LUVTruck.com

I have a 74' luv that had front disc brakes and rear drums when I purchased. I just installed a Ford 9" rear end. The package installed included a bolt on disc brake kit. Calipers are installed correctly (bleed screw up) and the system has been power bled; however, I am still having braking issues. The pedal is currently 4:1 and there is a small booster in the system.

I was going to leave the booster, but there is not enough room to upgrade it and the master cylinder. So, we were told to remove the small booster and just go manual. To do this, I was told that I need a new master cylinder (dual chamber), but that it needs a 7/8 bore on both sides to bring the front brakes up to the stopping power of the rear brakes and then I need to add a proportioning valve to help balance it all out. Further, I was told that the pedal will need to be brought to 7:1. This of course is not going to be as cost effective as I had hoped.

Does anyone have any other master cylinder (with or without booster) suggestions for a 74 luv w/V-8 swap, 9 in Ford rear end and 4 wheel discs all around (front and rear discs are different? I am not a brake guy and truly do not know where to start.

I am running one for a Chrysler mini van. Same as what strange sells

. No booster and a 5:1 pedal ratio. (7:1 doesn't sound right). I have wilwood fronts now, but ran the same setup with the stock fronts. I have the Lincoln Versailles factory nine inch rear discs...

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FIAA!

SFPP!

Ben had stock front brakes and rear discs on a nine inch. He ran the stock master and booster and it was fine. The pick shows a line lock for the front end.

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Certified pilots, looking down on people since 1903.

Our set up is currently the same as "Luvrv8", but we noticed that there is some type of possible proportioning valve installed on the fender well. It doesn't look as if it is adjustable. We have bled the system a couple of times and still have no pedal unless pumped 5 or 6 times. Do you think this valve should be removed or could it be a bad master cylinder? I looked at the reconditioned masters online and they say they are 7/8 in. bore, so I am unsure as to why I would need to run a different master. We measured the pedal and the brake guy who told us we needed to upgrade the master said the pedal was 4:1. Do you think a 4:1 pedal would be appropriate? Also, any thoughts on a residual valve for the rear? Any suggestions would be really helpful.

That is called a fail indicator.

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Certified pilots, looking down on people since 1903.

Does the fail indicator have a proportioning valve built in? I cannot find anything on it online. Does it need to be removed?

I removed mine when I plumbed it...

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It's really not needed, it just kicks a light if the pressure from back to front gets too far out of pressure differential.

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Certified pilots, looking down on people since 1903.

Do you think it could be causing a braking issue?

Never say never but I doubt it. It does not take much to remove, just remove it.

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Certified pilots, looking down on people since 1903.

Here are some links to the info i used . I also Have 7 to 1 with manual cylinder .
https://www.mpbrakes.com/techtalk/how-t ... edal-ratio
http://www.markwilliams.com/braketech.aspx
http://www.mcleodracing.com/info/?id=5262

7:1 it is then, if Hotrod says so...

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If you think no one cares, try missing a couple of payments...



FIAA!

SFPP!

I had to go like 7.7 on mine . I have aerospace brakes on mine . If your not an old man like me 5 to 1 will work good .

There is an adjustable rod from the stock booster that must be set at the correct length for the master to work properly. If you retain the stock setup make sure you check this.

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'78 Chevy LUV,1.9,4sp,headers,31's,SAS Dana 30,Dana 20,SOA rear w/Aussie Locker, rough body, bought new 12/4/78.
'87 Trooper,2.3,5sp,headers,31's,ball joint flip & spacer,Aussie Locker rear,Superwinch hubs,brush guard w/5.5K winch,more to come.

I've had 3 different brake setups on the back of a LUV (1 drum, 2 disc) and none of them had this problem. I think something else is wrong.

For example, one time I saw a set of rear calipers that weren't sliding on the pins. Same symptoms you described. We noticed that when you pumped the brakes a few times, that rotor would bend as the caliper clamped down. Then, when you let off, the rotor would push the piston back into the caliper, so next time you had to pump again.

I also had the factory set up with a 9inch ford and ford drums . It workrd great