Strange front brake dilema

Posted By: 67446DART

Strange front brake dilema - 10/14/12 11:56 PM

Hi All,
I just got a cap front end installed on my 67 dart street/race car....car weights 3120lbs without driver...it is the coilover and rack and pinion set up.I also changed the 73 and up disc brakes for a set of strange drag race brakes part # B-4160wc the car has the mopar performance aluminium master cylinder and a willwood adjustable proportioning valve the rear brakes are 10" stock drums.The problem I am having is on even the shortest trips the rotors get hot and they get glazed hot spots on them and the pads get real smooth from this...I feel the steering wheel vibrate pretty bad!! I had the rotors turned,new pads from strange and the proportioning valve turned all the way down.It still is doing this If i hadn't already sold the stock stuff I would just give up on the race brakes!! I taked to strange and they said the car is to heavy for this brake set up,and they only sell 1 type of pads for these calipers.

Posted By: MR_P_BODY

Re: Strange front brake dilema - 10/15/12 12:07 AM

Do the rotors spin freely before you drive.... is
the prop valve on the front brakes... open it all
the way

Posted By: jamesc

Re: Strange front brake dilema - 10/15/12 12:22 AM

i realize this is of no help but that is a race brake setup and imho should not be used on any street driven car. i have the same setup for my dart which i hope comes in at #3000 or less and will be strip only. i'm surprised that they didn't say anything about street use when you called them.

Posted By: MR_P_BODY

Re: Strange front brake dilema - 10/15/12 12:29 AM

Quote:

i realize this is of no help but that is a race brake setup and imho should not be used on any street driven car. i have the same setup for my dart which i hope comes in at #3000 or less and will be strip only. i'm surprised that they didn't say anything about street use when you called them.

I guarantee they said its race only.... I have the
Strange struts with the same brakes on my Rampage
and they said it many times but I'm running them
on the street but in a much lighter car

Posted By: MPerry

Re: Strange front brake dilema - 10/15/12 12:30 AM

What is considered a short trip? That is a pro race setup with rotors that are .350 thick. Its not going to take much for them to get hot if your driving on the street.

http://www.summitracing.com/parts/STR-B4160WC/

Posted By: 67446DART

Re: Strange front brake dilema - 10/15/12 12:38 AM

i drove the car to a car show maybe a total of 8 miles never really got on it and didnt use the brakes hard at all.These brakes were on a project car I bought i put the brakes on my car and sold the car they came off of.Strange did say they are not for street use.What brake set up do you guys recomend?preffer them to be lighter than stock....i need to get this fixed....honsestly im affraid to drive it like this!

Posted By: MR_P_BODY

Re: Strange front brake dilema - 10/15/12 12:46 AM

With the front end up do they spin freely... next, hit
the pedal and see how long it takes to spin them again...
open the prop up so the fluid can return

Posted By: SB412DUSTER

Re: Strange front brake dilema - 10/15/12 04:53 AM

If you check them and if they dont turn easy make sure the master cylinder push rod is not to long. an easy way to check is to loosen the bolts that hold the master on and see if the brakes free up

Posted By: moparniac

Re: Strange front brake dilema - 10/15/12 07:54 AM

Quote:

Hi All,
car weights 3120lbs without driver...

Quote:

i realize this is of no help but that is a race brake setup and imho should not be used on any street driven car.

my car is 3400 with driver (I am 250)and they work fine for me! I posted this question a while back on the bullet and Larry Larson even replied and Jeff Lutz ran the strange brakes up front also (yes the thinner strange ones)If them 2 guys don't have issues with their 200mph street cars and "race only brakes"... something else is wrong with your setup

go to 2:00 in the video. brakes look familiar. lutz is 3600lbs in that car also.

http://www.youtube.com/watch?v=K7xOOOh89a8

Posted By: Dartin

Re: Strange front brake dilema - 10/15/12 10:26 AM

Quote:

Quote:

Hi All,
car weights 3120lbs without driver...

Quote:

i realize this is of no help but that is a race brake setup and imho should not be used on any street driven car.

my car is 3400 with driver (I am 250)and they work fine for me! I posted this question a while back on the bullet and Larry Larson even replied and Jeff Lutz ran the strange brakes up front also (yes the thinner strange ones)If them 2 guys don't have issues with their 200mph street cars and "race only brakes"... something else is wrong with your setup

go to 2:00 in the video. brakes look familiar. lutz is 3600lbs in that car also.

http://www.youtube.com/watch?v=K7xOOOh89a8

I agree. I realize that repeated braking on the street is not the same as stopping once on the track, but If it is doing this at lower speeds just imagine how it will be at race speeds.I run this set up on my Dart Sport with no issues on the street or track. Sounds like something is not right. Too tight wheel bearings, calipers not releasing, etc.

Randy

Posted By: MR_P_BODY

Re: Strange front brake dilema - 10/15/12 01:01 PM

Also did you replace the brake hoses on it... they
could be collapsed

Posted By: Dodgem

Re: Strange front brake dilema - 10/15/12 01:57 PM

maybe the master rod is not adjusted right and it is holding pressure on the brakes. jack it up pump up the brakes and see how the wheels turn should be next to no friction!!!

Don't some drum brake masters hold 10 lb of residual pressure??

Posted By: TheBlackCar

Re: Strange front brake dilema - 10/15/12 02:02 PM

Swap lines on master.
You can also use a 10# residual on line to rear with the drum brakes.

Posted By: Guitar Jones

Re: Strange front brake dilema - 10/15/12 05:38 PM

The proportioning valve should be spliced into the rear brakes only, but with your setup I wouldn't even use one. Make sure the calipers aren't hanging up or the hoses coming apart on the inside. I wouldn't run a residual valve if the master cylinder is in the stock location. Also make sure you have some brake pedal pushrod to master cylinder free play. If it's too tight it will just keep pumping the brakes up.

Posted By: JAKE68

Re: Strange front brake dilema - 10/15/12 06:36 PM

I had a simmular problem with a customers car that he wanted the race brakes on front with rear drums. Went through several sets of pads and some rotters in a short period. Took the rear drums off and put disc in back a problem was gone. The rear drums are not as effective as the front disc so you really load the brakes to stop putting a ton of heat in the fronts.

Posted By: MR_P_BODY

Re: Strange front brake dilema - 10/15/12 09:08 PM

Quote:

The proportioning valve should be spliced into the rear brakes only,

I totally disagree with this... its there to SLOW the
fluid to the front brakes to keep the front tires
from skidding on a spike

Posted By: JAKE68

Re: Strange front brake dilema - 10/15/12 10:14 PM

Hey Raf we usually put them to the rear because when braking hard and the car nose dives the rears will lock up so you have to control that. allot of Chrysler m/c have a 70/30 f/r built in them already. If it is a big tire car we don't even use one.

Posted By: moparniac

Re: Strange front brake dilema - 10/15/12 10:16 PM

I have strange front and rear just straight hard lined in all around.

Posted By: TheBlackCar

Re: Strange front brake dilema - 10/15/12 10:17 PM

MP master cylinders were roughly 70/30 front to rear. Your putting the majority of fluid to the aftermarket front disc (better) brakes, which end up being the only thing stopping the car (ie reason for heat).

Been thru this one a few times

Good Luck

Posted By: Guitar Jones

Re: Strange front brake dilema - 10/15/12 10:19 PM

Quote:

Quote:

The proportioning valve should be spliced into the rear brakes only,

I totally disagree with this... its there to SLOW the
fluid to the front brakes to keep the front tires
from skidding on a spike

Although I respect your opinions, and you are indeed knowledgable if you read the DC manual it will tell you it reduces pressure to the rear brakes to prevent the rear from locking up first. That would create an uncontrollable vehicle. All proportioning valves reduce pressure to the rear brakes. If you don't believe me make a call to Strange or Mark Williams.

The exception to this is heavy trucks like semi tractors, they apply more force to the rear brakes because of the load they carry. That is what makes a bobtail tractor or an empty trailer more difficult to drive.

As I said earlier and has been stated above the rear drums are not as effective as the discs. The MP master cylinders already reduce pressure to the rear brakes so in this case I wouldn't even use one. The ports on the master cylinder are marked F and R for front and rear.

Posted By: Guitar Jones

Re: Strange front brake dilema - 10/15/12 10:21 PM

Quote:

MP master cylinders were roughly 70/30 front to rear. Your putting the majority of fluid to the aftermarket front disc (better) brakes, which end up being the only thing stopping the car (ie reason for heat).

Been thru this one a few times

Good Luck

I think it's more like 60/40.

Posted By: JAKE68

Re: Strange front brake dilema - 10/15/12 10:24 PM

Quote:

Quote:

MP master cylinders were roughly 70/30 front to rear. Your putting the majority of fluid to the aftermarket front disc (better) brakes, which end up being the only thing stopping the car (ie reason for heat).

Been thru this one a few times

Good Luck

I think it's more like 60/40.

Depends on which model of vehical it was originaly intended for.

Posted By: TheBlackCar

Re: Strange front brake dilema - 10/15/12 10:29 PM

63/37 and 69/31 if we need to be exact. Thought "roughly 70/30" was close enough.

Posted By: 67446DART

Re: Strange front brake dilema - 10/15/12 10:42 PM

Thanks for all the suggestions on this I am really getting frustrated with the car to be honest! I guess I should start at the begining and say I got the front end on including the brakes in question , I think there were about 2 or 3 turns on the valve at this point and took it to my local track 75/80 and made (4) 1/4 mile passes it did the same stuff I mentioned before.I took it home turned the rotors and put new pads in and turned the proportioning valve all the way back....this is where I am now.

car has stainless front lines on it.I keep the car at my dads place so the next time I get over there i will try some of your suggestions...Thanks all!!

Posted By: 67446DART

Re: Strange front brake dilema - 10/15/12 10:46 PM

this is a link to pic's of my car if you want to see what it looks like...

http://www.lbsr.org/DavesDart.html

Posted By: JAKE68

Re: Strange front brake dilema - 10/15/12 11:11 PM

Quote:

Thanks for all the suggestions on this I am really getting frustrated with the car to be honest! I guess I should start at the begining and say I got the front end on including the brakes in question , I think there were about 2 or 3 turns on the valve at this point and took it to my local track 75/80 and made (4) 1/4 mile passes it did the same stuff I mentioned before.I took it home turned the rotors and put new pads in and turned the proportioning valve all the way back....this is where I am now.

car has stainless front lines on it.I keep the car at my dads place so the next time I get over there i will try some of your suggestions...Thanks all!!

To put more pressure to the rears u turn the prop valve in. Out restricts pressure to rears. Believe me I did it wrong for years.

Posted By: MR_P_BODY

Re: Strange front brake dilema - 10/16/12 12:22 AM

What you guys are reading in that 70/30 split is NOT
the valving... its the volume of the reservoirs...
if the car noses over then yes the rear gets lite
BUT MOST of use have strong springs in the front and
SKINNY tires... all the cars I have built with skinny
front tires get the prop valve installed in the front
lines to keep from locking up the fronts on a spike

Posted By: 67446DART

Re: Strange front brake dilema - 10/16/12 12:54 AM

Quote:

Quote:

Hi All,
car weights 3120lbs without driver...

Quote:

i realize this is of no help but that is a race brake setup and imho should not be used on any street driven car.

my car is 3400 with driver (I am 250)and they work fine for me! I posted this question a while back on the bullet and Larry Larson even replied and Jeff Lutz ran the strange brakes up front also (yes the thinner strange ones)If them 2 guys don't have issues with their 200mph street cars and "race only brakes"... something else is wrong with your setup

go to 2:00 in the video. brakes look familiar. lutz is 3600lbs in that car also.

http://www.youtube.com/watch?v=K7xOOOh89a8

interesting....what master cylinder are you using?

Posted By: DoctorDiff

Re: Strange front brake dilema - 10/16/12 04:19 AM

The prop valve may be installed in the front line if you are running "skinny" front tires. In this case, you must rely on the rear brakes to do the majority of the work because the front tires lack the necessary tread width to stop the car.

This is not ideal, but it is better than the alternative.

Posted By: 67446DART

Re: Strange front brake dilema - 03/16/13 09:23 PM

Ok thanks for all the replys....Spring is approching and I want to get my car going again! I am contumplating buying different style aftermarket brakes or going back to stock style.....in that case I will be looking for some of the stock hardware if you are reading this and have some of it message me!

I forgot to mention I still am running a (new) stock 73 duster proportioning valve as well in addition to everthing else above.
Thanks for your time all!

Posted By: Cab_Burge

Re: Strange front brake dilema - 03/17/13 05:39 AM

Make sure your master cylinder does not have a residual pressure valve in the part feeding the front brakes

Some of the Mopar aluminum master cylinfers had them in both ends is what someone on here said, probally the ones for the ealry K cars, is what I remember

The master cylinder rod adjustment from the brake pedal will do that also