posted on December 07, 2011 00:00
Project Civic EJ: Fast Brakes Rear Disc Brake Conversion Kit
By Chuck Johnson
Photos by Joe Lu
After completing the install of the front Fast Brakes big brake kit, we knew that we had to do something about the drum brake lameness that was taking place on the rear of Project Civic. Project Civic had been retired to commuter car only status almost a decade ago and since then had only the basic maintenance performed. We were pretty suspicious that the rear drums weren't contributing any work in the whole braking equation since there seemed to be an abnormal amount of front brake bias. Never mind that the rear drums and shoes had not been replaced ever even after 260,000 miles of use.
After pulling off the drums, it was pretty obvious that the rear brakes had checked out and gone on vacation over a hundred or so thousand miles ago. (Speaking of vacations, I could sure use one right now.) There was plenty of friction material left on the shoes, perhaps caused from poor adjustment or a frozen brake cylinder. Who really cares, though?
Honestly, drum brakes suck in almost every way. Well, except for trapping heat and creating a crappy pedal feel as they distort and grow under compressive and thermal loads. They're pretty efficient at that stuff. Unlike disc brakes, drum brake's friction surfaces are encased in a cast iron "shell." This shell makes expelling heat a real challenge, causing heat to build up inside the drum. Also, the force of the drum brake's shoe is not opposed by an equal and opposite force like on a disc brake. On a disc brake system, the pads are essentially squeezing against one another with the rotor in the middle. Why is this important? Without equal forces acting on each side of the drum, we are left to rely on the stiffness of the drum's cast iron material to resist the compressive load of the shoe that's pushing against it. Ultimately, the drum itself gives way and distorts elastically under this load causing poor brake feel and performance. I'm sure there are applications where drums might be preferred but again, they're drum brakes and who really cares? I don't. Honestly, I wouldn't mind seeing them follow the dodo bird and the carburetor down the path of extinction.
So, instead of diagnosing the problem with Project Civic's rear suck brakes, we quickly removed Project Civic's drum brake assembly and pawned them off to the first scrap metal guy who drove by the MotoIQ garage. Our original thought was to replace Project Civic's drum brakes with the rear disc brakes from a Civic Si, but there's only one thing that we can't stand more than crappy, knock off parts and that's crappy, stolen parts. Stolen parts are just bad karma, so instead of risking getting a frozen pair of freshly stolen Civic Si calipers and seven years of bad luck, we opted for another one of Fast Brakes' big brake kits. This time though, the Fast Brakes kit was not only a big brake kit, but also a drum to disc brake conversion kit.
Wednesday, December 07, 2011 2:22 AM
Ah yes, the ever prevalent Honda theft problem.
Too bad really. I too passed up many too-good-to-be-legit deals when I had a Honda. I don't even want to think about how many of those parts were most likely stolen.
MotoIQ: leave it to them to call it like it is.
Wednesday, December 07, 2011 8:33 AM
wow I've heard that the theft problem on the west coast was bad, via the honda-tech forums but I didn't realize it was that bad.
Wednesday, December 07, 2011 8:48 AM
Stolen Hondas are a problem everywhere. I met a guy at an autocross who's car was stolen from inside his garage. They unhooked the alarm (which was hidden under the cowl and an engine bay wire tuck, and featured GPS tracking and igniton kill), found the steering wheel (which was removed with a quick release) and then drove the car away. He only knows they drove it because he got a ticket a week later for blowing through a toll booth. This is in southern PA.
I hate drum brakes. I was working on my CRV's rear brakes and wanted to burn them. Disc brakes are a hundred times easier to work on and they stop better. I'm looking for a disc conversion swap to I can get rid of those god awful brakes. Surprisingly the CRV stops pretty well even with the rear drums. I'm sure huge front brakes and ABS help.
Wednesday, December 07, 2011 10:44 AM
My friend's Integra got stolen, he was able to track it with the gps tracker he installed and notify the cops. When the cops got to the house of the theives, their backyard was basically a chopshop.
Wednesday, December 07, 2011 11:34 AM
Good post! Does a rear brake drum to disk conversion typically require an adjustment of brake bias?
I'm seriously thinking of doing this on my Suburban.
Wednesday, December 07, 2011 11:43 AM
Is there a weight savings benefit as well?
Wednesday, December 07, 2011 11:49 AM
Unfortunately, I was a bit hasty in my efforts to rid ourselves of drum brakes. I had the same question on weight when I sat down to write the article but threw away the drums before I weighed them, sorry. If I had to guess, I don't think that there would be much of a decrease in weight as we traded a cast iron drum and the parts it encases for for a large cast iron rotor and caliper.
Wednesday, December 07, 2011 5:59 PM
Back in 05' my SE-R was stolen with no steering wheel and a kill switch. Still have the steering wheel and keys! If you own a Honda, It better be locked in a garage with a alarm if you want to keep it. 90's Civic and Integras pretty much top the list for most stolen vehicles for last 10 years plus I believe. And 90's Sentras fall into the top 10 also.
Hey Chuck, why does it look like the pads are only contacting about 50% of the brake rotor in that finished install picture? Is it suppose to be that way?
Wednesday, December 07, 2011 8:42 PM
Sr20freak, I can see how the picture is a bit deceiving but the outside of the pad is lined up with the outer perimeter of the rotor. The picture is a bit of an optical illusion... I actually had to go out and look at it to make sure that the pad was fully engaging, lol.
Wednesday, December 07, 2011 8:55 PM
Ignoring any proportioning valve function, a base Integra has about 4:1 front/rear brake proportioning. An ITR is about 3:1. So there's apparently room to play with balance on the platform. If you push the limit of rear brake work, you'll want a high-quality, consistently-performing adjustable proportioning valve to pull it back from being over the edge if necessary. The ITR also has only 260mm rear rotors, getting most of its torque increase from a larger caliper piston.
Wednesday, December 07, 2011 9:23 PM
Good day! This is my first comment on MotoIQ. I generally find the content rather excellent, but, as someone who has driven Hondas almost exclusively for a while (1998), I really dislike the hate on the rear drums in Civics for 2 reasons:
1. Civic rear drums, when maintained properly, are WAY better with a vital function: the parking brake. I owned a '93 Civic Si that had more rust than actual solid body, and I replaced everything in the brake system except the hard lines. That thing wouldn't even hold the car on a hill, no matter what I did. To contrast this, my '89 CRX has drums that will absolutely function flawlessly as parking brakes and as rotational motivators, which is something a consider essential in the NE where we actually get snow.
2. The rear disc brakes never have worked correctly for very long for me or anyone else I know (in person), not even with a Fastbrakes conversion (11" conversion front and back on an '87 CRX Si and some other cars). I've also found that in most cases, I prefer the pedal feel on Civics with properly adjusted drums.
Stock drums weigh less and have lower rotational inertia than the 11" rotors and disc conversion.
The stock rear calipers leave crappy rust bands on the face of the rotors because the pads are no where near close to sweeping the whole face of the rotor. (I know that isn't too important to many people.)
-I don't track any cars. I know that being able to swap out pads is extremely important for a vehicle that will see track days.
-I have proper disc over drums on the rear of my Legend Coupe, and I happen to think that this is the really "proper" way to do things.
I just mostly wanted to present a perspective from a long time Honda driver who actually appreciates the more qualities of drums. They aren't all bad, but they are certainly not ideal for many situations.
Thursday, December 08, 2011 4:21 AM
Speaking of proportioning valves and other related hydraulic parts; do you all see the need for experimenting with other various OEM Honda proportioning valves and/or different sized OEM master cylinders yet, if at all?
At first, my old Honda's brake upgrades (DA Integra with ITR brakes) made my pedal travel much farther and made heel-toe matching nearly impossible without locking up at least the RF tire. I had to remedy this by converting the car to non-ABS by running a different master cylinder, booster and proportioning valve. I eventually found a combination of OEM parts that worked well. Project Civic still has ABS, correct? I didn't see anything about removing it and I'm pretty sure I still see ABS sensor wires. The DA Integra's ABS system is shit so most of them have gone bad and get removed by enthusiasts. Any plans to remove the ABS from this car? The options for brake boosters, master cylinders and proportioning valves opens a whole world of brake tuning on the cheap(er) when you ditch that large ugly box for a sleek, non-ABS proportioning valve nestled neatly away behind the shock tower.
Thursday, January 05, 2012 11:05 PM
Ah, gad I hate my life! Now I found out that fastbreaks have a perfect kit like this THAT I really want and just because I live i lovely Norway I can't get it. So I beg of you all, where can I get these kits that will shipp to me or dear MotoIq people can you pleas ask the nice people at fastbreaks to give me a break ^^
Monday, January 09, 2012 9:42 AM
@Ztaal3- Call Brian at Fastbrakes. I spoke with him last Friday and he said that he has one of these kits in stock and can ship to Norway.
Monday, January 09, 2012 4:57 PM
I figured a way around it, since I'm not the first to get stuff shipped to norway I used company that lives of it, Jetcarrier.com. so now I'm just waiting for him to machine up a set of mounting brakets for my primera/g20. just gotta find some breakpads and lines for the rear.
But THANK you verry much, Motoiq love is the best ^^
Thursday, December 13, 2012 12:37 PM
Something that worries me, how is the braking force of the front axle vs the rear axle affected by the conversion from drum to disc in the rear?
If now the rear axle will brake harder with the same brake pressure as before, then during hard braking the rear wheels are more likely to lock up with the front wheels still having a lot more force to go before breaking free. This does not make for a safe or effective braking situation.
Did you have to modify the hydraulic braking system to keep braking uniform?
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