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Stability at Speed and Under Braking

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How is the LS stability at 130-140?
How about under hard braking from say 140-70?

Most of my track time is at Mid-Ohio and that's pretty typical scenario on the back straight. Anyone here have any time at Mid-Ohio in a Boss? Wondering what your thoughts are as it is considered a fairly technical track?
 
I can only say from 120-125 in a Boss and it's fine. I'm sure a couple of other members with more experience than me will be along shortly.
 
150-160 at BIR down the front straight and it's stable as can be in a "regular" Boss with an LS wing. Turn 1 is a banked 60 degree right hander so there's no braking involved, just a little pucker factor :eek: Turn 3 is about 130 down to 50 and it's pretty stable. You will get a little "tail wag" due to the brake dive, but it's not a huge deal. Here's what the car looks like heading into Turn 10 which is probably going from 130-60:



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And here is going into Turn 3:



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I posted this over at TMS but read through it and I've "BOLDED" (yes I used that as a verb!)

First Track Day Review

About me……….Last track car was a ’06 Mustang GT with the FRPP handling pack, Gt500 Brakes, cooling ducts camber lower rear control arms, etc, etc, etc. I had about 15 or so track events (log book total was about 6500 miles track miles with that car, gave the book to the new owner) with various clubs, not really that fast just out to have fun.

Now onto the Boss 302………

I got my Boss in June 2011, the car sat and only got about 1100 miles on the street, because I‘ve been busy with work and my son's activities, not to mention it is summer down here in Florida and it’s just to doggone hot.

My main reason on getting the Boss is I’m buying into the hype of a track ready Mustang. I’m having visions of Ford’s version of the Porsche GT3; I know its not in the same league a totally focused racecar ala GT3, but track ready never-the-less.

With my old Mustang I was always wishing for about another 1000 rpms to carry me further without having to lift or grab another gear along with 100 or so horsepower and the torque to go with it…….

So my thoughts on a lap of Sebring?

Please remember, I’m no hot-shoe…..

Coming down the front straight, I can carry more speed, glancing down, 120ish in 5th.

Turn one braking point, lift, brake hard, brake late; the Boss gets a little light in the rear and gives a little squirm at threadhold, but settles back down with no input required upshift into fourth, trail brake, turn left on the cut in the track.The car rolls over to the right; it can be a little disconcerting but the Boss hooks up and goes where it’s pointed, this is a bumpy turn so feather in increasing throttle, on trackout carrying about 75-80 MPH or so with the Boss engine singing………..mat the throttle!

Squirt through turn two, going faster than I’ve ever gone through there…….

Get over to the right to set up for a hard braking zone and a short, sharp left, into turn 3. Shift into third and trail brake the entry, the Boss loves to trail brake!

Lazy bend through turn four…….. get and stay right into turn five, apex late to the left, again the Boss rolls over a bit but hooks and it’s back down onto the throttle, hard, going under the bridge, apexing the right side of the drive over bridge, nice easy gear change into fourth (I ham fisted here a couple of times and the Boss’s suspension is compliant and you can upset the Boss here unless you are smooth……).

Turn 6 is a big off camber sweeping right turn, this section of the track is off camber and that last shift? Be smooth, you will have lot’s of speed the Boss will push you up to 110 – 120 MPH, with the Boss leaning to the right, and off camber use all of the track trust the Boss while saying a short prayer for the engineers who designed the tire compound, go!

I’m all the way left going under the walkover bridge, lift just as I pass under the bridge, then there’s the braking point, hard onto the brakes, opps a little past threshold and into the ABS ease up just a hair, 110 MPH plus down to 30-35, light in the rear again, loose but no steering inputs required, shift into 3rd (I only go into 2nd here if there’s traffic). Turn right at the Hairpin, late apex, stay off the curbing its really rough, get back onto the power as soon as possible.

I love the Fangio Chicane turns 8 and 9, it’s a right then left ess turn, apex normally, shift into fourth just before 8 or in-between (be smooth keeping the Boss settled, you don’t want to lift going into 9). Staying on the concrete patches the Boss pulls you through with ease, seemed to me the Boss might have a just a hint of understeer exiting turn 9.

Cunningham Corner is fast approaching, this is a sharp right 90 degree corner, the Boss’s brakes are still hot from the hairpin so this braking zone will take a bit longer, I try my best heel-toe downshift 4-3, trail brake the entry, don’t track too far left, this sets you up for 11.

Turn 11 is an increasing radius turn at apex. Mat the Boss’s throttle and keep it planted, this takes you through Collier Curve, the Boss will go through here to the entry of Tower Turn without lifting or shifting at about 90 MPH. Once though 11, focus your eyes all the way to the entry of Tower Turn.

The Boss displays a bit of oversteer thru turn 12. Don’t fret about getting back parallel to the curbing as you enter Tower Turn (turn 13). Keep the Boss planted the Brembo’s will do the rest! Aim for the turn in point.

Yes it looks tight, brake hard, a little loose, turn in, oh! Great joy! There is a little camber here and speed can be gained! Run the Boss all the way out on to the curbing and drink in the speed its intoxicating!

Shift the Boss into 4th before you get to the FIA curbing on the right, now get set for the two really quick left kinks, know as Bishop Bend (turn 15), I try and lightly kiss the curbing with my left tire, late apex……..Carry as much speed as you can, the Boss has more…but I’m not that brave to explore the limit!

As you exit you should be near the left side of the track setting up for turn 15, as you exit 14, get the Boss straightened out and stable, use the brakes, use them late, use them hard, the brakes are hot from Cunningham Corner/Tower Turn, be careful the track is a bit slick here. I try my heel-toe 4-3 (boy I need to work on that)

This is a throw away turn…..well that’s my option anyway, don’t give up speed in Bishop Bend to try and gain it here, off camber and slick you can only go so fast here. Trail brake 14 to get a little front bite and hit the apex at 15. Set the Boss up for where it can stretch its legs into 16. Don't go too wide on the way to 15 entry setup because you don't want the momentum to carry the Boss too far left. This would make the turn in for 16 more difficult and spoil your speed down the long straight.

Turn 16……this is tight with really bumpy curbing on both the inside and out, the Boss didn’t like it one bit and could be knocked about. I really like to stay inside because everyone else goes wide and now I’m carrying more speed so as we enter the back straight plant that right foot as early as you dare, shift 3-4, check the gages, let the brakes cool…shift again into fifth and the Boss will see 140, maybe more….but things happen real fast at that speed…….

Now we approach Sunset Bend, there are many ways through here I like this……for the 180-degree right turn a 17 and 18 combination. This line uses 2 braking zones into 17. I brake the Boss moderately hard while still going straight, then turn in slightly towards the corner worker and the wall, brake hard. Apex late there’s a couple of old painted lines I use. If I hit my marks just before I go under the bridge there is a big dip in the track the Boss soaks this up and we motor through. I normally try to apex 18 right where the entry to the pit lane begins. There's normally a cone there and a good apex reference point.

Apex this late. Feed the machine, nice steady increase on the gas…..

The Boss pushes us up to the trackout point right next to the left wall just past the walkover bridge supports.

Fly down the front straight, shift 4-5 and set your sights for the turn-in point for #1.

Rinse and repeat.

OK the BOSS 302, My Boss is Competition Orange with Recaro Seats and Torsen Differential.

1. The setup.
- Maximum Motorsport Camber/Caster Plates: 2.1 Degrees Negative Camber all the Factory Caster, Zero Toe

- FRPP Brake Cooling Ducts not the best IMO because of fitment issues covered on other treads

- Transmission Cooling Scoop

- Square Track Tire Setup – GT500 Wheels Painted Mat Black, Nito NT-01 275 / 40 / 18

- Sam Strano’s Rear sway bar: 3-position Adjustable, 22mm (7/8 inch) Tubular: set to the middle position

- Carbotech XP12 on the front and XP10 on the rear

- ATE Super Blue, first time with this normally I use Motul RBF 600

- Screen in lower fascia opening to keep debris out of the condenser

- and a dead petal...........

2. My options.

- Seats, I had Sparco seats in my old car, but these (Recaro) are light years ahead of the stock stuff.

- The HI-Po 302, what can I say that’s not been said? It rocks, pulls all the way to redline with no drop off in power that I can feel.

- Suspension, a little soft yes there’s some brake dive, yes here’s some body roll, but once the Boss leans over it sets and scoots. A little loose at times under really aggressive braking, but only just a bit it never feels like it wants to come around. But this is in a straight line……I wonder? Why? Just the weight transfer?

- Brakes, I ran into the ABS a couple of times going into the hairpin, I had the FR500s ABS ECU etc, on my old car, so I’m now a little less aggressive. No fade with the cooling, fluid and pads I ran. Great trail braking!

- Cooling, I did get the stock temp gauge up into the ¾ area a couple of times but maintenance throttle on the back straight settled that back down. I guess I’m just not the madman some others are, and/or being near sea level helped. But it was also not as hot as some other days I’ve been at the track.

Bottom-line - The Boss is way more capable that I am, the car will take years for me to get brave enough, I mean to learn the car!

What else do I want?

-Oil Separators
- Real Race Seats
- Four Point Roll Bar with Harnesses
- Real Gauges
- Air-to-Oil Cooler (Insurance)
- Maybe two piece rotors for the front and that’s it……….

Well maybe lower it and then put on the splitter oh wait that means coilovers and a bigger rear wing, well may not I just want to have fun and not have a new money pit….then again!

Please remember these are my opinions and I’m just a regular guy who likes to play with cars…………… any typos? Tuff!
 
Boss_302 said:
- Brakes, I ran into the ABS a couple of times going into the hairpin, I had the FR500s ABS ECU etc, on my old car, so I’m now a little less aggressive. No fade with the cooling, fluid and pads I ran. Great trail braking!
I'm pretty sure Ford Racing is coming out with a 302S ABS ECU that is plug and play in our cars. I was told it takes about 10 minutes to swap at the track.
 
5 DOT 0 said:
Boss_302 said:
- Brakes, I ran into the ABS a couple of times going into the hairpin, I had the FR500s ABS ECU etc, on my old car, so I’m now a little less aggressive. No fade with the cooling, fluid and pads I ran. Great trail braking!
I'm pretty sure Ford Racing is coming out with a 302S ABS ECU that is plug and play in our cars. I was told it takes about 10 minutes to swap at the track.

That would be great, best of both worlds!

302S race module would allow higher deceleration rates on sticky tires!
 
One thing that's been observed here that I can attest to - on a base Boss at least, rear aero was a big improvement for me in high-speed initial brake bite wiggle. I swapped for a FRPP GT500 rear wing, and it really calmed down the rear end at speed. Also made high-speed turns like the Kink at Road America feel quite a bit more controlled, and faster of course. Wouldn't expect an LS to have that issue with it's superior aero, but the base Boss definitely should have come with something better.
 
Yea I felt like the car was more planted going through Turn 1 at BIR at 140 mph after I added the LS wing. I don't have any split time data to support it other than my butt dyno.
 
I was up in the air about that too. I am not sure if it's true that the LS has more downforce or not - haven't seen wind tunnel tests on that - but I wanted to try the "non-hole drilling" approach first. I got exactly what I wanted stability-wise out of the GT500 wing, so I doubt I'll explore that any further now. I am quite content with it :)
 
LateApex said:
I was up in the air about that too. I am not sure if it's true that the LS has more downforce or not - haven't seen wind tunnel tests on that - but I wanted to try the "non-hole drilling" approach first. I got exactly what I wanted stability-wise out of the GT500 wing, so I doubt I'll explore that any further now. I am quite content with it :)
Ford Racing has done the wind tunnel testing on the various spoilers, including the splitters, and told me about the difference. They said it was very minor and that only a Pro would be able to tell on the track so don't worry about it. They also said lowering the stock Boss splitter 1" had a similar effect to adding the LS splitter. The 302S hood also decreases lift which in effect increases downforce.
 
jas427 said:
- Screen in lower fascia opening to keep debris out of the condenser

Could you please send pictures of the screen you installed on the front of your boss. Just 2 days of tracking and the condenser is already showing its wear. Thanks John

I cut the screen wider / longer and taller than the opening, I removed the radiator cover and slid the screen down from the top. Four zip ties secure the screen. I also notched the screen to clear the sensor in the lower grill

DSCN0165.jpg
 
Boss_302 said:
I cut the screen wider / longer and taller than the opening, I removed the radiator cover and slid the screen down from the top. Four zip ties secure the screen. I also notched the screen to clear the sensor in the lower grill
Did the same but added a few wraps of wire for security. I was afraid the metal may cut the zip ties over time.

CIMG2209.jpg
 
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1
The car feels to me very stable. At speeds in the 145-150 range it feels good. It brakes very well at those speeds. I have ran two different tracks with some very high speeds (140-150) that brakes down to lower speeds than 80. Just make sure you have good fluid, rotors, and the right pad combination....
 

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