in too deep: trying to go BBP on a 68 barracuda and its going.. poorly.

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Like our beloved high school auto shop teacher used to say "Braking is least effective during a skid".

Exactly!

This isn't all that hard to understand, and it's printed anywhere you might look. One might even say it's just a fact of basic physics, and common knowledge for anyone in the automotive field! Seems like a silly thing to be trying to argue against.

I grew up driving boats before cars. I time lights. I'm not stupid enough to ride someones backside. If someone drives like a moron, I get as far away from them as possible. I've probably put half a million miles on A Body Barraudas with 10 in drum brakes and never needed more. Shouldn't she be driving a red Super Stock Dodge?

While those are all good habits to have they do not guarantee that someone without good driving habits won't do something stupid and put you in a situation where you'd need better than 10" drums. Just takes one dipstick to cut you off and slam on the brakes, and if they're in something made in the last decade or two you've got no shot at stopping short with factory drums.

Sounds like you've been very fortunate for a very long time, which is great. But 10" brakes are not at all great by todays standards, and there are simple upgrades that can dramatically improve your stopping distances. Even just the factory disk brakes can improve stopping distances substantially, you don't need to go full pro touring to stop much better than you can with 10" drums all the way 'round. Now granted that will still put you at a disadvantage against a modern car, but if you knock a car length off your stopping distance that just might be a car you don't hit.
 
I can say this for drum brakes. If they are in good shape and adjusted properly, they can stop a car surprisingly well. But, since I've been driving Vixen for a long time now, I can feel them fade every now and then when I make a quick stop. You can feel the braking effect just get less and less. That's the brakes over heating. They're only 9" drums, so they weren't meant for autocross. 10" brakes would be better, I'm sure, but she's gettin discs next.
 
I can say this for drum brakes. If they are in good shape and adjusted properly, they can stop a car surprisingly well. But, since I've been driving Vixen for a long time now, I can feel them fade every now and then when I make a quick stop. You can feel the braking effect just get less and less. That's the brakes over heating. They're only 9" drums, so they weren't meant for autocross. 10" brakes would be better, I'm sure, but she's gettin discs next.

No doubt! It depends on how you’re going to use the car. If it’s an infrequent driver that only sees the road in good conditions then the drums are ok.

For me, if you’re planning on doing regular driving, or driving in traffic, adverse conditions, etc then an upgrade is in order. I drive in too much traffic to trust all the knuckleheads around me will do the right thing
 
No doubt! It depends on how you’re going to use the car. If it’s an infrequent driver that only sees the road in good conditions then the drums are ok.

For me, if you’re planning on doing regular driving, or driving in traffic, adverse conditions, etc then an upgrade is in order. I drive in too much traffic to trust all the knuckleheads around me will do the right thing
....And we do. We drive this little car all over the place. We just have fun with it. So it will definitely be worth doing upgrades to, especially those that will make it safer to drive.
 
No doubt! It depends on how you’re going to use the car. If it’s an infrequent driver that only sees the road in good conditions then the drums are ok.

For me, if you’re planning on doing regular driving, or driving in traffic, adverse conditions, etc then an upgrade is in order. I drive in too much traffic to trust all the knuckleheads around me will do the right thing
...and that last paragraph reminds me of what Daddy drilled into my head talking about driving. He always said "watch the other fella" and he was dead right.
 
... While those are all good habits to have they do not guarantee that someone without good driving habits won't do something stupid and put you in a situation where you'd need better than 10" drums. Just takes one dipstick to cut you off and slam on the brakes, and if they're in something made in the last decade or two you've got no shot at stopping short with factory drums.

Sounds like you've been very fortunate for a very long time, which is great. But 10" brakes are not at all great by todays standards, and there are simple upgrades that can dramatically improve your stopping distances. Even just the factory disk brakes can improve stopping distances substantially, you don't need to go full pro touring to stop much better than you can with 10" drums all the way 'round. Now granted that will still put you at a disadvantage against a modern car, but if you knock a car length off your stopping distance that just might be a car you don't hit.

You absolutely can use good 10" drum brakes all around and have a safe car, "todays standards" are not that much better in day to day driving. I drove 1 hour minimum every day in Baltimore, MD rush hour traffic, every day for 25 years. I don't need the supposed superlative in everything for these cars. You guys can chase the latest and greatest in everything, but it is not required to have a safe fun car. Not sure what you call dramatic, I have not noticed huge gains in stopping from 10" drums to 73 up discs. The only vehicle I have driven with scary brakes was a 69 Chevy Pickup that simply took forever to stop at any speed.
 
You absolutely can use good 10" drum brakes all around and have a safe car,
I gave @66fs an agree on this, because I too spent years on 10inchers with not one accident due to insufficient brakes.
Are DB fronts better?
Logic says yes, but
I have also never been in a collision with a DB car, that can be blamed on poor brakes.
--------------------------
Ok here we go, again; This is my opinion;
For a car that rarely exceeds the speed-limit AND for a one-time max brake application: (eliminating brake-fade),
<it's all about the tires>
In 54 years of driving, I have never been in a collision that could have been avoided with better brakes. Wait a sec; how many collisions have I been in? I'm gonna say, that it took two to teach me to watch the other guy, and one in which I was fully stopped at.
So then, I can't actually speak to DB cars having shorter stopping distances. I mean I read the tests, but
I have never been in a situation where I needed to prove that.
Besides all that, ultimately
<it's all about the tires>

You can have the most awesome brakes on your car imaginable; and the tires are still gonna rule the stopping distance.
<it's all about the tires>
Of all the cars I've ever had, only the second one ever ran factory-sized tires, and only until they wore out. And it was probably the one car that I ever owned, that should have got bigger and better rubber on Day-One.
The Car? it was a 70 Swinger340, on Goodyear E70-14 Polyglass belteds. I learned to drive on those roller-skates. lol. Thank goodness the rear tires didn't last but the first summer. Then I transferred the front Polyglass onto the rear and installed new radials on the front, then proceeded to burn those Polyglassers off in the Second summer.
I had that car for 5 years and burned thru seven sets of tires.
That car was UNSAFE at any speed, regardless of the KH DBs on it,(maybe even parked); but, I never crashed it due to insufficient brakes. I did however crash it it into non-moving objects, like; ditches, signposts, and shopping carts. This, not for lack of brakes mind you, but, partly due to poor judgement on my part, I mean I was 17 when I got the car............. and partly because those Polyglass tires, were in fact, roller skates. Even just changing lanes could be an adventure.
<It's all about the tires>
My first Barracuda had 9inchers on it and D-something-14s . They were more than adequate, easily able to lock the tires at 30mph.
My second Barracuda had 10inchers and 205s on the front. Same deal.
My third Barracuda, I installed the KH DBs, cuz I knew this car was not gonna stay under the speed-limit 100% of the time, and it got 235/60-14s, then 245/50-15s. The 245s were sticky-tires and worked well but didn't last the summer, and were very very expensive. As for the 235s, well, same deal; locked them up easily at 30mph.
<It's all about the tires>
30mph is City Traffic, so that's what I cared about the most. So I began to increase the rear brake effectiveness, eventually settling on 295s in the back, with 10x2s and no proportioning. That gave me what I needed. Hitting the brakes at 30 is now like throwing out a big ol' Parachute; there is no need to lock up the front, which means I can steer around most situations.
<It's all about the tires>
For a city Mopar at up to say 3600 pounds/me in it, I would not be afraid to run 10" drums all 'round.
For a city Mopar at up to say 3300 pounds/me in it, I might consider 9inchers but Ima gonna pay more attention to the other-guy, and take it easy in the turns....... because; I gotta tell ya; I broke two 9" spindles already, with their tiny outter bearings, so not real interested in running those again.
In either case, I'm gonna run bigger than stock front tires, and fat-boys on the back, and NOT with the factory lame-azz proportioning.
For a City-car that will rarely exceed the speed-limit;
AND for a one-time max brake-application:
<it's all about the tires>
This is my opinion, after 54 years of driving.
Well actually, that has been my opinion, since I was 17,lol
 
All my 68-69 Roadrunner's and Coronet R/T's had drum brakes. I drove them all like I stole them . 383's and 440 4spd's . Never had a problem stopping. You just had to push hard on the peddle over 100 mph. You did not steer those cars with the F70-14's .You aimed them.

Also with those F70 tires you would lose traction before brake fade. So I was taught hit the brakes down shift , throw it sideways and power through with the rear tires lit up like Smoke bombs. If you needed to , Spin it 90 pull a gear and go the other way. Make sure you place your beer in the cup holder slid down in the window channel if you were using manual steering.

Not to go off the subject at all. But did any of you ever hold the throttle flat out and kick third gear without the clutch?
 
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Emailed Cass at Dr Diff and asked about these axles. Axle Pkg Stock Length Mopar 5X4 1/2" Bolt Pattern (pair) $298.00 Doctor Diff high-strength, 30 or 35 spline axle package. Question, are theses axles sufficient for 500+ HP?
His responce was, "I don't recommend ANY 30 spline axle for 500 hp if you drive the car hard, especially with a manual transmission. That is why NO manufacturer will warranty a 30 spline axle against twisting/breakage (Mark Williams, Strange, Moser, Currie etc...). 35 spline axles with a spool are fine, though."
Does any one have any experience with this product? I have read, even on thos forum that a stock 8.75 rear end could handle 500HP. and these are high strength axles. What are your opinons.
 
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