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Has anyone added front calipers in the rear without upgrading to big brakes? If so any pros and cons? Any feedback is appreciated.
 

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Was wondering about this today as well. I would think that the brake bias would get thrown off amoung other complications.
 

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Was wondering about this today as well. I would think that the brake bias would get thrown off amoung other complications.
Correct.
You could do it, if you addressed the bias, but that is not overly trivial in an ABS'ed car.
 

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Yes, I have. The improvement in brake bias is wonderful. These cars don't have enough rear brake for aggressive driving. Prior to the mod, I found that the ABS would fire off anytime I got aggressive on the brakes due to the fronts trying to lock. I will say that the brake bias is not perfect (50/50) but is dam close. The weight bias in the car is approx. 35/65, front to rear(static), the previous brake bias was 65/35! I learned from years of racing how misunderstood rear brakes really are. You're slowing down, not just tire/wheel/rotors but also axles, differential, trans output, etc. To fine tune for street use, I use Hawk HPS pads in front and Hawk Ceramic pads in rear. The HPS pads have a bit more initial bite and makes for pretty good balance. I have yet to fire off the ABS since the mod. The next time I trip over some money I'm going to replace the rear calipers with AP's the have slightly smaller pistons (I think 38mm are available); that should put the balance pretty much dead on. Any more questions-feel free to pm me. I have had this mod for over two years now.
 

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Just remembered...cons-when mounting front calipers on the rear, you will need to check wheel clearance. My LSS wheels required 3mm spacers with longer bolts to clear the calipers. My Cup wheels do not require spacers. The curve of the backside of the LSS spokes doesn't quite clear. That would sum up the cons.
 

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Yes, I have. The improvement in brake bias is wonderful. These cars don't have enough rear brake for aggressive driving. Prior to the mod, I found that the ABS would fire off anytime I got aggressive on the brakes due to the fronts trying to lock. I will say that the brake bias is not perfect (50/50) but is dam close. The weight bias in the car is approx. 35/65, front to rear(static), the previous brake bias was 65/35! I learned from years of racing how misunderstood rear brakes really are. You're slowing down, not just tire/wheel/rotors but also axles, differential, trans output, etc. To fine tune for street use, I use Hawk HPS pads in front and Hawk Ceramic pads in rear. The HPS pads have a bit more initial bite and makes for pretty good balance. I have yet to fire off the ABS since the mod. The next time I trip over some money I'm going to replace the rear calipers with AP's the have slightly smaller pistons (I think 38mm are available); that should put the balance pretty much dead on. Any more questions-feel free to pm me. I have had this mod for over two years now.

So to put it another way, what you are saying is that swapping in bigger calipers in the rear actually helped with braking because the rear is in need of additional bias. Did you have to mess with any bias valves or did you just swap in calipers?
 

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No additional mod is necessary with the caliper install. The difference in piston sizes, as compared to the stock caliper, is what changes the brake bias. There are no negative effects on the ABS operation. I drive my car every day and I must say the brake performance is greatly improved.
 

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Per request-photos... IMG_1032.JPG

IMG_1033.JPG

IMG_1034.JPG
 

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As far as calipers with alternate size pistons, you'll need to find an AP dealer in the U.S. Eliseparts in the U.K. shows a 36mm AP option but, I found AP part numbers CP5316 and CP5317 are 38 and 41 respectively.
Cup wheels clear without spacers, LSS require 3mm spacers(and longer bolts).
 

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Yes, the original caliper is your park brake. The existing hydraulic line screws right in to the new caliper-you just reroute it, obviously. I found two used font calipers(with attaching bolts) and rotors on LT. I think I got them from Yoram(Keinayo). The brackets came from Sector 111. The pad swept area is larger on the front brakes, so you either need to resurface the old rear rotors or obtain fronts or just buy two new rotors.
 
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