front brake conversion to drum
#3
10-19-2011, 05:42 PM
If you're worried about the negligible drag inherent to the design of disc brakes, I'm assuming you've already got airflow completely figured out, dropped the final drive in your transmission to a numerically lower gear, and have the engine running as efficiently as possible. Is that correct?
Honestly, the drag from pads contacting rotors is one of the last concerns I'd have when building a car for hypermiling.
Honestly, the drag from pads contacting rotors is one of the last concerns I'd have when building a car for hypermiling.
#4
10-20-2011, 11:43 AM
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dito... at most replace the calipers with some brand new ones and new slide bolts and properly lube them well will be much better than drum brakes! and like said drums on front IS NOT FUN! my 66impala has drums all the way around and its brakes SUCK!!!!!!! well doesnt help the beast is american steel but still they suck compared to disc brakes!
the best you can do is just make sure the slides and pistons all move freely back and forth!
ive had more problems with sticking slide bolts and caliper pistons sticking than anything. but if you replace those you should be golden and still have great brakes!!!! DONT SWITCH TO DRUMS OR YOU WILL REGRET IT!!!!!!
the best you can do is just make sure the slides and pistons all move freely back and forth!
ive had more problems with sticking slide bolts and caliper pistons sticking than anything. but if you replace those you should be golden and still have great brakes!!!! DONT SWITCH TO DRUMS OR YOU WILL REGRET IT!!!!!!
#5
10-20-2011, 07:50 PM
^ Lol I drove my friends 67 (I think) Coronet, first time driving powerless and drum all around brakes. Def something I wasn't used to!
#6
12-10-2011, 03:55 PM
Another thing to consider with the swap is the cost. If the price of obtaining the parts and installing them is less than what you'll save in fuel, then it's worth it. If it'll cost more than the gas you predict you'll save, it's just doesn't make sense economically.
On a side note, I'd love to hear more about the 750cc conversion. What motor/trans did you source? Is it a Honda CB750, or did you go with a different bike motor?
On a side note, I'd love to hear more about the 750cc conversion. What motor/trans did you source? Is it a Honda CB750, or did you go with a different bike motor?
Last edited by ChristianL; 12-10-2011 at 03:57 PM.
#7
12-11-2011, 10:31 PM
Should I do it, it might set me back all of maybe $100 at most. It isn't about the cost, it is moreso on how much time is invested generating the conversion. It is really all about reducing rolling resistance. Most can not comprehend the issue. Brake drag goes along with disc brakes, whereas drum brakes, when set up correctly, may introduce no drag at all.
I am in the process of generating a patent on a rotor that can relieve the drag through increased thermal expansion, not to mention having much lower mass, moment of inertia and pound for pound, the highest thermal capacity.
Over a decade ago, I'd run our '87 CRX on the road, normally aspirated, on 2 cylinders. I've wanted to convert another Honda to run on the 2 outside cylinders, utilizing the 2 center cylinders for combined intake every stroke (welding & regrinding cam) to boost the running cylinders up to 14 psi. Then I may tack on a turbo. ...am fabricating my own custom jet plugs to prevent detonation and also piston melt (not the same thing).
I have 5 CRXs, an Integra, a pair of Civics (along with a ZC engine) to choose from as a lucky candidate. Wife won't let me even consider her Miata. Will be looking at another '87 CRX tomorrow.
This drum conversion is nothing compared to my 650 lb. Berkeley, 7 hp diesel-electric hybrid of three decades ago (drum brakes all around, too!).
I am in the process of generating a patent on a rotor that can relieve the drag through increased thermal expansion, not to mention having much lower mass, moment of inertia and pound for pound, the highest thermal capacity.
Over a decade ago, I'd run our '87 CRX on the road, normally aspirated, on 2 cylinders. I've wanted to convert another Honda to run on the 2 outside cylinders, utilizing the 2 center cylinders for combined intake every stroke (welding & regrinding cam) to boost the running cylinders up to 14 psi. Then I may tack on a turbo. ...am fabricating my own custom jet plugs to prevent detonation and also piston melt (not the same thing).
I have 5 CRXs, an Integra, a pair of Civics (along with a ZC engine) to choose from as a lucky candidate. Wife won't let me even consider her Miata. Will be looking at another '87 CRX tomorrow.
This drum conversion is nothing compared to my 650 lb. Berkeley, 7 hp diesel-electric hybrid of three decades ago (drum brakes all around, too!).
Last edited by jrnsr; 12-11-2011 at 10:55 PM.
#8
12-12-2011, 05:23 AM
Sounds VERY cool, and a great concept. I'd love to keep tabs on your progress during development.
Funny you bring up the Berkeley. Did you read the series in Grassroots Motorsports about their restoration/modification of one? Pretty cool stuff, but I'm not sure I'd want to drive it on anything but an autocross course.
Let me know if you want to start playing with the Miata. I've been driving and working on them for 15 years now, so I might have some info that'll help. Also, give a call to Keith Tanner at Flyin' Miata - he's an invaluable source of knowledge, and may have some insight into your engine building. His Locost 7 was a fun piece of engineering.
Overall, good fuel economy in a Miata has not been very successful due to the car's shape. However, some improvements can be made by modifying the rear bumper (which collects air like a parachute), and a friend of mine reports he consistently gets a 3mpg increase with his hardtop on.
Getting back to your original question, however, I'm wondering if you could source some parts from one of the all-wheel drive Civics from the '86-'87 vintage. I imagine the rear hubs might be able to be used in the front, and put you in the neighborhood of fitting an axle spline together, along with all the drum brake hardware. Maybe another way to go is on something like an AWD CR-V or Element.
Funny you bring up the Berkeley. Did you read the series in Grassroots Motorsports about their restoration/modification of one? Pretty cool stuff, but I'm not sure I'd want to drive it on anything but an autocross course.
Let me know if you want to start playing with the Miata. I've been driving and working on them for 15 years now, so I might have some info that'll help. Also, give a call to Keith Tanner at Flyin' Miata - he's an invaluable source of knowledge, and may have some insight into your engine building. His Locost 7 was a fun piece of engineering.
Overall, good fuel economy in a Miata has not been very successful due to the car's shape. However, some improvements can be made by modifying the rear bumper (which collects air like a parachute), and a friend of mine reports he consistently gets a 3mpg increase with his hardtop on.
Getting back to your original question, however, I'm wondering if you could source some parts from one of the all-wheel drive Civics from the '86-'87 vintage. I imagine the rear hubs might be able to be used in the front, and put you in the neighborhood of fitting an axle spline together, along with all the drum brake hardware. Maybe another way to go is on something like an AWD CR-V or Element.
