Fiesta ST NASA TT5, Build-ish, Results, Track Videos

[slyez]

New brake issue for any experts.....

After all the work on the front brakes for heat tolerance, the EBC kit was awesome at Laguna Seca. After that event we got back home and did the normal brake fluid flush, oil chnge, pad inspection, etc. We then drove the car around on the road and the brake pedal feels terrible. It travels around half way until it engages the brakes at all, ad woth the engine running, if we keep sustained pressure on the pedal it will slowly sink. We have been researching this issue for days now and have found a few people with very similar issues but no realy solutions (one guy it just started feeling better, the other guy just gave up and traded the car in after a few months). We have changed almost everything in the system except lines. We started with flushing tremendous amounts of fluid through it with a pressure bleeder and manually. We then did many ABS service bleed proceedures with FORScan and also with the Ford IDS software. Still no change. We then swapped the Master Cylinder. No change. Maybe sightly worse even.... We bled like maniacs again (we did bench bleed it as best we could, but fluid still pours out as you try to hook up the brake lines....) Next we got a used ABS complete module and reprogrammed it to our VIN with the Ford IDS. No change at all. We THEN changed both rear calipers, still same. So we are at the front EBC brake calipers now, they worked great when installed, and I do not think it could be the problem as there are no leaks, not sticky pistons, not visible functional deficiencies at all. Any suggestions?



Here are the 2 threads for other people:
https://www.fiestastforum.com/threads/brake-fluid-leak-anyone-else.7356/page-2
and
https://www.fiestastforum.com/threads/brake-job-mistake.10793/

I am also going to start a new thread in the brake section to look for more assistance. Hopefully the moderators wont mind a double post...

 

[slyez]

As an added bonus for anyone able to directly help solve this issue, We will run a "Thank You (Your Name Here)" sticker wherever you want on the car for the rest of the race season, including the National Championships. It can say whatever you want within social reason, and can be up to 8.5"x11" (that's as big as our vinyl cutter will do in 1 shot).

 

[Mike King]

My experience has been that at least three mechanical things can cause this: 1. external leak 2. fluid recirculating in the master cylinder or the brake pressure modulator valve assembly or 3. air sucking into the system when releasing the pedal through a piston seal that is rolled a little. It will be fine under pressure but will suck up a little air each time the pedal is released. This gives a soft pedal. Then there are the electronics. Is there a way to data log what is going on with the ABS module itself? Also the ECM. Look at things like engine load, torque vectoring and wheel speed sensors. Something could be skewed but not enough to set codes causing a dump solenoid to recirculate. Maybe pull the abs fuses and bleed the system again to rule out electronics versus a mechanical issue. I'm no expert but simply brainstorming here.

 

[thecman02]

You guys wouldn't by any chance happen to have speed bleeders on any of the calipers? I've crewed for numerous efforts where they happen to go bad in a manner that they can introduce air, but still not leak. Also had issues with a bad proportioning valve/isolation valve. The valve would sometimes stick in a manner that would give you only two of your braking channels, and then when you really applied brake pressure it would center back up giving you all your braking, but the pedal would sink down substantially (atleast) half a pedal. Not sure of any other weird failures . Maybe check to see if for some reason your pistons are retracting back further than normal; although you said the seals aren't sticking :-(. It isn't an issue I've had in cars, but on motorcycles I had that happen numerous times.

 

[slyez]

Sorry, forgot to update on this. We went through days/weeks of swapping every component in the braking system including ABS module, Master Cylinder, Calipers, and flushing literally gallons of fluid through it with and without ABS bleed from Forscan and Ford proper IDS software.... Nothing worked.... Finally we changed the brake lines back to stock, then to stock in rear only, and now pedal is great again.... I am not certain that the lines were the answer because we also changed back to the original MC at the same time, but either way.... brakes work again...

 

[Erick_V]

2-Added the SVT Focus rear calipers and rotors. We have heard that you only can use the caliper brackets, but we could buy the entire caliper and bracket for ~100$ including the core charge. The main difference between the 2 calipers is the emergency brake cable bracket. If you swap that bracket from one caliper to the other then the SVT rear calipers bolt right into place and brake cable is fine also. Does seem like the lever to caliper ration of the emergency brake is changed, as the brake handle pulls farther now....

Always wondered if this was an option because the brackets are hard to find. I’m assuming you bought it from a parts store?

 

[slyez]

Quick updates:

1-Found a "compatible" 1" master cylinder for our brake booster. It really helps the pedal feel, now there is a very firm pedal with out the overboosted feeling of the stock MC. Didn't take much effort, but there are a decent amount of "lessons learned" and things to buy, that we can share if there is interest.

2-Added the SVT Focus rear calipers and rotors. We have heard that you only can use the caliper brackets, but we could buy the entire caliper and bracket for ~100$ including the core charge. The main difference between the 2 calipers is the emergency brake cable bracket. If you swap that bracket from one caliper to the other then the SVT rear calipers bolt right into place and brake cable is fine also. Does seem like the lever to caliper ration of the emergency brake is changed, as the brake handle pulls farther now....

3-Installed an AIM MXM datalogger and dash in place of our Kart specific AIM Mychron that we have been using. It has CAN/OBD2 connectivity, ad can log and dispay a lot of valuable data and ECU PIDs. It also has 2 programmable DC outputs. One of these we are using to automatically power our wind-washer pump powered intercooler sprayer setup. System has a lot of programmable warning lights, per-gear shift lights, we added Oil Temp, Oil Pressure and Charge Air Temp sensors as well.

4-Started some aero testing on stock EU Diesel Fiesta undertray installation. Initial testing was not good. Water and Oil temps much higher with undertray. We have reinstalled our factory hood with the Versus engineering vents, and will retry the testing with that.

5-We built some braces. Subframe to body, and trunk brace. Easy fabrication, and saved a lot of money...

Getting ready for NASA Championships at Laguna Seca in September!

 

[slyez]

Always wondered if this was an option because the brackets are hard to find. I’m assuming you bought it from a parts store?

yes, got them from rockauto I think?... We were going to rebuild or replace the rear FiST calipers anyway, so it seemed worth a try.

 

[slyez]

Another datapoint.... We are using the EBC RP-1 pads up front. 3.25 track days and they still have pad material enough for another full day at least. Great feel, and good rotor wear also. We have new sets of the brand new SR-11 compound to try next, and will do that this weekend. We are very happy with the EBC brakes and the pad compounds. Also, they are helpful with questions when we call them, so its a big win for our team.

 

[slyez]

Quick updates:


4-Started some aero testing on stock EU Diesel Fiesta undertray installation. Initial testing was not good. Water and Oil temps much higher with undertray. We have reinstalled our factory hood with the Versus engineering vents, and will retry the testing with that.

Tested vented factory hood with the undertray, still way higher coolant, oil and charge air temps. Undertray is a no-go.

 

[slyez]

Yikes! Exhaust melted a hole in the fuel tank! Found the source of the fuel smell that developed 2 days ago, and looks like we may not make it to the track this weekend. Does anyone know if a standard fiesta tank will work with the ST? Thats all thats available in local junkyards.

 

[slyez]

So standard Fiesta is the same tank despite what old internet threads will tell you. I have both in front of me and they seem identical. so for future google searchers.... The Fiesta ST is compatible with the base fiesta fuel tank. Same straps can be used, ST fuel pump fits, all evap connections the same.

Also, I took the heat shield from the base fiesta, and it is also the same as the ST, and I plan to double the heatshield in this area. Anyone with another good idea for protecting the tank, please post it.

 

[M-Sport fan]

Perhaps a fuel cell is in your future??

 

[Erick_V]

Maybe Cerakote the exhaust to cut the temps down? That in combination with heat shielding should solve that issue. I didn’t realize it got that close to the tank. I’m assuming that’s at the 90 degree bend near the rear beam?

 

[slyez]

Maybe Cerakote the exhaust to cut the temps down? That in combination with heat shielding should solve that issue. I didn’t realize it got that close to the tank. I’m assuming that’s at the 90 degree bend near the rear beam?

yes, at the 90. I did double the factory heat shield and adjusted the exhaust hangers with a hammer to pull the exhaust a few mm further from the tank...

 

[slyez]

Sunday, 7-24-22, we took the car to Streets Of Willow, at Willow Springs International Raceway in Rosamond, CA, with the new SR11 compound pads. They were really great!. We drove on them to the track(~450 miles) and drove on them all day, around 50x 1:26s laps. The pads only wore down around .7mm from the drive there and back, and the full day of testing in 100F heat! We have old data from stock brakes and Carbotech x12F/x10R pads. Those gave us a soft pedal halfway through the day, and really soft by end of day.
The pedal stayed firm all day, the deceleration rates were high, 2 times per lap slowing from 110mph, once down to around 60, and once down to around 40. The driver yesterday loved the brake feel, and they did not ever give us any lack of confidence. Very happy. One thing we didn't do however, was to use brake temp paint, as we did not have it with us, so I cannot confirm the peak temps, but we did see red glow at the end of the straight (110-40), so they did get warm.....


Here are links to videos of Streets Of Willow in our Fiesta:
Session from 9/18/21 1:26.9 Toyo R888R
7/24/22 - 1:25.5
7/24/22 - 1:25.9

 

[Mike King]

yes, at the 90. I did double the factory heat shield and adjusted the exhaust hangers with a hammer to pull the exhaust a few mm further from the tank...

You could try some exhaust header wrap just on the 90.

 

[slyez]

You could try some exhaust header wrap just on the 90.

Yes, thanks, thats a good idea. We thought to try it, but with the double heat shields it seems pretty good. If we add the wrap it will likely touch, and t seemed that the non-contact air space may be better.

 

[Mike King]

Yes, thanks, thats a good idea. We thought to try it, but with the double heat shields it seems pretty good. If we add the wrap it will likely touch, and t seemed that the non-contact air space may be better.

You will probably be ok with double heat shields, then.

 

[slyez]

Finalizing the car for NASA Championshipd at Weathertech. The past year of development has given us the best car we can build from the platform, while staying TT5 legal. Plenty of testing and re-testing, and problem solving.....

I can vouch for all of the parts on the car currently, so if anyone is interested here is the final parts combination that we will use in the "wrong car" to compete against a bunch of GR86, S2000, BMW 330, etc. in TT5 in 3 weeks. I added Bold to the parts that made big differences:

-2016 Fiesta ST, race weight ~2750lb with driver
-S280 Turbo, Turbosmart WGA at 14lb and EM diverter valve. Tuned to 25psi at 4000 tapers to ~14 at redline so we stay around 225-230 whp for class legality
-3" turbo back exhaust mostly homemade, with a boughten downpipe that I dont know the brand
-2jr cowl intake
-Mishimoto intercooler with custom water mister and 1 gallon tank in trunk
-Mishimoto Catch Can
-Mishimoto radiator
-Mishimoto Coolant Reservior
-Cobb rmm
-Gripper Clutch Differential
-Fidanza Flywheel
-redrilled front hubs for 4x100
-Advanti 15x9 F, 15mm spacers, Team Dynamics 1.2 15x8 R, 5mm spacers 245/40 F, 205/50 or 225/45 R
-MeisterR GT1 10kgF/11kgR spring
-Base fiesta 21mm FSB with adjustable endlinks
-Homemade rear beam stiffener from 1.25" kart axle
-Homemade front subframe brace and trunk brace (similar to TB ones)
-DNA rear strut brace with diagonals
-~3.8 degrees front camber, +.5 degree caster, 2mm toe out
-~2.2 degrees rear camber, 1.5mm toe out
-Poly bushings everywhere we could
-EBC 300mm Apollo Balanced brake kit
-EBC SR11 front pads
-SVT Focus rear brakes
-EBC Orange rear pads
-Custom brake ducts and backing plates
-Maxima Racing brake fluid
-Custom made front airdam
-Nine Lives Racing rear wing (optional based on track)
-Seibon Carbon hood with Versus Engineering Hood Vents cut in
-Base Fiesta Rear Hatch Spoiler
-FSWerks short shift adapter, and 2" shifter extension
-OMP WRC-R drivers seat
-AIM MXM Dash and logger
-+50lb in spare tire well

-A lot of help from Jerrick at MeisterR and Steve at EBC USA brakes. They took a lot of time answering questions and helping make decisions. There were a lot of other helpers along the way. Also all of the help and encouragement from the forum members! Hopefully the car gives you all a sense of pride.

-Steve
Mountain Top Racing