Rear disc brakes

I'll have to check calculations I did awhile back.  The 914 alloy wheels all have ET45 off set so that ends up being about 4.42" backspacing.  If the advertised 5" is correct I'd gain 1/2" clearance from the outer fender edge.  (I realize that isn't real accurate since there is still the outer tire rim and the width of the tire to consider too - but even 1/4" would be beneficial.  My concern is some of the Fuchs replicas say 4.5" which is same as the 2L wheels so no gain). 

Wish I had 1 CIP fake Fuchs on hand! Might be worth the $100 plus return shipping - but would really like to mount a tire which means they most likely wouldn't be returnable.

Michael McKelvey posted:

To get back to my original question, I called CB and was told this kit is 1/4" offset, although I am not 100% confident the women actually knew with certainty.

That would use up all the space I have on the driver's side between the tire and fender.

You can remove approximately 1/8-1/4" off of the rotor face to gain some clearance. I have about 45,000 miles on mine with no issues.

WOLFGANG posted:

I'll have to check calculations I did awhile back.  The 914 alloy wheels all have ET45 off set so that ends up being about 4.42" backspacing.  If the advertised 5" is correct I'd gain 1/2" clearance from the outer fender edge.  (I realize that isn't real accurate since there is still the outer tire rim and the width of the tire to consider too - but even 1/4" would be beneficial.  My concern is some of the Fuchs replicas say 4.5" which is same as the 2L wheels so no gain). 

Wish I had 1 CIP fake Fuchs on hand! Might be worth the $100 plus return shipping - but would really like to mount a tire which means they most likely wouldn't be returnable.

You could call their management and see if someone in warehouse could take exact measurements with pictures... They do respond to my calls.

WOLFGANG posted:

I'll have to check calculations I did awhile back.  The 914 alloy wheels all have ET45 off set so that ends up being about 4.42" backspacing.  If the advertised 5" is correct I'd gain 1/2" clearance from the outer fender edge.  (I realize that isn't real accurate since there is still the outer tire rim and the width of the tire to consider too - but even 1/4" would be beneficial.  My concern is some of the Fuchs replicas say 4.5" which is same as the 2L wheels so no gain). 

Wish I had 1 CIP fake Fuchs on hand! Might be worth the $100 plus return shipping - but would really like to mount a tire which means they most likely wouldn't be returnable.

Define "awhile back"...

Yesterday I ordered the AC Industries zero offset kit from SoCal. I ordered their master cylinder for 4-wheel discs too. They told me I don't need residual pressure valves for their brakes and said they are only needed for inferior copies.

I am having them install studs in the rotors for $20 each side for the installation.

The man in the link I posted above suggested painting the whole rotor and letting the pads wear off the paint where they make contact. I wonder if that would work with powder coating. I am planning on having the rotors and caliper brackets powder coated. I assume I can't do that with the master cylinder and calipers because of the heat.

Mike wrote: "The man in the link I posted above suggested painting the whole rotor and letting the pads wear off the paint where they make contact. I wonder if that would work with powder coating. I am planning on having the rotors and caliper brackets powder coated. I assume I can't do that with the master cylinder and calipers because of the heat."

hmmmmmmmmm.........   Veeery Interesting.

I put new rotors on our Outback and Rogue and the NAPA guys convinced me to go all-in with their Polymer coated rotors:

http://www.napabrakes.com/magn...s/ultra-premium.html

I do not know what the coating consists of, but they coated everything including the rotor faces.  The stuff wore off within a mile or so (lots of brake stomping involved, there).  

I do not know if this was a powder coating.  It seems to me that a number of heat-flowing powder coats are pretty hard once cured so I'm not sure if it is a good thing for a rotor face or not.  Paint or chromate?  Sure, but I can't speak to what's in powder coat mixes.  

On the Master Cylinder - Sure!  Powder coat all you want, just mask off all of the holes. Very little heat is generated in the M/C.

For the Calipers, just use high-heat powder coat, OR a high heat paint - they come in a bunch of colors (but no checkerboard if you're Cory Drake) and are typically good for over 600º.

Powder coating takes 200 degrees to cure - so rubber and plastic would be toast.  Calipers would have to be dismantle before powder coating.  The spray or brush on caliper paint is hi-temp and very durable (just prep according to directions).  You can even buy hi-heat BREMBO or ATE decals too (if you want to be a replica poser, i guess).

Michael McKelvey posted:

@TRP, do you mean rotate the caliper? How do you rotate with the brake lines attached? I guess one needs to bend them and disconnect the parking brake cable.

*facepalm* Yes, sorry.  Rotate the caliper ON the rotor so the bleed screw is at 12 o clock. Bleed the system. Rotate back when done.  You should have rubber lines between the metal lines and the pan. Unhook the metal horse shoe clip and slide thst union out of the retainer... That will give you enough play to rorate things without bending things. 

I wouldn't necessarily use your family's kitchen oven, though.  Especially when you can get a perfectly serviceable, used, Kitchen Oven for your shop from a place like a Habitat for Humanity "Re-Store" or Goodwill or even a free one from an appliance store that was removed when a new stove gets installed.  We had one in the car club down south and it was really handy.  All I have up here is an old counter-top toaster oven.

Valve covers for both the Speedster and the Mustang, exhaust pipes, my shift and 550 brake levers, the backs of my fog lights, a set of wrenches, a cast-iron piggy-bank thing, the tops of my carburetors, odds and ends in the shed, some of our Raleigh bicycle parts, a couple old Tonka trucks ... pretty much everything that can be baked in the ol' family oven ... has been.

I like to do that when Mrs. Drake is not at home, and thoroughly clean the oven afterward. I'm not big on residual bad stuff hanging around in there -- but if it comes down to me or the car, the car's going to last longer than I do anyway.

I'm sort of (not really) kidding.

PFFT.

Powder-coat doesn't off-gas at all. There are no distillates in the powder, so curing parts in the oven is probably safer than spraying that same oven down with Easy-Off. It's nothing at all like curing paint.

I'd love to build a big oven using an element and control from a cast-off electric range, but I'm still working out the design. 

I'll stick with my cast-off, Oster counter-top jobbie, thank you.

The one we got in Beaufort was a KitchenAid Electric range.  We actually got two that came from the same home, one was a single, YUGE! floor oven and the other was a wall-mount with an upper/lower config.  The big one could easily take a complete front A-Arm assembly from a full-size car, (or a 30 pound turkey) while the smaller ones were good for something up to brake drums and such.  NONE of them had heat accuracy worth a Dam so we used a BBQ thermometer to set the heat level - once set they would hold it to within 15 - 20 degrees or so.

Just another one of those things I wish I had room for (and many reasons to use it).

Art posted:

Greg;

Isn't that 5" back spacing worse  than our Fuchs 2L  wheels.

I think I have missed something.  in any event, I also have a pinky finger clearance at the rear drivers side .

Wolfgang, what I was trying to understand, is that the larger the backspace number, the further the distance from the outside edge of the wheel well?? ie rub spot ?

thanks, Art

Art posted:
Art posted:

Greg;

Isn't that 5" back spacing worse  than our Fuchs 2L  wheels.

I think I have missed something.  in any event, I also have a pinky finger clearance at the rear drivers side .

Wolfgang, what I was trying to understand, is that the larger the backspace number, the further the distance from the outside edge of the wheel well?? ie rub spot ?

thanks, Art

Yes, Art. The larger the backspacing, the closer to the outside the mounting surfacace is and the further in the wheel sits. 

Lol, I keep reading these posts and it gets confusing.  

"The larger the backspacing, the closer to the outside the mounting surfacace is and the further in the wheel sits. "

So... the larger the backspacing, the more space is given from the front rim edge of the wheel to the fender and thus provides more clearance with the fender. 

This will make the wheel rim look like it is a bottle cap, when placed on the hub, as nearly nothing of the rim is on the fender side and most of it is now sitting towards the   interior of the car.   as in the positive offset example below.

wheel-offset-backspace

 

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The deep dish look is kool on the ultra wide VS - but just can't work with a classic CMC rear.  The fake Fuchs at CIP1 say 5" back spacing so on 5.5" wheel that remarkable and hardly any to stick out and rub. A 4.5" wheel would work well but that is a skinny wheel and really too narrow for a 185 or probably 165 tire.

Check this wide 5 out - mounting surface has to be near flush with outer rim?

Photo

Negative Offset:

M50 on Firebird

Back in the day, this is what any self-respecting corn-fed white-boy aspired to. Mickey Thompson M50s on Cragar S/Ss sticking 3+" proud of the fender lips, air-shocks with 150 psi pressure so the bodywork would clear, chromed differential cover on the 12-bolt rear-end. Weight-transfer was horrible, but we all though the massive rubber made up for it. It was impressive when those big bias-ply meats broke loose.

This one must've had ladder bars, because I can't see any traction bars hanging under the leaves.

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I spoke to Andy at Socal who I presume is the owner.  He said he didn't realize the brakes were not quite zero offset.  He put a drum in a lathe and set the cutting tool to the face and then replaced the drum with my rotors and cut them to the same dimension. He mentioned they supply a lot of parts to Vintage Speedsters and he owns a Vintage Speedster.

edsnova posted:

FYI: 4.5-inch rims are fine for 165/80-15s and will fit 185/65s without complaint. I currently have a garage full of these combos. Also: my TD runs 4-inch MWS wire wheels with 165/80-15s.

According to Tirerack- recommended rim size for a 165/80 is 4-5.5" As the aspect ratio goes down the recommended rim changes- for a 165/60 it calls for a 5- 6.5" rim. For a 185/65 a 5-6.5" rim is also recommended. Beetle owners (as well as the occasional Speedster owner) put 185's on 4.5" rims all the time and with such light cars we get away with it, but some tire shops might not want to do it (I guess for legal issues that would pop up if something happened).

Yes, a 185/65 calls for a minimum 5" rim. But experience has shown that a 4.5" rim works just fine. Like I said on this EXACT SAME ISSUE over at Spyderclub, I personally have over 40,000 road and track miles that say this is OK. 

So instead of trying to scare people, name me any incidences you have of this tire/rim combo rolling off. I've heard of and experienced zero.

And it's not illegal to mount, just not recommended.

 

 Mr. Panhandle,

 I am a long time drag and road racer (40 + years). I once had an Anglia Gas Coupe which had 3” wide front rims and the appropriate (very narrow) rubber. No one would attempt any high speed turns with this set-up except in a dire emergency !

 But perhaps of more relevance is my experience with my own Beck Spyder. When purchased from Adriana Lima and her husband, the car had 200 miles on the clock, and needed to have both front and rear suspension “tuned” and aligned... which I did.

 After some 2000 mile I was disappointed at “tuck” (understeer characteristics). Since the Mangels wheels could not be balanced (massive runout), I got rid of them, and only then discovered that the front rims fitted with 185/65/15” rubber were 4 ½ inches wide…inadequate…in every way, and that explained why the tires in the front literally peeled off the rims in entry to sharp corners, irrespective of  normal  (1.4-1.7 bar) tire pressures.

If you don’t go fast…it really does not matter…but if you try to go fast with the wrong set-up... there is a guard-rail out there waiting to get to know you better

  ReV

Again, Rev, you have proven to be an ass over here as well as at Spyderclub.

My car has never been on a trailer except when it was delivered, smart ass. And I have driven that car pretty darn hard, as all my buddies over here will attest to.

Are you a politician? Deflect and don't answer, yup, that's what they do.

So I'll ask you again and make it in caps, not because I'm yelling, because I'm not. It's because I actually want an answer!

PLEASE GIVE EXAMPLE(S) OF 185/65R15 TIRES ROLLING OFF A 4.5" RIM.

Or just go away.......

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