I've been pondering ideas about what brakes to use on a traditional T speedster build, when I saw this on Espay- okay, I know that's the BEST place to find inspiration... But seriously, how safe would this be for a lightweight car?
Sorry, I'm speicifically asking about the brake setup- I will be using a different rear (not sure which yet, but NOT a T rear).
the only place that makes any sense at all is on a T rear where you may not be able to use anything but the stock T brakes otherwise it is just a super duper parking brake and you still need brakes to stop the car with that set up you are trying to stop the motor. that's just weird
Personally, i wouldn't trust just a pinion brake even on a light weight car.. I picture rear end carnage if you had to panic stop.....the drive shaft would stop rotating, but the rest of the rear end would still want to turn..... If possible, i'd stick with some early juice brake's..traditional, would fit the build of a T speedster and would stop it at the axles.. Just my opinion of course.. Tony
I know this may sound crazy but on duece-and-a-half military and other trucks the only braking is pinion braking. They are stopping a crazy amount of weight. Also have you ever moved a vehicle by grabbing and turning the driveshaft? It really doesn't take much to move them due to gear ratios so the same with the braking. It doesn't take a m***ive rotor to stop a 3000# car. The only concern I would have is axle shaft strength and tires on different road surfaces (...dirt under one wheel and asphalt under the other). This could be a problem with an open differential as both axle shafts are independent from each other which means the effective braking is cut in half. Now with a spooled rearend this would not be a problem. ******Knuckles
Absolutely not!! Just think of the multiplication of torque to the driveshaft due to the ratio of the differential!! And then half the braking power with one brake instead of two!! Those things barely work as a parking brake. VERY SCAREY!!! Actually your front brakes are the most important because they are responsible for 70% of your braking power but I would use a rear end with decent drum brakes, I think your life is worth it!
How many cars have you seen that came off the ***y. line in Detroit with a pinion only brake? Do you think there might be a reason for that?
A stock model T only had one brake...in the transmission. If you were ever going up or down a hill and heard a "BANG" you were suppost to immedietly drive it into a ditch to stop it, because more than likley that noise you heard was the transmission...meaning no brakes! Cars have come a long ways since then, and for good reason
I don't think you would have a problem with it on a T speedster with a T engine and narrow tires. As Chris said the original T brakes are in the trans. That's what the third pedal is for. We are talking about stopping a 1200 lb car with probably 50 hp with 3 inch wide back tires. No I wouldn't suggest it for a V8 powered hotrod with ten inch wide tires and 300 hp. Mac, I've got a friend in Florida who's family (grandad, mom and him) are seriously into T speedsters. I'll run that past him and see what he says but I would bet he still runs the brake in the trans.
Going on the sides of a independent rear axle is on thing, THAT on the other hand is dangerous especially in an automatic where you cant clutch. In automatics while the engine spools down your still putting power to that driveshaft. you'll be lucky if the shaft only beats the bottom of the car up after it breaks. it could come up and say hi, and shave some body parts from you for once. lol
hey mac would you be using this as your only form of braking on the rear then i would not go for it but its ok for a parking brake as its fitted to early landrovers and rangerovers as standard but a word of warning i have a friend that had a prop brake fitted to his pro street car and when it went for the M.O.T they applied the brake whilst it was on the brake test machine and totally recked the trans (th350)
I can see what you're trying to do, but that is one experiment best left alone. A car needs good brakes on all four corners. Your cornering, for one, is controled a bit by braking in the front. You'd lose that with this setup. I don't think you'll be happy with that setup from a driving or safety point of view. Makes a nice parking brake, though.
Not saying it's a good idea for a street driven car but ever watch the Monster Jam on speed ch. Those trucks weigh 10,000 lbs. and have over 1,000 hp. and have Huge tires, take some serious abuse. Yeah they have four wheel drive with front and rear brakes but most that I've seen use the set up on the driveshaft.
no, not a good idea. you would be better off cutting a hole in the floor and using your feet to stop.
The trouble with driveshaft pincher brakes is, when you really jump on them, the driveshaft stops turning, and the wheel with good traction keeps turning, which makes the other wheel turn backwards. Not conducive to good handling! Most farm trucks have E-brakes like that, very interesting to stop sometimes.
Hmmm... the regular brakes at the end of axles just stop the motor as well... weird... wow... and the brakes on a Jag rear only half stop the motor and half the car... even weirder... This has been done before, it would work on a very light car... but there are downsides to it...
I would run it on a open diff car but only if I had some stout front brakes. You have to remember how much less braking the rear wheels do than the fronts. For an occasional driver not meant to see adverse weather I would run it in most applications.
When I was a teenager back in the 50s we would all use the parking brakes when we saw the cops so they wouldn't see the brakelights come on as we slowed before they could get close enough to clock us (no radar back then). But this was Fords and Chevys, etc. with parking brakes mechanically actuating the rear brake shoes. My cousin's Mom had a Nash and he tried that. Problem was the parking brake was a drum on the pinion yoke. It broke the U-joints, bent the driveshaft, and beat the Hell out of the bottom of the floor pan! Dave
Agreed!!! Thats it's design and intent. IMO, Using it as a pedal brake would make the rear end and the rear suspension act a little goofy when you do a moderate speed stop.
Thanks for all the input, guys! Yeah, I thought it was kinda hinky, too- just wanted to run it up the flag pole to see if anyone saluted! Mr48Chev, if you do get ahold of your friend, could you ask him what he recommends for brakes? The car will most likely not have fenders (or will use bicycle-type fenders if needed), but will be using '25-'30 Chevy disk wheels, so I'm looking for a period look, at least. Also, it will have a modern drivetrain (Quad4/T5), so any recommendations on a capable rear are appreciated as well!
I would ask how big is the rotor and how many pistons ore in the caliper? If its rated for such a load and you have the clearance, it shouldn't be a problem. And yes the military has great success with the set up.
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