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Going Square General Noob Questions...

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Tulsa, OK
Grant 302 said:
You didn't ask for other suggestions, but I'd try to get a whole GT or GT track pack strut/shock, spring, and sway setup. I've seen full take off sets for cheap on SVTP. Make your own V6 performance pack...

I've got all that stuff I'd be willing to sell ::) Trying to fund a racecar over here lol
 

TMSBOSS

Spending my pension on car parts and track fees.
7,530
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Exp. Type
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Illinois
Step one. Safety stuff.

Helmets and such

Step two. Driver mods.

Track time with competent instructors.

Step three parts.

Tires, wheels, brake fluids and pads.

Step four.

Hold on to your wallet...prices expand exponentially.
 
Voltwings said:
Well all this talk about being nice to noobs means i guess it's time to stop being a lurker and ask some questions haha ...

So back to the topic at hand, i spend a good deal of time browsing this forum because my GF and i have recently become more involved in track days, sadly ... neither of us are in a BOSS. I have a '13 5.0, and she has a '14 v6, and the cars are set up pretty similarly, and both running square set ups.
I want to focus more on how i have her car set up now because, not to sound cocky but, if i get in an "oh shiznit moment" i think i'd handle it a little better than her lol...

Shes got a v6 like i said, running my stock GT rims ( 18 x 8 ) with a nitto Nt01 tire on them, so should be enough tire for her stock HP and stock weight car. That being said, is it still safe to assume our cars will (should) understeer from the factory, even though our set ups arent staggered like a boss? Even the track pack GT and V6 (hers is a base model) still run a square set up, so i'm assuming the reason they run a thicker bar in the rear is to induce that understeer?

The thicker bar in the rear is generally to reduce understeer or to induce oversteer (which are two ways of saying more or less the same thing), understeer being the tendency of the front of the car to lose grip before the rear, whilst oversteer is the opposite.

I believe the V6 base rear sway bar is 22mm. The performance package rear sway bar is, from what I can tell, the same as the GT: 24mm. If the rear bar you're talking about is from the GT500 SVT performance package, then it's 24mm, same as the GT.

The Boss 302 has an even larger bar in the rear, 25mm for the standard Boss and 26mm for the Laguna Seca, but both of those cars have a staggered tire setup, so the thicker rear bar at least partially offsets the change in front to rear tire balance.

The sway bar isn't the whole story, though. You also have to look at the springs. I'm not sure what those rates are for the base V6. It's telling, however, that the Laguna Seca has both the stiffest rear sway bar and the stiffest rear:front spring balance (193 lb/in rear, 137 lb/in front) of all these cars, which suggests it's probably more prone to oversteer than the rest.


I have her set up on her stock RSB right now, but also have a thicker GT500 bar i could throw on there as well... I Imagine we would rather flirt with the line of neutral / understeer as opposed to the line between oversteer / neutral.

My advice (for what little it may be worth) is to, before doing anything, get some seat time in the car with the stock suspension. Figure out how the car is balanced right now and start making changes only for those things you believe are limiting you. You may find that the stock suspension suits you very nicely.

I've found my GT's suspension (stock 2014 Track Package) to be surprisingly neutral and easy to control. It understeers slightly at the limit (but feels quite neutral mid-corner to my novice posterior), but inducing neutrality to oversteer is very easy, either by lifting the throttle or by adding power, or by using trailbraking (i.e., continuing your braking, at a lower amount, into the corner). The end result is very controllable and fun to drive. Needless to say, I was very surprised at this -- I thought the stock suspension would be a wallowy mess. But it's not. It would tend towards a little more oversteer if I had camber/caster plates. As it is, I'll be replacing the shocks and struts with coilovers, but only because I need camber/caster plates and I may as well put coilovers on in the same operation, and pay for the labor only once. My choice of spring rates and ride height is for the purpose of preserving as much of the stock suspension's handling characteristics as I can while roughly doubling the spring rates.


This will only be our second weekend event this weekend, so we're still trying to learn the way these cars drive, but i just want to do my best to have her car set up so shes able to go out there and have fun (safely). Its a lot of money, so the last thing i need is to be broke AND have a temperamental girlfriend haha(we live together, cant get away!). Thanks guys.

If safety is your primary concern, then most certainly, the stock suspension is going to be that. It's not necessarily going to be the fastest setup, but since you guys are essentially brand new to this, going fast should not be your concern. Driving consistently well while feeling the car out should.

You most definitely want to take care of brakes first. Of all the systems in the car that you cannot afford to fail on the track, that is it. At a minimum, that means going with really good high-temperature fluid (I'm a big fan of Castrol SRF myself if only because you won't have to bleed the brakes all the time) and pads. In fact, if you're thinking about spending any reasonable amount of money, you might consider putting 4-piston Brembos on the front of both cars and, especially with the 5.0, running brake ducts. But I'd see how the brakes hold up with fluid and pads before going that far.
 
roadhouse said:
I've got all that stuff I'd be willing to sell ::) Trying to fund a racecar over here lol


I bought a cheap set of Boss take-offs for my car, so shes currently running my base GT suspension + Eibach springs, but i may take you up on that.

kcbrown said:
The thicker bar in the rear is generally to reduce understeer or to induce oversteer (which are two ways of saying more or less the same thing), understeer being the tendency of the front of the car to lose grip before the rear, whilst oversteer is the opposite.

1. I believe the V6 base rear sway bar is 22mm. The performance package rear sway bar is, from what I can tell, the same as the GT: 24mm. If the rear bar you're talking about is from the GT500 SVT performance package, then it's 24mm, same as the GT.

2. The sway bar isn't the whole story, though. You also have to look at the springs. I'm not sure what those rates are for the base V6. It's telling, however, that the Laguna Seca has both the stiffest rear sway bar and the stiffest rear:front spring balance (193 lb/in rear, 137 lb/in front) of all these cars, which suggests it's probably more prone to oversteer than the rest.


3. My advice (for what little it may be worth) is to, before doing anything, get some seat time in the car with the stock suspension. Figure out how the car is balanced right now and start making changes only for those things you believe are limiting you. You may find that the stock suspension suits you very nicely.


4. If safety is your primary concern, then most certainly, the stock suspension is going to be that. It's not necessarily going to be the fastest setup, but since you guys are essentially brand new to this, going fast should not be your concern. Driving consistently well while feeling the car out should.

5. You most definitely want to take care of brakes first. Of all the systems in the car that you cannot afford to fail on the track, that is it. At a minimum, that means going with really good high-temperature fluid (I'm a big fan of Castrol SRF myself if only because you won't have to bleed the brakes all the time) and pads. In fact, if you're thinking about spending any reasonable amount of money, you might consider putting 4-piston Brembos on the front of both cars and, especially with the 5.0, running brake ducts. But I'd see how the brakes hold up with fluid and pads before going that far.

1. All the sizes you listed are correct.

2. To be honest, i have no idea what the spring rates are on the Eibach pro-line, something i should probably look up though.

3. I agree with this 100%. The only problem is shes new to cars lol.
How does it feel?
-IDK, my tires squealed a little on turns x and Y
Ok, front or rear
-i dont remember
Did the front push out or did the rear come around
- It was hard to tell, i think the rear?

... Makes dialing in her car very difficult when thats what you're working with haha, but yeah, i suppose just leaving it alone and letting her figure those things out is best. Its just hard when you want to set the car up "the best," but end up just having to leave it alone.

4. I agree. Like i said, its just hard to not want to buy things to make it "better."

5. Both cars run Amsoil DOT4 (all amsoil fluids is where a LOT of our budget goes -_-), and now that Vorshlag has brake duct kits for the 13-14 that are actually useful we'll be grabbing her a set of those. I had the FRPP kit in my '13, and the ducts are way too far outboard in the foglights, i still melted the backing plate on my stock pads my first time out. Had 2 deep impressions from the pistons on each side lol... yikes.
 
Voltwings said:
I bought a cheap set of Boss take-offs for my car, so shes currently running my base GT suspension + Eibach springs, but i may take you up on that.

1. All the sizes you listed are correct.

OK, so putting on that GT500 bar should make the V6 match the performance package in terms of the sway bars, I think. The problem is that I don't know if the front bar you have is the same (the part numbers are different), so tread carefully. The performance package has the 34.6mm bar up front. You can (and should) measure hers. If it's the same, then you should have the same bar configuration as the performance package in the end, assuming there's not a rate difference in the front bar between the base V6 and the performance package. I don't seem to be able to find any data on the diameter of the base V6 front bar.


2. To be honest, i have no idea what the spring rates are on the Eibach pro-line, something i should probably look up though.

I don't believe you'd mentioned those springs before now. That potentially changes things a bit, but it doesn't look like it would change it by a whole lot...

If the kit you're talking about is this, then the front spring rate is 159 lb/in, while the rear is 193 lb/in. But the rear is progressive, which means the rate increases as it compresses, so it's really a range of rates. In any case, if those rates are accurate, then the relative balance due to the springs should actually yield a little more push (understeer) than the performance package springs would, but not very much. I expect you'd have to be a very skilled driver to really notice the difference.


3. I agree with this 100%. The only problem is shes new to cars lol.
How does it feel?
-IDK, my tires squealed a little on turns x and Y
Ok, front or rear
-i dont remember
Did the front push out or did the rear come around
- It was hard to tell, i think the rear?

... Makes dialing in her car very difficult when thats what you're working with haha, but yeah, i suppose just leaving it alone and letting her figure those things out is best. Its just hard when you want to set the car up "the best," but end up just having to leave it alone.

The problem is that "the best" has to be defined by the driver, so yeah, since she isn't sufficiently familiar with the car or with high performance driving to really know what the car is doing, it's best to leave it alone until she does.

I might be inclined to put on that GT500 sway bar anyway, if only so that the car has roughly the same balance as the performance package version of the V6 model, but only if the front bar is the same as the performance package front bar.


4. I agree. Like i said, its just hard to not want to buy things to make it "better."

Resist the temptation! :)

Instead, direct your efforts into making the car truly better, i.e. put things on it that will make a noticeable difference.


5. Both cars run Amsoil DOT4 (all amsoil fluids is where a LOT of our budget goes -_-),

The Amsoil stuff is okay (dry boiling point of 580 degrees and wet boiling point of 380 degrees), but you can do better. SRF has a dry boiling point of 590 degrees but, more importantly, a wet boiling point of 520 degrees.


and now that Vorshlag has brake duct kits for the 13-14 that are actually useful we'll be grabbing her a set of those. I had the FRPP kit in my '13, and the ducts are way too far outboard in the foglights, i still melted the backing plate on my stock pads my first time out. Had 2 deep impressions from the pistons on each side lol... yikes.

Does your GT have the Brembo brake package? If not (and I suspect not, based on the wheel size you mentioned), I highly recommend that you get the 4 piston Brembos up front soonest if you're melting brake components despite having brake ducts. The reason I recommend the Brembo setup over others is the plethora of brake pads and other supporting hardware that's available. Vorshlag sells the kit for $1200, and that will be money well spent.
 

Grant 302

basic and well known psychic
Voltwings said:
I bought a cheap set of Boss take-offs for my car, so shes currently running my base GT suspension + Eibach springs, but i may take you up on that.

Ignore what I posted about your car before. Leave it for now, you should be fine with this setup if she's got your sways and struts/shocks...or tell us everything that came from your car.


roadhouse said:
HA! It's a damn tripod! Fixed the sig pic 8)
Perfect. ;)
 
My advice, don't modify her car alot, since she's still learning. Let her skills and knowledge catch up to the car before you start making changes. Keep the changes simple overtime, like tire pressure, tires and pad upgrade etc.
 
kcbrown said:
OK, so putting on that GT500 bar should make the V6 match the performance package in terms of the sway bars, I think. The problem is that I don't know if the front bar you have is the same (the part numbers are different), so tread carefully. The performance package has the 34.6mm bar up front. You can (and should) measure hers. If it's the same, then you should have the same bar configuration as the performance package in the end, assuming there's not a rate difference in the front bar between the base V6 and the performance package. I don't seem to be able to find any data on the diameter of the base V6 front bar.


I don't believe you'd mentioned those springs before now. That potentially changes things a bit, but it doesn't look like it would change it by a whole lot...

If the kit you're talking about is this, then the front spring rate is 159 lb/in, while the rear is 193 lb/in. But the rear is progressive, which means the rate increases as it compresses, so it's really a range of rates. In any case, if those rates are accurate, then the relative balance due to the springs should actually yield a little more push (understeer) than the performance package springs would, but not very much. I expect you'd have to be a very skilled driver to really notice the difference.


The problem is that "the best" has to be defined by the driver, so yeah, since she isn't sufficiently familiar with the car or with high performance driving to really know what the car is doing, it's best to leave it alone until she does.

I might be inclined to put on that GT500 sway bar anyway, if only so that the car has roughly the same balance as the performance package version of the V6 model, but only if the front bar is the same as the performance package front bar.


Resist the temptation! :)

Instead, direct your efforts into making the car truly better, i.e. put things on it that will make a noticeable difference.


The Amsoil stuff is okay (dry boiling point of 580 degrees and wet boiling point of 380 degrees), but you can do better. SRF has a dry boiling point of 590 degrees but, more importantly, a wet boiling point of 520 degrees.


Does your GT have the Brembo brake package? If not (and I suspect not, based on the wheel size you mentioned), I highly recommend that you get the 4 piston Brembos up front soonest if you're melting brake components despite having brake ducts. The reason I recommend the Brembo setup over others is the plethora of brake pads and other supporting hardware that's available. Vorshlag sells the kit for $1200, and that will be money well spent.

I have a set of digital calipers so i can measure the front bar this weekend. My GT does not have the brembo package, but its something i have been working towards. The hard part was the very high upfront costs of getting two cars track ready: Spare rims and tires for both cars to save the street set. Spare brakes, all new fluids, a little of this, a little of that... I think we're pretty set between now and our next track day in December (we try to go every other month) as far as parts go, so we'll focus on her driving.

She flustered herself this past weekend and blew a few downshifts (poor things only been driving stick a month, the track was probably terrifying for her) so she just left it in 3rd and really focused on nailing the corners. Hopefully when we do our post op evaluation this weekend, look at tire and break wear, and otherwise get the cars back to street trim we can get some useful information from this.

I understand this is really difficult trying to tell you guys what she is trying to tell me, but i really appreciate everyone giving me a hand in trying to understand this so we can hopefully get these cars set up properly for how we like to drive. I just got solo qualified and bumped to blue this past weekend, so maybe i can start taking her for rides with me and it would really be beneficial when we're both in the car at the same time.
 
6,363
8,190
FWIW a fast and dirty way to measure a sway bar is to place an open end wrench on it.

Here's a link to the phoenix brochure
http://www.phoenixperformance.net/brochures/PhoenixBrochure_Mustang14.pdf

although there's no real usable info on it. I can tell you that 90% of the parts on the t2 (and the IMSA GS car) are over the counter ford products with a Hotchkis sway bar thrown in now and then. If you call and ask for Andrew or Kurt they will walk you through the process.
 

dmichaels

Papa Smurf
547
30
CT
I'm planning to try my new square setup this Friday. BFG R1's 275/35/18 on PF01's. I have a GT TP with stock sways, but SR springs and Koni STR.T shocks/struts. I tend to like a slightly more oversteer happy setup, so I purposely am going square.

I recently ran my car with the OEM wheels at Thompson (after putting in 4 or 5 days there with my staggered other track setup of 255 front 275 rear) and I was consistently a second faster and the car rotated much more. It was not tail happy, but it rotated very well for lift throttle and power oversteer. Didn't notice a different during trail braking. I was actually quite surprised at how much of a difference going from 275 rear to 255 rear (and keeping 255 front) actually made.

Great input in this thread. I sure hope I like my square R1 setup, seeing as I sort of have 8 of the same size tire in my basement :)
 
6,363
8,190
Let me offer this bit, keep the rights on the right and the lefts on the left when you rotate them, don't "X" them like regular tires. At some point you can swap them (turn the outside to the inside) but keep them rotating in the same directions for their entire life span.
 
blacksheep-1 said:
Let me offer this bit, keep the rights on the right and the lefts on the left when you rotate them, don't "X" them like regular tires. At some point you can swap them (turn the outside to the inside) but keep them rotating in the same directions for their entire life span.

Are you talking slicks? Or all tires in general?
 
blacksheep-1 said:
Let me offer this bit, keep the rights on the right and the lefts on the left when you rotate them, don't "X" them like regular tires. At some point you can swap them (turn the outside to the inside) but keep them rotating in the same directions for their entire life span.

You are talking about a square set up correct?? Are you also referring to directional tires or asymmetrical???
 
6,363
8,190
Slicks on a "square" car, once they start rolling in one direction, I never change that. If you have a "non square" car then you will have to rotate (invert?) them on the wheels so you can wear out the outside of the tire.
As an example your rt frt is showing significant wear on the inside edge due to camber settings and you want to get another day or two out of the tires. Take the rt frt tire and position on the left front wheel, in this manner you can now wear out the (new inside, formerly outside) area of the tire and it will still rotate in it's "correct" position. Once you throw asymmetrical tread patterns at a car then your options are few unless you can rotate them front to back on the same side.
 
Voltwings here are the rate compares of the v6 and GT bars.

v6 bar: 33.2 diameter with 5mm thick wall approximate fea rate 49.17 N/mm
gt bar: 34.6 diamter with 4.4mm thick wall approximate fea rate 51.82 N/mm

I have not measured rates with the s197 bonded bushings so the rates above are just theoretical.

My car has oversteer issues :eek:

I have the Steeda sport 200lb/in front 175 lb/in rear with a 25mm rear stabar and weak Eibach sport dampers.

Running on square 275/40/18 rubber and rear lower control arms in a slight anti squat position, and with a bit too much negative camber in front (about -2 deg.) my Mustang over steers something fierce. even if you are not gassing it just turning in very hard off throttle will get the rear end lose.

switched to a 22mm v6 rear bar last night, will find out if that helps grip coming out of corners.
 

steveespo

Lord knows I'm a Voodoo Child
Moderator
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twistedneck said:
Voltwings here are the rate compares of the v6 and GT bars.

v6 bar: 33.2 diameter with 5mm thick wall approximate fea rate 49.17 N/mm
gt bar: 34.6 diamter with 4.4mm thick wall approximate fea rate 51.82 N/mm

I have not measured rates with the s197 bonded bushings so the rates above are just theoretical.

My car has oversteer issues :eek:

I have the Steeda sport 200lb/in front 175 lb/in rear with a 25mm rear stabar and weak Eibach sport dampers.

Running on square 275/40/18 rubber and rear lower control arms in a slight anti squat position, and with a bit too much negative camber in front (about -2 deg.) my Mustang over steers something fierce. even if you are not gassing it just turning in very hard off throttle will get the rear end lose.

switched to a 22mm v6 rear bar last night, will find out if that helps grip coming out of corners.

Your setup seems to be destined for oversteer, here's why;
Spring rate ratio is too close you either want more front spring or less rear. Depending on your track layout you may want to change one end or the other. Slow/twisty track soften the rear, high speed/sweeping course stiffen the front. Overall this car benefits from more spring rate than less on track but you need a bigger spread especially with square tire setup.

Rear bar can go to 18mm or 13mm(1/2"), this will help traction and corner grip.

Leave the camber alone.

Put more rear tire on it. I run 295/305 setup now and it gets very neutral on exit, still fight a little understeer on entry, my driving style has to change, need to carry more speed and let the car roll through off throttle vs. maintenance throttle to the apex.

Just my observation, you seem to be knowlegable, good luck with it.
Steve

If shocks are worn replace them, uncontrolled springs cause funny handling issues.
 

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