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View Full Version : brake calipers on front of spindle vs rear



phenom08
02-23-2016, 07:13 PM
Whats the difference performance wise?

MasterSbilt_Racer
02-23-2016, 07:19 PM
Whats the difference performance wise?

No difference

Matt49
02-23-2016, 07:55 PM
MBR is correct. Think about the forces involved. When you hit the brakes, the caliper is trying to stop the rotation of the rotor/hub so the spindle (where the caliper is attached) wants to follow what the the hub is doing. So the top ball joint is being pushed forward and the bottom ball joint is being pushed backwards. Those ball joints have no idea whether the rotational resistance on the rotor is coming from the front or the back of the spindle.
This concept is what builds up to understanding how anti-dive or pro-dive work on a front end.

outlaw4j
02-24-2016, 07:30 AM
There is no performance difference braking force wise.

But when the calipers are mounted to the front they are more susceptible to mud and or stones pushing in, this can cause knock back of the brake pads and have temporary reduced brake force. You'll see in off-road applications where front mounted calipers also run a wiper to try to eliminate this.

swingarm4life
02-24-2016, 10:41 AM
MBR is correct. Think about the forces involved. When you hit the brakes, the caliper is trying to stop the rotation of the rotor/hub so the spindle (where the caliper is attached) wants to follow what the the hub is doing. So the top ball joint is being pushed forward and the bottom ball joint is being pushed backwards. Those ball joints have no idea whether the rotational resistance on the rotor is coming from the front or the back of the spindle.
This concept is what builds up to understanding how anti-dive or pro-dive work on a front end.

Great answer, stuff like this is why I love 4m most of the time.
I asked CJ the same question one time and this was his answer
He said "You ever look out in a field and see one of those big round hey bails?"
I said "Yes sir, but what in the he!! does that have to do with brakes?"
He said "You know, if you got one of those things rolling down a hill it would be dam hard to stop it from behind. But if you got in front of it, you could stop it if you tried hard enough"
Just to get him worked up like I didn't understand what he was talking about, I asked what kind of freaking idiot would get in front of a moving 1000 pound hey bale. I'll get banned if I put his response on here.

Matt49
02-24-2016, 05:42 PM
Great answer, stuff like this is why I love 4m most of the time.
I asked CJ the same question one time and this was his answer
He said "You ever look out in a field and see one of those big round hey bails?"
I said "Yes sir, but what in the he!! does that have to do with brakes?"
He said "You know, if you got one of those things rolling down a hill it would be dam hard to stop it from behind. But if you got in front of it, you could stop it if you tried hard enough"
Just to get him worked up like I didn't understand what he was talking about, I asked what kind of freaking idiot would get in front of a moving 1000 pound hey bale. I'll get banned if I put his response on here.

With all due respect to CJ (and much is due), that answer is a very poor analogy. But I think you had that figured out :-)

m_stagev
02-24-2016, 06:07 PM
With all due respect to CJ (and much is due), that answer is a very poor analogy. But I think you had that figured out :-)

putting the caliper bracket in front makes the steering arm stronger and harder to bend but i have ran that deal and when the arm does get bent it locks the wheel up and usually ends up with a trip into the fence.

RCJ
02-24-2016, 09:10 PM
It would effect the polar moment somewhat.When Everham was with Gordon I notice he was mounting the rear calipers to the front of the axle.

Brian Gray
02-24-2016, 09:44 PM
As far as stopping forces are concerned no difference. Polar moment now your onto something but the 1 big detail you missed is the gyroscopic effect that is encountered when you have mass placed upon the axle . If you think about it too long you have already missed the point. Regardless understanding the physics behind this isn't going to improve your program enough to matter. I'd be concerned about the reliability you will gain by keeping the caliper away from damage.

swingarm4life
02-24-2016, 10:21 PM
Matt, CJ has a ton of these analogies. Some make a lot of sense and some make absolutely none. But they are all hilarious. I'm not sure if his cars are the same now, but back in the day every suspension bolt on the car could be removed with a 1 1/8" wrench/socket. I asked him if he could build ours with all smaller bolts/nuts. He said "What for, then you'll just have to buy more tools and carry more wrenches around in your pocket". Makes perfect sense! He is one cool cat though

JustAddDirt
02-25-2016, 08:27 AM
Matt, CJ has a ton of these analogies. Some make a lot of sense and some make absolutely none. But they are all hilarious. I'm not sure if his cars are the same now, but back in the day every suspension bolt on the car could be removed with a 1 1/8" wrench/socket. I asked him if he could build ours with all smaller bolts/nuts. He said "What for, then you'll just have to buy more tools and carry more wrenches around in your pocket". Makes perfect sense! He is one cool cat though

The best one I remember from CJ is:
spoke to him about a couple things back in 2003. asking this and that...
His response:
Boy what do you do for a living?
I told him....
he said. Well son, I build racecars, so listen to what I tell ya'.

lazermod3
03-03-2016, 04:31 PM
End result,do not pass go and head for the (HOT DOG STAND!)

RacerX10
03-03-2016, 08:29 PM
End result,do not pass go and head for the (HOT DOG STAND!)

When I'm having a bad night at the track, I always go to the hot dog stand, thinking of CJ's advice.

It never works, but I always do it.

lazermod3
03-04-2016, 05:50 PM
When I'm having a bad night at the track, I always go to the hot dog stand, thinking of CJ's advice.

It never works, but I always do it.

Here's the deal,When eating the (HOT DOG,) you should be pondering about your next chassis setup!

RacerX10
03-04-2016, 09:02 PM
Here's the deal,When eating the (HOT DOG,) you should be pondering about your next chassis setup!

Aha !

See .. I've always just ate the hot dog and considered the error of my ways. I'll try your way next time :)

fox1162002
03-04-2016, 11:38 PM
I remember back in early 2000's a buddy of mine had a Rayburn and he changed the swing arm birdcage and modified it. He took the car to CJ well CJ looked at my bud an told him God couldn't drive that car my friend told him God didn't own that car. I always enjoyed seein CJ get worked up.

SuperEight
03-07-2016, 09:29 PM
It would effect the polar moment somewhat.When Everham was with Gordon I notice he was mounting the rear calipers to the front of the axle.

Doing it in the rear of the car is a totally different deal. Their talking about in the front of the car, back or front of the spindle.