Want to stop that Z a little better? Craig
Marcho's Toyota 4X4 setup not manly enough for you? Want vented
front rotors? Read on!
I looked into this a while back, and may eventually do it. However,
talk of
replacing the (new) master with a truck unit seems like a little more than
I'm up for - so I'll probably go Craig Marcho's route, with the stock rotors
and truck calipers.
An interesting note about the calipers - I think Craig's article calls
for
the same rotors as the below mod. I think the vented rotors require
4Runner
calipers, not Truck calipers, but you'll hafta look to be sure....
Toyota 4X4/4Runner calipers (86-88)
Nissan Maxima rotors (85-88)
You'll need to machine the rotor:
New lug holes
New mounting holes
Bore out center for clearance
Then you'll need to shim the rotor out to center it in the caliper.
You may need to change the master cylinder to a Nissan truck (year?)
Thanks to Paul Richer, Steve Golik, and the mysterious Joe.
Here's some info someone sent me on this:
Kyle,
I have the following info which was forwarded to me by Steve Golik.
I have _not_ done the Maxima conversion, so I can't confirm any of this.
Good Luck.
Paul
--
Paul Richer
paulr@lsid.hp.com
>From goliks@knox.pcec.philips.com Tue Apr 15 08:01 PDT 1997
<SNIP HEADER>
> I pestered the s**t out of Randy Ayers of NWDE to figure out
> what was wrong with his info on the vented rotor conversion,
> and to his credit, he figured it out.
Good for you Joe! Thanks for being so persistent!
> First off he referenced the wrong calipers. He originally
> called out the 79-84 Toyota 4X4 calipers because he went by the
> casting number on the caliper. I told him that the these
> calipers would not work, and he discovered that between 86-89
> the exact same caliper casting was used BUT modified for a
> thicker vented rotor on the Toyota 4X4. So the '86-89 Toyota
> 4X4 caliper is the one that fits this conversion.
Yeah, I thought that this was the case...but according to my
brake cross reference manual, only the '86-'88 (and not the '89)
Toyota 4x4 calipers are the same.
Now the '89-'94 4x4 Toyota calipers WILL also work except that it
has more piston area, and the brake pads are larger in area. The
pistons have a total area that is over 25% more than the '70-'78
Z cars and therefore requires the 1" diameter Nissan truck master
cylinder to reduce pedal travel (this is my present setup on my
260Z).
> Second, we went round and round with that Maxima rotor. He
> finally went back and checked his original source on the info
> for the conversion, and found out that the '85-88 Maxima rotor,
> a front wheel drive rotor, has to be modified for the
> conversion....
After looking at the '88 Maxima rotor I obtained, I agree that
some machining must be done.
> The piloting bore for the hub has to be opened up to about
> 3.190" (I still have to measure the same bore on my original
73
> Z rotors just to make sure). And 4 new mounting holes have to
> be drilled to fasten the rotor to the hub. The existing holes
> for the wheel lugs are on a larger bolt circle, so you'll wind
> up having 8 holes in the rotor, you'll only use 4. Anyway,
> pretty straight forward mods to the rotor, should not be
> difficult or expensive.
I agree. This sounds like it's fairly easy machining operation.
However, my only concern is that I consider the rotor to be a
"wear" item and therefore it may require periodic replacement.
It
would be an expensive and unyielding proposition to have a new
rotor machined for each time it was necessary for replacement.
> Lastly, I'll have to gauge the position of caliper relative to
> the rotor to ensure that they are center to center. He mounts
> the rotor-hub assembly to the spindle in its normal fashion,
> and without the caliper fastened to its bracket, uses
> compressed air to expand the pads onto the rotor. He then uses
> a feeler gauge to measure the distance between the caliper
> mounting surfaces. This is then the thickness of the shim that
> is positioned between the hub and rotor. Haven't done it yet,
> but doesn't sound too difficult...Any comments or suggestion??
I don't know what expanding the pistons with compressed air is
going to accomplish. You don't even need to have the pads mounted
to determine the thickness of the shims. I would mount the rotor
(without any shims) and see if the caliper would bolt up without
any interference. If there was rotor-to-caliper interference,
then you would have to shim the rotor until you could mount the
caliper. Then I would just attempt to center the rotor exactly
halfway in between the opening in the caliper. There's not much
room there, so this is fairly critical. Oh, yeah I would use a
rotor that had very little wear for this, because a well used one
may have more wear on one side than the other. A NEW rotor would
be the best way to go.
Personally, I'm still a little pissed at Randy for allowing such
misinformation to be spread (especially via the Internet) and
then adamantly denying the errors in his article (at least to
me!). I wonder if he will go back and correct his web page?
BTW, I have been looking into another possible conversion for the
front brakes using a '86-'88 Toyota Cressida (vented) rotor. It
is the same outside diameter as the Maxima (and 300ZX) rotor, and
it may be easier to adapt (i.e., it would require little or no
machine shop work). I'll keep you posted.
Steve Golik
Did I screw something up? Forget to credit your part in this saga? 
Tell
me!