Installing ATS Brembos on the Cobra.

omj

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Thanks for the feedback. Seems you may be the first person to try the ATS/Taurus combo and report back. I had a feeling one drawback would be increased pedal travel.

I wish I had a stock Cobra to compare with back to back. I'm not sure how much worse it actually is since I didn't pay much attention to the pedal feel before we started talking about it on here. It can't be too bad though if it is barely worse than my F350 and about same as my daily.
 

omj

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Thanks for the feedback. Seems you may be the first person to try the ATS/Taurus combo and report back. I had a feeling one drawback would be increased pedal travel.

I wish I had a stock Cobra to compare with back to back. I'm not sure how much worse it actually is since I didn't pay much attention to the pedal feel before we started talking about it on here. It can't be too bad though if it is barely worse than my F350 and about same as my daily.
 

bird_dog0347

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I will plan to do a few spirited braking runs before swapping mine to try to report on the difference... right now my pedal is pretty firm and doesn't travel much, so I'm sure this will change quite a bit but I was going to swap the master before this upgrade became a thing but now hopefully this makes it right where I want it. Either way, I'll report back once I have the bushings and can do the install.
 

cj428mach

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I was reading on another forum about the ATS calipers and the bias issue it causes. This was posted.

Baer offers an "upgrade" for the '94-04s to go to 13.25" rear rotors with the stock calipers. Working through the math and making some assumptions about effective rotor diameters, I get:
  • With 13" rotors and PBRs up front (with 38mm pistons), installing the 13.25" rear rotors would shift bias ~14% to the rear. I believe I've seen these larger rear rotors brought up in threads in the past, and it has been pointed out that installing them with stock fronts is not a performance upgrade.
  • With 13" rotors and Caddy Brembos up front (with 42mm pistons) + stock Cobra rears (11.65" rotors, 38mm Vargas), the bias would be shifted ~22% to the front (compared to 13"/38mm PBRs + 11.65"/38mm Vargas), as Jack has said before.
  • With 13" rotors and Caddy Brembos up front (with 42mm pistons) + Baer 13.25" rear rotors (with stock 38mm calipers), the bias would be shifted ~5.5% to the front (compared to 13"/38mm PBRs + 11.65"/38mm Vargas). Significantly better than with stock size rear rotors.
  • With 13" rotors and Caddy Brembos up front (with 42mm pistons) + 42mm Varga rear calipers on 11.65" Cobra rear rotors, the bias would be essentially the same as a stock Cobra setup.
Ok so the stock caliper on a 13" rotor on the rear improves the bias without the extra volume to maybe cause master cylinder issues. This seems like something worth pursuing.
Baer sells rotors separately so the issues will be

1. will a gt based rotor fit an irs hub?
2. What will it take to position the caliper in the correct location on the irs?

Rotors are going to be under $150 so if we can get a caliper bracket made it might not take much to do this. Any thoughts?
 

wckdvnm

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I was reading on another forum about the ATS calipers and the bias issue it causes. This was posted.

Baer offers an "upgrade" for the '94-04s to go to 13.25" rear rotors with the stock calipers. Working through the math and making some assumptions about effective rotor diameters, I get:
  • With 13" rotors and PBRs up front (with 38mm pistons), installing the 13.25" rear rotors would shift bias ~14% to the rear. I believe I've seen these larger rear rotors brought up in threads in the past, and it has been pointed out that installing them with stock fronts is not a performance upgrade.
  • With 13" rotors and Caddy Brembos up front (with 42mm pistons) + stock Cobra rears (11.65" rotors, 38mm Vargas), the bias would be shifted ~22% to the front (compared to 13"/38mm PBRs + 11.65"/38mm Vargas), as Jack has said before.
  • With 13" rotors and Caddy Brembos up front (with 42mm pistons) + Baer 13.25" rear rotors (with stock 38mm calipers), the bias would be shifted ~5.5% to the front (compared to 13"/38mm PBRs + 11.65"/38mm Vargas). Significantly better than with stock size rear rotors.
  • With 13" rotors and Caddy Brembos up front (with 42mm pistons) + 42mm Varga rear calipers on 11.65" Cobra rear rotors, the bias would be essentially the same as a stock Cobra setup.
Ok so the stock caliper on a 13" rotor on the rear improves the bias without the extra volume to maybe cause master cylinder issues. This seems like something worth pursuing.
Baer sells rotors separately so the issues will be

1. will a gt based rotor fit an irs hub?
2. What will it take to position the caliper in the correct location on the irs?

Rotors are going to be under $150 so if we can get a caliper bracket made it might not take much to do this. Any thoughts?

FTBR makes a 13” rotor conversion for the IRS cobras. Granted it uses his rotors but that is a kit that does work for the IRS cars.
 

cj428mach

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FTBR makes a 13” rotor conversion for the IRS cobras. Granted it uses his rotors but that is a kit that does work for the IRS cars.

Yeah I've seen that, but it's expensive and not really the look I'm going for on the rotor. Baer rotor appears to be available plain like stock at around $70 a piece.

I compared the specs on the Baer rotor and it looks like it would just drop on and not require moving the caliper forward or backward. The caliper would only need to raise straight out which should make fabricating a caliper relocation bracket much easier.
 

Blkkbgt

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I was reading on another forum about the ATS calipers and the bias issue it causes. This was posted.

Baer offers an "upgrade" for the '94-04s to go to 13.25" rear rotors with the stock calipers. Working through the math and making some assumptions about effective rotor diameters, I get:
  • With 13" rotors and PBRs up front (with 38mm pistons), installing the 13.25" rear rotors would shift bias ~14% to the rear. I believe I've seen these larger rear rotors brought up in threads in the past, and it has been pointed out that installing them with stock fronts is not a performance upgrade.
  • With 13" rotors and Caddy Brembos up front (with 42mm pistons) + stock Cobra rears (11.65" rotors, 38mm Vargas), the bias would be shifted ~22% to the front (compared to 13"/38mm PBRs + 11.65"/38mm Vargas), as Jack has said before.
  • With 13" rotors and Caddy Brembos up front (with 42mm pistons) + Baer 13.25" rear rotors (with stock 38mm calipers), the bias would be shifted ~5.5% to the front (compared to 13"/38mm PBRs + 11.65"/38mm Vargas). Significantly better than with stock size rear rotors.
  • With 13" rotors and Caddy Brembos up front (with 42mm pistons) + 42mm Varga rear calipers on 11.65" Cobra rear rotors, the bias would be essentially the same as a stock Cobra setup.
Ok so the stock caliper on a 13" rotor on the rear improves the bias without the extra volume to maybe cause master cylinder issues. This seems like something worth pursuing.
Baer sells rotors separately so the issues will be

1. will a gt based rotor fit an irs hub?
2. What will it take to position the caliper in the correct location on the irs?

Rotors are going to be under $150 so if we can get a caliper bracket made it might not take much to do this. Any thoughts?

This is all really good info.

I can tell you that a GT based rotor will fit an IRS hub. GT rotors have the same hat height or offset and are simply smaller diameter and thinner. I know this because I swapped larger rotors onto my old stick axle and instead of using relocation brackets I changed the anchor plates. The plates are just larger and have no additional offset.

One thing I don't like about the larger rotor option is the what if scenario down the line. I am talking about what if the rotors are discontinued or baer for some reason goes under? This could leave people in a bind down the road. Now if that rear rotor is actually a reproduction of an OEM rotor all that goes out the window and that would be and excellent solution.

As far as the master cylinder is concerned I am really curious as to whether or not we have a cheap 1-1/8 bore option. If we do it's actually a pretty cost effective solution in itself and it wouldn't be all that much more work if you do everything at once.
 

cj428mach

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This is all really good info.

I can tell you that a GT based rotor will fit an IRS hub. GT rotors have the same hat height or offset and are simply smaller diameter and thinner. I know this because I swapped larger rotors onto my old stick axle and instead of using relocation brackets I changed the anchor plates. The plates are just larger and have no additional offset.

One thing I don't like about the larger rotor option is the what if scenario down the line. I am talking about what if the rotors are discontinued or baer for some reason goes under? This could leave people in a bind down the road. Now if that rear rotor is actually a reproduction of an OEM rotor all that goes out the window and that would be and excellent solution.

As far as the master cylinder is concerned I am really curious as to whether or not we have a cheap 1-1/8 bore option. If we do it's actually a pretty cost effective solution in itself and it wouldn't be all that much more work if you do everything at once.


One thing about a different master cylinder is will it have a spot for a sensor in the reservoir?
 

4sdvenom

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That I am not sure of but I assumed that the reservoir would need to be swapped over based on the picture I saw. Would this work? Maybe.
The link that was posted earlier with all the different master cylinders, had a Ford 1 1/8" hydro-boost master cylinder listed! So it's either an upgrade or there is a Ford vehicle out there that uses it from the factory! Maybe the 05-06 Ford GT or the bigger Ford Trucks! I would definitely be tracking that down to see what's up with it. I believe it was listed for under $200 but if you could find an oem Ford vehicle that uses it one could find it in a junkyard to play around with.
Just thinking out loud here!
Ken
 

Blkkbgt

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The link that was posted earlier with all the different master cylinders, had a Ford 1 1/8" hydro-boost master cylinder listed! So it's either an upgrade or there is a Ford vehicle out there that uses it from the factory! Maybe the 05-06 Ford GT or the bigger Ford Trucks! I would definitely be tracking that down to see what's up with it. I believe it was listed for under $200 but if you could find an oem Ford vehicle that uses it one could find it in a junkyard to play around with.
Just thinking out loud here!
Ken

I know, that's the MC I was referring to. I have been trying to figure out which vehicle it belongs to via rock auto and haven't figured it out yet. Going strictly off the picture it doesn't have the MC fluid level senor in it and the reservoir is larger without the forward tilt that we have. Going strictly off the looks I believe we could swap our reservoirs over to larger MC but I have no way of verifying it unless I buy one.
 

KBR

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If I knew this would work I'd order it today?
I have all the other parts ready to go...ATS calipers front and Taurus rear, slotted rotors, stainless lines,...etc.

Ford 1-1/8 Inch Hydroboost Master Cylinder (with Cruise Control)

ford-1-1-8-inch-hydroboost-master-cylinder-with-cruise-control-3.jpg


Ford 1-1/8 Inch Hydroboost Master Cylinder (with Cruise Control)

Here's ours:
51pHSmLpgsL._AC_.jpg
 
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cj428mach

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Lines are on the wrong side. Maybe it has bleeders on the other side and they could be swapped. Seems like a big hassle unless the master cylinder was truly plugnplay. You also have to worry about hydroboost pushrod length too.

Now I was wondering if a person could find a shop to machine a stock cobra master cylinder for a larger piston. It's not uncommon to machine master cylinders for new sleeves.
 

cj428mach

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This is all really good info.

I can tell you that a GT based rotor will fit an IRS hub. GT rotors have the same hat height or offset and are simply smaller diameter and thinner. I know this because I swapped larger rotors onto my old stick axle and instead of using relocation brackets I changed the anchor plates. The plates are just larger and have no additional offset.

So if I'm understanding you correctly you re saying we could use sra rear caliper mounting brackets and they 'll bolt to the irs axle? If so then the Baer kit would be a bolt on and go? This seems like the easiest solution. The Baer kit with plain rotors is $235 so for around $300 I could have a 13inch bolt on rear setup.
 

KBR

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Lines are on the wrong side. Maybe it has bleeders on the other side and they could be swapped. Seems like a big hassle unless the master cylinder was truly plugnplay. You also have to worry about hydroboost pushrod length too.

Now I was wondering if a person could find a shop to machine a stock cobra master cylinder for a larger piston. It's not uncommon to machine master cylinders for new sleeves.

re; master cylinder, early morning = I didn't even realize the lines on the wrong side...I did email them.
 

Blkkbgt

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So if I'm understanding you correctly you re saying we could use sra rear caliper mounting brackets and they 'll bolt to the irs axle? If so then the Baer kit would be a bolt on and go? This seems like the easiest solution. The Baer kit with plain rotors is $235 so for around $300 I could have a 13inch bolt on rear setup.

Kind of but I am not 100% sure. I was more trying to explain that the rotors are basically the same minus the difference in diameter.

Now the brackets should bolt up but I could be missing something.
 

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