S197 Boss Lite - 2011 Mustang GT Build Thread Profile - S197 Mustangs

[stevbd]

Where exactly on the body was the harness rubbing?

On the passenger side front of the engine where the engine harness tucks under the valve cover.

Random misfire 2011-2014 Coyote - check this section of engine wiring harness

I haven't seen a post on this: If you have random misfire problems, carefully check the engine wiring harness in the area of the lower right-hand front corner of the passenger side valve cover. On my 2011, there is a gray plastic fastener which attaches the harness to a metal tab on the bracket...

trackmustangsonline.com

 

[stevbd]

Update on the Ram Concept 9.5 twin disc clutch and AL flywheel. With this setup you really need to remove the clutch pedal helper spring.

This clutch is noticeably lighter than stock and together with the stock helper spring, it was creating this problem where on the bottom half of the pedal travel, the pedal was slow to come back up, and then in the top half the pedal would spring back with more force than expected. Hard to modulate. Worse, on track at redline the clutch pedal was sticking on the floor for a moment and was slow to return upwards.

Removing the helper spring fixed these problems entirely and as of right now I’m loving this clutch with no spring at all. When you see how the spring is installed you can see the problem. It’s oriented so that the spring is most compressed in the middle of the clutch pedal travel, and extends at the top and bottom.

The 1500 rpm resonance of the AL flywheel continues to annoy me slightly. I thiiiiiiink to do it again I’d stay with the stock flywheel just for daily drivability but it’s a close call. At the track I love it. Downshifting is awesome and so much fun.

 

[stevbd]

This sucker is surprisingly stiff, internet says 200lb/inch. It’s hard to compress.

 

[stevbd]

The shocks were gone on my Cortex rear coilovers so I rebuilt them using standard Koni 30 dampers. I used the same part number that Cortex uses.

I bought these coilovers second hand so I didn’t feel comfortable bothering Cortex for too much tech support on new replacements. Plus I just wanted to fix them quickly and get back on the road. Cortex says they custom valve these dampers so I don’t know exactly how much different they are from the standard ones I bought from Koni. But the new ones work great imo.

 

[stevbd]

I knew the old ones were done but I didn’t appreciate just how done until I got them out.

 

[stevbd]

 

[stevbd]

As I was getting all this little stuff sorted out I made it back out to our local track, Palmer, a couple of times recently. Between car problems and life getting in the way a bit, i hadn’t driven there in a couple seasons.

The first day back with the clutch pedal spring problem and the blown rear shocks and on some worn out 275 hankook rs4s, I was able to run about 1.56 minute laps. Handling was even worse than I expected with no rear shocks.

Day 2 with problems fixed and 305 3Rs, the car was amazing, fastest it’s ever been, 8 seconds faster than day before which wasn’t really surprising but also 3 seconds better than my prior best. Better yet the car just ran and handled great. Super fun and satisfying day as this car has been beating me up a bit. I feel like we made up and are in a better place going forward lol.

 

[stevbd]

Cool shot of Palmer, hidden in there is a Mustang coming down off the mountain.

 

[stevbd]

T1 at Palmer

 

[stevbd]

Camber plates create wild looking angles with the inside front tire in corners. But somehow it all just works as everyone knows.

 

[stevbd]

Off topic but my buddy’s very sweet Exige is always a hit at any car show or track day.

 

[GAR944]

Was curious about your "lots of granite to hit". Went to the track website. That is one beautiful place but 100% intimidating place to learn. I don't know if id call it a track or a hill climb circuit.
Love the Saab Viggen also.

 

[stevbd]

So I was away from track driving for a minute and I’ve come back to my old problem of delaminating Goodyear 3Rs on the front outside shoulders on track. I rotate my tires but the problem starts on the front and by the end they all look like this.

Yes I definitely pushed this set too far. Don’t do this it’s not safe.

 

[stevbd]

In the process of trying to figure out root cause, I think I’ve learned some lessons, and also found that I’ve been given (and repeated on here) some advice that isn’t quite correct:

1. Take tire temps with a probe type pyrometer. Temps don’t lie. I was fixated on hot tire pressures but temps are super useful additional data. My temps on the failed front tires, which are probably a little low but close to accurate, were 135 outside, 150 middle, 170 inner.

2. When it comes to negative camber, more is not always better. When I’ve asked how much front camber on an S197 on track, I’ve been told “all you can get.” I think I’ve found that too much is too much.

3. Toe out is fun and creates nice responsive turn in, but it can also destroy the outside edge of your tire.

4. Cold shearing. I wasn’t aware of what this was. As my tires kept failing like this, I thought I was overheating the outside edge and kept thinking about how to get more negative camber. Just the opposite, 135 is freezing cold for a 3R, and I’ve got too much neg camber. And way too much toe out. I think the outside edge is literally blowing in the wind going down straights and then is immediately getting thrown into corners at way too low a temp. The rubber is cold and stiff and mechanically shearing instead of being pliable and wearing properly.

5. “All the camber” plus any resulting toe out is a bad approach for these tires. I need to set my toe to zero on the track and back off the camber a bit.

6. I run stock 11-14 front LCAs. I may need to upgrade to stiffer bushings to maintain alignment better under braking. But I think I will start with the steps above, including reducing my neg camber slightly and getting toe set to zero or a smidge of toe in with about 3 degrees camber.

7. Track alignment depends on the tires and tire sizes you’re running. It’s not a set and forget thing. What works for one tire doesn’t for another. See #1, tire temps.

So that’s my mini confessional and lessons learned. Many of you will read this and say I told you so — especially the part about trying to adapt a street alignment to a track day with big sticky tires.

Anyhow, through all of the above my goal is to get more heat in the front outside edge of my 3Rs, and more even heat across the tire face. My understanding is I should expect the inner to be a little hotter on front due to neg camber. But 35 degree spread is way excessive.

Any additional advice or feedback is much appreciated.

 

[Junkyard Dog]

How much toe out?

Is it possible that the problem is the toe out and not the camber at all?

 

[dave2278]

I currently run the Goodyear 3, am considering going to a 3R for track only.
I run -2.75 camber and 0 toe and my tires have been great, temps very even across the tire.

I do have the GT500 control arms which are much more firm and provide much better feedback and of course less deflection in the bushings.

 

[stevbd]

How much toe out?

Is it possible that the problem is the toe out and not the camber at all?

Very possible. I don’t know my exact toe out. It’s set to zero in the street setting. I’ll have it measured on the current setup before they move it to zero for the new track alignment.

 

[stevbd]

I currently run the Goodyear 3, am considering going to a 3R for track only.
I run -2.75 camber and 0 toe and my tires have been great, temps very even across the tire.

I do have the GT500 control arms which are much more firm and provide much better feedback and of course less deflection in the bushings.

I didn’t have this problem with the SC3. What kind of temps are you getting across your front tires with that setup?

Double check this but my understanding is that ford used the same LCA for all models from 11-14, and the design includes the GT500 improvements from prior years.

 

[dave2278]

I didn’t have this problem with the SC3. What kind of temps are you getting across your front tires with that setup?

Double check this but my understanding is that ford used the same LCA for all models from 11-14, and the design includes the GT500 improvements from prior years.

Mine is an 05, so the GT500 is an upgrade for me, can’t speak to the 11-14.

After a hot session, here that is usually 25 or 30 minutes I have a 7-8 degree spread from 160-168 or so. I don’t know if that good or bad but it works for me, and that’s a 275 at 32 psi hot

 

[stevbd]

I’m still wondering why I’m having this problem with the 3Rs but not other tires. I wonder if the compound in the 3R needs to get hotter than other tires to work and wear properly. It’s well known that you need to get more heat in them before they grip.

Maybe @blacksheep-1 or @Bill Pemberton or one of the many other tire experts on here will see this and chime in.