2005 mustang gt gt500 calipers front tire clearance

[theRedStorm]

I currently have 20x8.5 on the front. Performance pack replicas. The calipers don't clear unfortunately. Any recommendations?
I was thinking a quarter inch hubcentic spacer should do the trick.
So I have 35 mm offset wheels.
2007 Shelby gt500 has +45mm offset wheels.
I'm assuming a 10mm spacer will fix this?

 

[AHaze]

You'll need to install longer wheel studs if you go that route. I could only get a 3mm spacer up front while retaining safe thread engagement.

 

[theRedStorm]

Yea im getting ARP studs. My only concern if the spacers are dangerous. I can't find a straightforward answer. I have hubcentic ones that do NOT have new bolts.

 

[AHaze]

Lots of folks (including me) are using a spacer up front on these cars without losing wheels. With an effective offset of +29, your scrub radius is gonna be pretty far off of where Ford designed it though. I don't know how big a deal that is.
Are you doing the brake upgrade with plans to track the car? If so, you will likely want to ditch the staggered 20s anyway.

 

[RED09GT]

If they are 20x8.5's they must be replicas rather than actual performance pack wheels.
If you have enough thread engagement, you will be fine with a spacer.

 

[theRedStorm]

If they are 20x8.5's they must be replicas rather than actual performance pack wheels.
If you have enough thread engagement, you will be fine with a spacer.

Yea they are the replicas. I love these wheel and I want to use them on a big brake kit. Would be a shame if I had to change wheels again

Lots of folks (including me) are using a spacer up front on these cars without losing wheels. With an effective offset of +29, your scrub radius is gonna be pretty far off of where Ford designed it though. I don't know how big a deal that is.
Are you doing the brake upgrade with plans to track the car? If so, you will likely want to ditch the staggered 20s anyway.

Not for track. Partially for looks. Also because I feel 2 pot brakes are outdated that I should upgrade lol. I've upgraded with a lot of power mods so I felt the brakes should also be done

Any real dangers of modifying scrub radius?

 

[RED09GT]

Any real dangers of modifying scrub radius?

It changes the feel if the steering slightly but not a significant amount. No dangers with that amount of change.

 

[DieHarder]

These lugs will provide the extended threads you need with the spacer. I have Brembo's on my car with a 10mm hub centric spacer and have experienced no issues whatsoever.

https://www.ebay.com/itm/20-LUG-NUT...JK-CJ-YJ-TJ-/131856991945?hash=item1eb34a06c9

 

[theRedStorm]

These lugs will provide the extended threads you need with the spacer. I have Brembo's on my car with a 10mm hub centric spacer and have experienced no issues whatsoever.
https://www.ebay.com/itm/20-LUG-NUT...JK-CJ-YJ-TJ-/131856991945?hash=item1eb34a06c9

Would I need 2 inch lug nuts for the arp studs or 1.5 inch would be enough?

 

[LarryJM]

I know the stock Base wheels for the 2014 need at least a 15mm spacer to clear. The ideal spacer would be 17mm. I have 20mms with 8.5mm clearance. I picked up some cheap Brembo wheels just in case.

 

[Norm Peterson]

Not for track. Partially for looks. Also because I feel 2 pot brakes are outdated that I should upgrade lol. I've upgraded with a lot of power mods so I felt the brakes should also be done

If you're not going to track the car (road course kind of track) or repeatedly make the car stop from high speeds, the 2-pot calipers are all you need pretty much regardless of how much power your engine is making.

What you could use is brake pads that have better initial bite and higher temperature capability, and better brake fluid. The only caveats are that track-rated pads will result in more dust and maybe some noise, but those are small prices to pay if you're going to drive in a manner that demands better braking.

FWIW, I used to run the little 12.4" 2-pot calipers on the road course, 20 minutes at a time or longer. Mid-level track pads, Motul RBF600 fluid, and some supplemental rotor cooling. That's way more than you'd get in any street driving, and more than you'd ever need for canyon running on those 20x8.5 wheels where you feel at all comfortable doing.

Any real dangers of modifying scrub radius?

My 11" wide front "track wheels" (plus a very thin spacer for each) have a resulting offset somewhere in the mid +30 range, and my -2° camber effectively makes the scrub radius a little bigger as well. Nothing unusual happens either on the street or at the track at g's well beyond anything you're likely to ever see in street driving.


Norm

 

[LarryJM]

If you're not going to track the car (road course kind of track) or repeatedly make the car stop from high speeds, the 2-pot calipers are all you need pretty much regardless of how much power your engine is making.

What you could use is brake pads that have better initial bite and higher temperature capability, and better brake fluid. The only caveats are that track-rated pads will result in more dust and maybe some noise, but those are small prices to pay if you're going to drive in a manner that demands better braking.

FWIW, I used to run the little 12.4" 2-pot calipers on the road course, 20 minutes at a time or longer. Mid-level track pads, Motul RBF600 fluid, and some supplemental rotor cooling. That's way more than you'd get in any street driving, and more than you'd ever need for canyon running on those 20x8.5 wheels where you feel at all comfortable doing.



My 11" wide front "track wheels" (plus a very thin spacer for each) have a resulting offset somewhere in the mid +30 range, and my -2° camber effectively makes the scrub radius a little bigger as well. Nothing unusual happens either on the street or at the track at g's well beyond anything you're likely to ever see in street driving.

.

I do not necessary agree with that. My Altima SR 3.5 was always a better stopper then my Mustang GT until I added big brakes. Both come in at 3450 lbs. You really notice it test driving the big three $70,000 machines.

 

[Norm Peterson]

View attachment 76077 I do not necessary agree with that. My Altima SR 3.5 was always a better stopper then my Mustang GT until I added big brakes. Both come in at 3450 lbs.

Unless you know more about the brake systems - and particularly the pads - for both cars, that's not a helpful comparison.

I've run a variety of pads on various cars, and there's a huge difference in stopping power between most OE and OE replacement pads and pads intended for autocross use or higher. Hawk's HPS pads are essentially OE replacement pads, having no better than OE-level 'bite' in recent years.

Guaranteed you'd be impressed with either Hawk's HP+, Carbotech's XP-8, or G-loc's R8 pads on the 12.4" brakes. The hot tip being XP-8 or R8, as they're not nearly as abrasive on your rotors as the Hawks are.

But you have to actually try them to know this for yourself. I can only tell you what to expect from my own direct experiences on track and on the street.

You really notice it test driving the big three $70,000 machines.

I'm curious . . . what "big three $70,000 machines" are you talking about?


Norm

 

[LarryJM]

Unless you know more about the brake systems - and particularly the pads - for both cars, that's not a helpful comparison.

I've run a variety of pads on various cars, and there's a huge difference in stopping power between most OE and OE replacement pads and pads intended for autocross use or higher. Hawk's HPS pads are essentially OE replacement pads, having no better than OE-level 'bite' in recent years.

Guaranteed you'd be impressed with either Hawk's HP+, Carbotech's XP-8, or G-loc's R8 pads on the 12.4" brakes. The hot tip being XP-8 or R8, as they're not nearly as abrasive on your rotors as the Hawks are.

But you have to actually try them to know this for yourself. I can only tell you what to expect from my own direct experiences on track and on the street.



I'm curious . . . what "big three $70,000 machines" are you talking about?


Norm

Camaro ZL-1, Hellcat and the GT500. Although I could not get a test drive in a GT500.

This whole business with brakes for the street can be almost like the Democrats against the Republicans. What is true and what is not. Then it is possible my back brakes in the GT were sticking for some time and I was really only using the fronts. Braking for me is 1/4 inch travel of the brake pedal and then you feel a slight drag. More pressure and your I-Phone flies off the seat onto the floor and up under the dash. After three tries, I am happy with the results. This is the first try. What I didn't like was the back brakes were now hot and they rusted like mad on the first wash.

 

[LarryJM]

Second try same rotor but fully zinc coated with new power stop calipers and Raybestos street pads. Then third try a brake bleed.

 

[Norm Peterson]

Camaro ZL-1, Hellcat and the GT500. Although I could not get a test drive in a GT500.

Thanks.

This whole business with brakes for the street can be almost like the Democrats against the Republicans. What is true and what is not.

Not if you're an engineer. Or if you were one.

One thing that's absolutely true as far as brake bite is concerned true is the coefficient of friction, which can vary from 0.40-0.45 for typical street pads, to 0.50-0.55 for entry level track pads, through 0.6-ish for mid-level track pads, up to more than 0.7 for truly serious track pads.

Just stepping up from 0.45 to 0.55 is going to give you more brake bite than going from 12.4" to 14" with the rotors and continuing to run street pads. Stepping past entry level pads to 0.6 pads beats even 12.4" to 15.5" at the rotor. Quickie math here only, as I didn't go looking for mean radius of the swept areas.

I can tell you that an 0.6 pad can practically stand the car on its nose without having to do much more than step on the brake pedal firmly. No stomping, no lifting your right heel off of the floor, just a hard-normal brake application is all it takes. With 12.4" brakes.


Norm

 

[LarryJM]

Third try

Thanks.



Not if you're an engineer. Or if you were one.

One thing that's absolutely true as far as brake bite is concerned true is the coefficient of friction, which can vary from 0.40-0.45 for typical street pads, to 0.50-0.55 for entry level track pads, through 0.6-ish for mid-level track pads, up to more than 0.7 for truly serious track pads.

Just stepping up from 0.45 to 0.55 is going to give you more brake bite than going from 12.4" to 14" with the rotors and continuing to run street pads. Stepping past entry level pads to 0.6 pads beats even 12.4" to 15.5" at the rotor. Quickie math here only, as I didn't go looking for mean radius of the swept areas.

I can tell you that an 0.6 pad can practically stand the car on its nose without having to do much more than step on the brake pedal firmly. No stomping, no lifting your right heel off of the floor, just a hard-normal brake application is all it takes. With 12.4" brakes.


Norm

Yes but the GT500 brakes look so much better.

 

[Norm Peterson]

Third try


Yes but the GT500 brakes look so much better.

True, but even those will provide more stopping power from a given amount of pedal pressure if you load the calipers up with higher-friction (higher-mu) pads. Max braking would be about the same, but you wouldn't be working as hard to get there.

I'm currently running the 14" SVT/Brembo front brakes with R10 G-locs.


Norm

 

[DieHarder]

I changed over to the 4 pot Brembo's in 2019. Got them from O'Reilly's but haven't checked if they're legit or knockoffs. Spent ~ $230 for both if i remember correctly. Came in gloss black and didn't need any touch up. Bought some decent (mid-level pads), slapped some stickers on and installed them. Brake effort is noticeably less and seat of the pants stopping distance shortened a fair bit (at least it feels like it and one panic stop actually surprised me; didn't think I was going to be able to avoid someone who stopped short).

I did have to install a 10mm hubcentric spacer and I opted to use extended thread lug nuts which allowed me to retain the stock wheel studs. No difference noted with handling. (Note: ET lugs may not work in all applications but I had no problems using stock wheels).

https://www.ebay.com/itm/20-LUG-NUT...e=STRK:MEBIDX:IT&_trksid=p2060353.m1438.l2649

Currently working on finding aftermarket wheels that don't require spacers but not in that much of a hurry.

 

[LarryJM]

Brembo wheels are all over the place for cost. From $50 each on Craigslist to $500 each at some fancy wheel place. I have seen wheels in a junkyard in the mud that they want $250 each to $100 each for wheels still on the car. You really deal with a lot of low lifes cruising junkyards for wheels.