai...D=80&ModelID=5




Steeda, $349

http://www.steeda.com/store/ford-mus...r-swaybar.html

 

I'm not the person suggesting which setup to run, but clearly if you look at all racing organizations that allow the use of Mustangs (S197 in particular), you will notice that the Teams/Drivers use square setups. Do you think that it is for tire wear or maybe, just maybe it's because maximizing the front and rear footprint leads to faster times? I would guess that the majority of Boss owners won't leave the car as is and will at least change the bars, springs, or shocks. In general, the rear bar is to stiff, the springs too soft, and the shocks need a lot more range of adjustment. As soon as you increase your lateral grip from factory stock (via tires), you just compromised Ford's Pirelli staggered setup. Any number of unintentional suspension changes (camber, lowering, tire compound and width, weight, etc.) will also change the dynamics of the factory setup. How many know that Ford engineered the Boss FSB bushings for preload adding an X amount of, what could be considered, spring rate? This is at factory ride height. What happens when you lower the front? How does that affect the bushing curve? Unbolt the endlinks and see the bar spring up.

Just this past Friday I went to an all day test&tune session and found 4.3 seconds with changes to bar, tire pressures, and shock settings. My main purpose was to get rid of the mid corner push and help turn in. I would say I did pretty good, but still need much further testing.

All I'm saying if you campaign a specific setup, back it up with logged data or results, race event results. 'I just passed 4 Corvettes on the back stretch', doesn't cut it. I would hate to see people spend good money on a staggered setup only to find out soon after that it pushes severly as soon as you change out part of the suspension.

Dave

 

Or is Grand-Am GS is a spec class and all the cars have to run the same size tires? Nobody is suggesting improvements can't be made but with the stock suspension the car is setup for staggered tires. Lots of good info here so keep it coming.

 

Scott, which 18x9/10 wheels did you get? And, what size tires did you put in the front?

 

I believe they have to run the same tire size by car (that is, Mustangs and BMWs can run different sizes, but all Mustangs are on the same size tires).

Also those cars have significantly better dampers with a minimum 3-way adjustment.

The street versions of the BOSS may be set up for a staggered setup from the factory, but that can be changed. The street attitude of the car is much less important, considering I won't be driving anywhere near the vehicle's performance limit on my way to work, and I won't be using the factory tires at the track.

Interesting comparison of Strano bar vs. Steeda bar. Steeda looks pretty nice too but at 2x the price, forget it.

 

I like what you're thinking!

 

Hey Dave, I'm very interested watching the suspension setups you're working with to see what you think. I'm still grinding out gains from the factory setup by adjusting braking points and driving lines compared to the GT500. I want to wring out as much performance as I can from the factory setup before attempting significant suspension changes.

I've also been slow modding to make sure I know I'm getting gains from them in terms of lap times. Everything I've done so far I've had the opportunity to measure lap time improvements. Also getting the opportunity to drive a stock LS on track back to back with my own car showed me how more aggressive pads, wider tires and additional negative camber showed a clear improvement.

If you get the opportunity to do any comparisons of the stock setup versus modded with the same driver, that would be really helpful to know how much improvement can be gained. I'm not planning on any suspension changes this year, but the mod bug always bites and once I've plateuaed in improvements I'll probably get antsy for more/better

 

I'll do what I can, but finding time to put it in writting is limited. I can tell you that I'm on my 3rd set of rear shocks all while working out the bugs in each. Factory Boss>AST>Penske. BTW, I'm keeping the bars from Strano!

Dave

 

Strano noted this last year when the car was first being introduced, said it was his biggest problem with the car, followed by the too-soft springs, as a preloaded sway bar will present problems if anything else is changed (ride height, spring rates, etc.
I think what Ford did was find a way to give a decent ride/handling compromise for the street and mild road-course work.
If you're truly serious tracking the car, my guess is you'll have the problems Dave mentions when the changes he and John mentioned are made, then you're back to the same basic 3 link Mustang since the intro of the S197. The specific tuning Ford did is great, but they didn't change the platform, and once anything in their tuning is altered, you realize it was designed as a group, all the pieces together.

 

Just to clarify, with the use of the '>' symbol, are you simply indicating the progression of your rear shock testing or actually suggesting that the Factory Boss shocks are 'greater than' the others. I assume the former, but wanted to clarify.

 

Good point, I was wondering the same thing.