Does anybody have any idea why car makers still use drum brakes? With all of the advantages of disk brakes, and the ease of working on them why are they still using out-dated drums in the 21st Century. Shouldn't they be standard on all cars. How hard would it be to do this! Is it just a marketing thing or what.

 

I'd have to assume that they'd be easier to make, a few flat peices of metal, some springs, and a cast drum, nothing to them. And they last forever and are effective for daily drivers.

 

I don't get it either. I thought all WS6 cars had 4 wheel discs, but not mine. Now I have to do the conversion. Sux for me.

------------------
1990 Formula 350
*Hooker Headers
*Flowmaster 3" Exhaust(no cat)
*Accel AFPR
*K&N
*Airfoil
*170* Thermostat
*'99 16x8 Formula Wheels
*Metco Lower Control Arms

 

It's easier to fit a small rim over drums than it is over a caliper. If I didn't have rear disk brakes I could have gotten rims with a bit more backspace to stuff the tires further under the fenders.

------------------
Follow my racing progress on Stephen's racing page
and check out the race car

87 IROC-Z Pro ET Bracket Race Car
383 stroker (carbed) with double hump cast iron heads and pump gas
461 Big Block installed and ready for the 2001 racing season

Best results before the 383 blew up
Best ET on a time slip: 11.857 altitude corrected to 11.163
Best MPH on a time slip: 117.87 altitude corrected to 126.10
Altitude corrected rear wheel HP based on power to weight ratio: 476.5
Best 60 foot: 1.662

Racing at 3500 feet elevation but most race days it's over 5000 feet density altitude!
Member of the Calgary Drag Racing Association

87 IROC bracket car, 91 454SS daily driver, 95 Homebuilt Harley

 

$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$

All that car companies care about is the cheese.

Drum brakes are alot cheaper than disk. I think the calipers are the costy item. The average car buyer doesn't know or care what kind of brakes they have as long as they can stop. When GM makes a million cars a year, a few dollars saved per vehicle equals millions dollars saved in the long run.


------------------
87 IROC 350
Mods: 3:42 Torsen, pocket ported 083 heads, complete Edelbrock exhaust, Most free mods, Most little mods, aluminum d/s. Edelbrock STB, boxed rear suspension pieces, urethane bushings everywhere.
Stock cam, chip, runners, base, and trans
13.94@103mph, 2.25 60'
Recent stuff: SSM sfc's, Homemade relocation brackets, Ported SLP runners, ported base, EGR!
Current/future projects: homemade torque arm, and 27x10 Hoosiers (need wheels!), and Prom Burning
Planning new engine build, possibly 383 w/ TFS 23*

 

Also, from a racing standpoint...

1. Drum brakes weigh less than disc brakes
2. There's no "pad drag" with drums

Of course, the safety points outweigh the racing ones. Plus, pad drag is very minimal.


------------------
-Tom P (Hot rodded 1986 Firebird 2.8l) from http://www.f-body.net/mailbag/3rd/3rd_mailbag.html message boards
---Think your car could be pic of the week? Visit http://www.f-body.net for details!

 

GM did try to go with disc all the way around. They had a huge problem with e brake malfuctions, so they went back to drum until the fourth gens. As far as stopping, drum in the rear isn't all that bad. The only time most drivers actually really need it is with auto cross. I do think that they should be all disc though.

------------------

• 89 Formula 305 WS6
  SFC's,
  LCA's,
  Air foil
  Flowmaster cat back
  Tranny Cooler
  A/F Ratio Meter
  Trans Temp (not a mod but it sure spurs interest)
• 90 Eagle Talon 2.0
  (winter beater)
  Mods? HA! its a rice burner!

 

Originally posted by IrocStan:
Took the words right out of my mouth.
Adding on to this, all the economy cars [read: Hyundai, Honda Civic] have rear drums. Probably more than one reason why these cars are dirt cheap brand new
------------------
--Steve S--
1984 Trans Am 305 LG4, 5 speed
RPO codes point to Recaro version
Daily Driver, Flowmaster 80 Series

[This message has been edited by 84TransAm (edited February 06, 2001).]

 

Or option C or as I like to call it buy in bulk. I often wonder if GM bought a stockpile in the 70's planning for the future and have huge warehouses with just drum brakes and they're still trying to use up their supply. There hasn't been an modification to drum brake set-ups since the 70's........

Seriously I think that drum brakes are better for non-ABS cars, they don't seem as sensitive. I rebuilt the rear drums on the daily driver and it's still harder to lock up the rears than the fronts and it looks like the fronts are 17 yr old OEM pads.

------------------
1984 WS6 Trans Am Hartop
Former L69 Car under restoration
1984 Trans Am T-tops
4-bolt main 350, performer intake, headers, Holley 650, T-5, hayes clutch, dual elec. fans and 3.23's.
Daily driver and restoration
13.98 @ 101

 

The fronts should actually lock first since they are designed this way for safety "in the snow" driving. Adjustable propotioning valves are the best way to go IMO