Brakes The Ultimate 4-lug/5-lug Brake Conversion/upgrade Thread
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You can, but only with SVO rear brakes.
Those axles are 1.25" longer than drum brake axles, so they stick way out. The only brake setup that works with them is the 84-86SVO and 84-90 Mark 7 rear disks
Boricua86
Active Member
So let me run this by you guys, I have completed the 5 lug swap and used the following brake set up
Front:
SN95 spindles (1995)
Cadillac ATS Brembo calipers
13" rotors
Power Stop pads
Rear:
Fox length axles
SN95 calipers (1995)
Power Stop pads
Under Hood:
SN95 booster (1995)
SN95 MC (1995)
Wilwood Prop valve
Am I missing anything?
and
Would the booster and MC be enough to run the set up?
Thanks in advance folks.
Front:
SN95 spindles (1995)
Cadillac ATS Brembo calipers
13" rotors
Power Stop pads
Rear:
Fox length axles
SN95 calipers (1995)
Power Stop pads
Under Hood:
SN95 booster (1995)
SN95 MC (1995)
Wilwood Prop valve
Am I missing anything?
and
Would the booster and MC be enough to run the set up?
Thanks in advance folks.
What's the bore on the MC. You may need something bigger than a stock 95 MC.
A stock '01 GT that has dual piston PBR calipers (dual 45mm pistons) which gives them a 6361 square mm of piston area on the front. Your set up is quad 42mm pistons per side, that's 11080 square mm for the front. I think your MC won't be able to move enough fluid to be effective. I believe the stock '01 has a 1-1/16" bore MC. If so, you will likely need a larger one than that.
Set up looks impressive. Did you fabricate mounting brackets for the calipers? If so, any pics?
A stock '01 GT that has dual piston PBR calipers (dual 45mm pistons) which gives them a 6361 square mm of piston area on the front. Your set up is quad 42mm pistons per side, that's 11080 square mm for the front. I think your MC won't be able to move enough fluid to be effective. I believe the stock '01 has a 1-1/16" bore MC. If so, you will likely need a larger one than that.
Set up looks impressive. Did you fabricate mounting brackets for the calipers? If so, any pics?
With opposing piston calipers, you only need to process two of the 4 pistons in that calculation.
A 1" bore MC (1993 Cobra) should be adequate for the ATS front and 38mm rear calipers
A 1 1/16" MX (94-95GT) should be adequate for the ATS front and 43mm Taurus rear calipers (better brake balance)
The hydroboost uses 1 1/16, but the V6 with vacuum assist uses a 1.003" bore MC with the dual 45mm fronts.
A 1" bore MC (1993 Cobra) should be adequate for the ATS front and 38mm rear calipers
A 1 1/16" MX (94-95GT) should be adequate for the ATS front and 43mm Taurus rear calipers (better brake balance)
The hydroboost uses 1 1/16, but the V6 with vacuum assist uses a 1.003" bore MC with the dual 45mm fronts.
Boricua86
Active Member
I cant take credit for the idea. There is a write here and at the corral about these brakes. there two ways to do it, get the prefab inserts that will move the caliper into place, or enlarge the holes on the spindles (caliper mounts)….
either way thanks,
Boricua86
Active Member
WHat booster?
If stock booster, go 93 cobra. If SN95 or 93 cobra booster, the 94-95 GT 1 1/16" MC might be a better choice
When I did my napkin calcs, the setup that seemed most ideal on paper was ATS front/43mm rear calipers, with 1 1/16" MC giving you around a 73/27% brake bias split.
When I get to installing this on my car, the above is what I plan on doing.
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Boricua86
Active Member
I enlarged the holes. Well enlarged one, and "elongated" the other by a bit. My signature pic is the final product. Just working on under the hood stuff
Boricua86
Active Member
Boricua86
Active Member
Hey what's the brake bias with the 95 GT booster and MC?
Also, I've always wanted to learn the formula for the brake bias... where could I find it?
Boricua86
Active Member
Bias has nothing to do with the booster/MC.
It's a calculation based on caliper piston sizes, pad area, and rotor sizes. It gets to be a bit complex. Number of online resources to calc it out.
Somewhat 5 lug swap related:
Anyone have experience with a 5 lug swap using SN95 axles and wheels that are 17x8.5” with 30mm offset (5.9 bs)?
My plans are to use 98 cobra wheels, but the repro 93 Cobras from LMR keep catching my eye - I just think with SN95 axles it’ll be close (Nitto 245/45/17 tires, stock rear 89 LX springs)
EDIT: decided to do the math myself.
The old FRPP wheels that fit with SN95 axles measure 17x9” with 36mm offset.
The replica 93 Cobras are 17x8.5”, with 30mm offset.
The difference in width is roughly accounted for by the difference in offset (centerline is 4.5” vs 4.25”; 6mm offset is roughly 0.25”).
So it looks like it would work, assuming the 17x9” w/36mm offset fits. That said, ‘98 Cobras will actually have a bit more fender room. It’ll also fit my Brembos I’ll be mounting later on down the road.
Anyone have experience with a 5 lug swap using SN95 axles and wheels that are 17x8.5” with 30mm offset (5.9 bs)?
My plans are to use 98 cobra wheels, but the repro 93 Cobras from LMR keep catching my eye - I just think with SN95 axles it’ll be close (Nitto 245/45/17 tires, stock rear 89 LX springs)
EDIT: decided to do the math myself.
The old FRPP wheels that fit with SN95 axles measure 17x9” with 36mm offset.
The replica 93 Cobras are 17x8.5”, with 30mm offset.
The difference in width is roughly accounted for by the difference in offset (centerline is 4.5” vs 4.25”; 6mm offset is roughly 0.25”).
So it looks like it would work, assuming the 17x9” w/36mm offset fits. That said, ‘98 Cobras will actually have a bit more fender room. It’ll also fit my Brembos I’ll be mounting later on down the road.
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89gt89
Member
I'd like to see how they fit w/sn95 length rear axles as well. Does one need to roll the fender?
89gt89
Member
I just got my order today from LMR for a 5 lug 93 Cobra wheel. It'll fit perfect with the following SN95 combo: 94 - 98 stock length axles tucked into a 88 Turbo Coupe 8.8 housing riding on eibach Sportline springs. There's about 1/8 - 1/4 between the lip of the rim and the outside of your rear wheel body lip. I have an MM torque arm and panhard so I'm perfectly centered. You might need a "soft" roll on your fender. Not a flush roll. The TC 8.8 quad shock mounts(slightly different geometry than mustang) make it impossible for me to run a quad (if I weren't already running the torque arm). I'll post a video to youtube type 89gt89 showing them on my 93 Cobra w/big brake upgrade guide. I'm glad I bought 1 wheel as a test before buying stock length fox 5 lug axles, caliper mounting brackets, etc. On a side note. I originally did a fox length SN rear disc conversion on my 91 coupe. Funny thing is....I kept adding wheel spacers until I got the fit I wanted...ended up being 3/4 longer than stock...exactly the same as an SN axle length. One last thing worth mentioning. LMR says these wheels are not returnable. Hope this helps.
This is very helpful, thank you!
I ended up sticking to SN95axles/‘98 cobras, but if I ever decide to change it’s helpful to know.
Only difference is the brr54 is a service rotor, so it’s coated. The 198 is bare.
at keast that’s what it should be
at keast that’s what it should be
