1968 Chevelle SS 396 - Best Disc Brake Conversion Kit

[Shovelrick]

Make sure the brakets that hold the calipers on are on correctly, I think thats the problem and if anything needs to be shimmed start with the bracket to spindle and like already said rotor needs to be centered with pads left out so you can see it clearly PS IIRC that was in the Wilwood instr. sheet and I think it would work for any brand brakes, I'll look to see if I still have those instructions and take a pic or you could probably go on Wilwoods website and read it, it might more sense than what Im typing

 

[Shovelrick]

I still have these parts left over off my 68 if you want them you can have them, rotors are garbage

 

[arico80]

Well, I'm done %$#@ing around with this thing and the car gods have shown me the way. By accident, I stumbled into this performance shop today and I completely misjudged this place. Its actually a performance machine shop! Guys are gonna grind down my calipers slightly to fit nice. Just gotta wait for a new caliper because I destroyed the tread on one of the mount screw holes, whatever. I'll get you all an update when it's done.

 

[Nashville Cat]

Well, I'm done %$#@ing around with this thing and the car gods have shown me the way. By accident, I stumbled into this performance shop today and I completely misjudged this place. Its actually a performance machine shop! Guys are gonna grind down my calipers slightly to fit nice. Just gotta wait for a new caliper because I destroyed the tread on one of the mount screw holes, whatever. I'll get you all an update when it's done.

That's awesome to find a place like that

 

[arico80]

Ok, well got the left rear drum replaced and updated, working on right rear. Got both calipers and gonna take them to the machine shop this week to get trimmed. Getting closer.

Oh and thanks Shovelrick, if this doesn't work out for some reason I'll let you know.

 

[arico80]

Hey there folks, sorry it took so long for an update. Well, the C5 front disc brakes are all mounted and ready to go. In case anyone was curious, had to shave off about 0.075" from the top mounting point of each caliper. They spin free now with pads and no rubbing. Also finished replacing both rear drum brake systems (shoes, springs, wheel cylinders and drums). Right now I'm waiting for a new hose, valve, and bracket for the rear brake line that mounts to the top of the differential. While I'm waiting, I started working on the master cylinder and power booster. Question, when you install the power booster with the MC, do you still need the brake pedal return spring? That damn spring and associated pin are the reason I stopped working on it today and I see a few people have commented that the power booster returns the brake pedal to the forward position. If I don't need it then I'm buying a nice set of bolt cutters and cutting that thing. Gonna start cutting, bending and flaring my copper-nickel brake lines hopefully tomorrow. See below for some progress pics...

 

[Nashville Cat]

Looking good !

 

[arico80]

Making some good progress, with a little luck the entire braking system should be complete this week! Two questions though...

1. Where should I connect the vacuum line on the power booster? There seems to be additional ports on the carburetor but wanted your folks' thoughts...see pics attached.
2. Can i connect the electrical line from the valve to the spooled wires i have pictured here? i'm guessing I might have to wire up the battery and test the lines first with a volt meter? Am I overthinking this?

 

[kmakar]

Usually the vacuum line to the brake booster comes directly off the intake towards the rear.

I may be wrong, but that electrical connection on the distribution block goes to a dummy light on the dash...

 

[Shovelrick]

I have my booster Tee'd with the PCV valve at the back of my carb, works fine

 

[cheveslakr]

Should be a brown wire for the dummy light on '67 and later models.

 

[Nashville Cat]

The brake booster line comes off the 3/8 pipe vacuum port on the intake. (Circled in purple).



Here's what a typical fitting looks like. The big side goes to the booster and I run the small side to the distributor

Amazon.com

 

[JohnC]

Is that your engine Beth? SHINY!!

 

[Nashville Cat]

Is that your engine Beth? SHINY!!

Nope, this is mine :

 

[JohnC]

I like yours better, more original.

 

[arico80]

Well, I officially finished the job and got the car on the road this passed weekend. Had a minor leak in 1 or two spots but nothing a few extra wrench turns didn't solve. The wheels fit perfectly as well, went with REV's 17x8's on 235 50 R17s in the front. Just wanted to thank all of you that helped me out with this. Now I've gotta figure out how to adjust the timing correctly because she's backfiring a little bit at idle. Posted some pics of final product, piping won't win any beauty contests but it don't leak either.

 

[Nashville Cat]

On your timing troubleshooting, make sure the vacuum advance is working.
The engine should slow down when you unplug the vacuum line at the distributor.
Initial timing should be ~ 12 to 16 degrees.

 

[Shovelrick]

If you have a performance type cam, disco vacuum and plug it, time to 35* at 3,500 rpm (my engine builder likes no vac adv and 35* @ 35k) let it idle and see where it falls, hook full manifold vac up and see what you have, IIRC my cruise timing is mid 40's last 454 cruise was 52* and ran like a scalded dog, no detonation, I have an MSD stop plate set at 10* in my PerTronix flame thrower III

 

[cage2592]

Mine is 16* at idle and 36* at 3000rpm. Vacuum plugged on mine also.

 

[arico80]

Vacuum already plugged, see photos below. From what I've read, it seems like the vacuum helps you out at idle and cruising speeds but not W.O.T. I was thinking of connecting it to the blue port at the front of the motor in the last picture but sounds like you guys think I should be setting the timing with the vacuum not connected.