Bob Paulin, WZJunk-Narrowing 79 Camaro Subframe

[Ralph]

Hi Guys
Gonna need a little more help here. I'm attempting the Metric Rotor swap onto a 79 Camaro subframe that you offered advise on a little while ago. Supposed to narrow the wheel mountings an inch per side.I picked up the NAPA Part # BR-6 and BR-09074 bearings today. Then I hit my first snag.

When I asked for the rotors, my parts guy didn't know what year and model a 108'' Metric Chassis was (and neither did I.)He gave me rotors from an 82-88 Monte Carlo to try.They're a 10.5" and my rotors are 11". He also said the 79 Camaro uses the same caliper as the 80's Caprice caliper you reccommended for the job.I took the rotors home to try anyway and the spec'd rotors and bearings moved the rotor out about .25 inch from stock position relative to the caliper mount. Did seem to narrow the track some, though. So....

What year and make 11" rotor should I ask for?
Is there a particular year of caliper I need, or is my parts guy wrong about the interchangeability?

I'm going back to the parts store tomorrow for another crack at this. Any more info you could give me on this would help. I'm not ready to give up yet!
Thanks,
Ralph

[Bob Paulin]

Hi Guys
Gonna need a little more help here. I'm attempting the Metric Rotor swap onto a 79 Camaro subframe that you offered advise on a little while ago. Supposed to narrow the wheel mountings an inch per side.I picked up the NAPA Part # BR-6 and BR-09074 bearings today. Then I hit my first snag.

When I asked for the rotors, my parts guy didn't know what year and model a 108'' Metric Chassis was (and neither did I.)He gave me rotors from an 82-88 Monte Carlo to try.They're a 10.5" and my rotors are 11". He also said the 79 Camaro uses the same caliper as the 80's Caprice caliper you reccommended for the job.I took the rotors home to try anyway and the spec'd rotors and bearings moved the rotor out about .25 inch from stock position relative to the caliper mount. Did seem to narrow the track some, though. So....

What year and make 11" rotor should I ask for?
Is there a particular year of caliper I need, or is my parts guy wrong about the interchangeability?

I'm going back to the parts store tomorrow for another crack at this. Any more info you could give me on this would help. I'm not ready to give up yet!
Thanks,
Ralph

Sorry, but I have given you everything that I had written down.....and, at my age, if it isn't written down....well, you know!

It sounds to me as though you have the right "Metric" rotor - from a 108" chassis, and I seem to remember modifying the caliper bracket. We had pirated parts from an oval-track racing friend's stockpile of Metric spares.

The pre-'82 108" chassis used smaller wheel bearings - another reason for me to believe you've got the right one since most oval-trackers stockpile the '82-up stuff for the bigger bearings.

I believe the '87-up Monte was a FWD, and I cannot imagine the same front rotor fitting both FWD and RWD cars.

Did you look at the earlier ('78-'81) 108" chassis rotor? The intermediate 108" RWD Metric ran from '78 up to '85 or '86 depending on the car line.

If I could see the setup and do some measuring, it might jog the ol' memory.

Sorry I can't be of more help right now. It's really been quite a while since I did that particular swap.

Bob Paulin

[WZ JUNK]

You should be able to lay the rotors down on a flat surface and see the difference where the wheel bolt flange is.  The new rotor bolt flange will be closer to the disc area.  I think the rotor you need may also be used on S 10 pickups.

The caliper you want is different than the Camaro.  It is used on half ton pickups and the Caprice.   You will also need the longer bolt/pins used on these calipers and you will need to do some minor grinding on the spindle.

Contact me if you have prolems and I will try to walk you through this.  It can be done.

[Phil1934]

From an old HAMB post.  Rotors are Monte Carlo or S10.  Calipers are '79 1/2 ton PU.  Pads are 52 Wagner.  Outer bearing and race are Federal Mogul A2.  This setup did move the piston out of the caliper an additional 1/4" so sounds like you have similar parts.  Also some grinding was required in the caliper mount area.  Keep us posted as doesn't seem like anyone has done a follow up after getting it on the road.

[Ralph]

Well, so far, NO good. Here's what I've got so far:
The 82 - 88 Monte (also fits S-10) rotor is 3/8" thinner laid flat on the ground to the wheel bolt surface, than the 79 Camaro.

Mounted on the spindle it sits almost 1/4" further out than stock. Somehow when I mount the rotor on the spindle it does narrow the track about 5/16". But when you consider using 10.5" rotors on a spindle made for an 11", so the brake pads don't contact properly, and having to space out the caliper 1/4", the gain of 5/16" isn't worth it.

If this swap has been done successfully by others, Then I must have the wrong parts. More wrecking yard research required. Stay Tuned for our next installment!

[WZ JUNK]

Well, so far, NO good. Here's what I've got so far:
The 82 - 88 Monte (also fits S-10) rotor is 3/8" thinner laid flat on the ground to the wheel bolt surface, than the 79 Camaro.

Mounted on the spindle it sits almost 1/4" further out than stock. Somehow when I mount the rotor on the spindle it does narrow the track about 5/16". But when you consider using 10.5" rotors on a spindle made for an 11", so the brake pads don't contact properly, and having to space out the caliper 1/4", the gain of 5/16" isn't worth it.

If this swap has been done successfully by others, Then I must have the wrong parts. More wrecking yard research required. Stay Tuned for our next installment!

I will be going to the shop later this morning and I will take some measurements.  I have a spindle and the two rotors in my store room somewhere and I will set them up and take some measurements.  I think that if you compare the two by measuring from the end of the spindle to the flange where the wheel mounts,  there is more change than you noted.   The offset of the caliper has nothing to do with the narrowing of the track by changing the rotors.  The slight overlap of the pads pass the outer edge of the rotor is not a prolem as the pads will wear to shape of the diameter of the rotor.  I guess you could cut off that part of the pad if you do not like the looks of it.  Be mindfull of the dust if you do this.

[Ralph]

Well, so far, NO good. Here's what I've got so far:
The 82 - 88 Monte (also fits S-10) rotor is 3/8" thinner laid flat on the ground to the wheel bolt surface, than the 79 Camaro.

Mounted on the spindle it sits almost 1/4" further out than stock. Somehow when I mount the rotor on the spindle it does narrow the track about 5/16". But when you consider using 10.5" rotors on a spindle made for an 11", so the brake pads don't contact properly, and having to space out the caliper 1/4", the gain of 5/16" isn't worth it.

If this swap has been done successfully by others, Then I must have the wrong parts. More wrecking yard research required. Stay Tuned for our next installment!

I will be going to the shop later this morning and I will take some measurements.  I have a spindle and the two rotors in my store room somewhere and I will set them up and take some measurements.  I think that if you compare the two by measuring from the end of the spindle to the flange where the wheel mounts,  there is more change than you noted.   The offset of the caliper has nothing to do with the narrowing of the track by changing the rotors.  The slight overlap of the pads pass the outer edge of the rotor is not a prolem as the pads will wear to shape of the diameter of the rotor.  I guess you could cut off that part of the pad if you do not like the looks of it.  Be mindfull of the dust if you do this.

Hey WZ - I've been off camping with the family for a bit. Two good days, three cold and rainy. We're back now, and it's hot as hell. My usual luck! Have you had a chance to look into the disc swap?
Ralph

[WZ JUNK]

I will take some measurements this morning.  I have one of the rotors and spindles with the metric rotors set up in my storage room and I have a Camaro subrame in my outdoor storage(junk pile) behind the shop.  As soon as the dew is off of the grass, I will take some measurements.  

I do not understand what is going on as when I originally did this I took measurements and they were different than what I got the other day.

[WZ JUNK]

Well, I have done some measuring today and I can not for the life of me figure out what is going on.  I have not used this setup for some time and I know that when I did in the past I was able to narrow the track significantly.  However, I can not get that change now.  I make it to be between 3/8 and 5/16 inch difference on each side for a total change of 3/4 to 5/8 inch overall.  Thats not enough to be worth the change for most applications.  I have the spindle in the shop vise and all of the stuff there.  I will look at it some more tonight and tomorrow and maybe I can figure out what I did differently before.   Kinda like an old man with a young girl friend, I will just sit around and look at it.

[Ralph]

Thanks, WZ. That's exactly the result I got. I'l keep pondering, and bugging my parts man, too. If it worked before...............
Ralph