Jump to content


Photo
- - - - -

240z S12W+280zx disc conversion


  • Please log in to reply
36 replies to this topic

#21 seattlejester

seattlejester

    Totally Addicted

  • Donating Members
  • PipPipPipPipPipPip
  • 1865 posts
  • LocationBellevue, WASHINGTON

Posted 14 December 2016 - 04:44 PM

I was surprised with how much it moved while just bleeding the brakes, I mean that is a fairly passive motion, imagine if you are actually trying to stop. It goes directly forward so I would think something from like the strut tower would be ideal so that it is not pulling laterally on the fender or something. I guess the best bet would be to weld in reinforcements while everything is out. The FRS seems to suffer from this problem.

 

http://www.ft86club....ead.php?t=21238

 

I'm thinking a triangulated bracket using one or two of the strut tower bolts and maybe a third point drilled into the side of the shock tower for the third leg with a similar bolt/cushion setup would be pretty effective.

 

Another fun one to think about is getting under the car while someone bounces up and down on the seat, seeing that panel flex is pretty crazy. 



#22 grannyknot

grannyknot

    Always Here

  • Members
  • PipPipPipPip
  • 171 posts
  • LocationOntario

Posted 19 December 2016 - 04:25 PM

So I have been trying to figure out a way to install braces to the firewall but they end up being too elaborate and convoluted so I just tried something simple like the brace on the FRS link, just started on it this morning so it still looks pretty rough but I think it will do the job. I'll post more pics when it is cleaned up and installed.

Attached File  DSCN0936.JPG   231.59KB   1 downloadsAttached File  DSCN0937.JPG   227.84KB   0 downloadsAttached File  DSCN0940.JPG   232.97KB   0 downloadsAttached File  DSCN0942.JPG   232.21KB   0 downloadsAttached File  DSCN0941.JPG   231.8KB   1 downloads

 


Edited by grannyknot, 19 December 2016 - 04:27 PM.


#23 seattlejester

seattlejester

    Totally Addicted

  • Donating Members
  • PipPipPipPipPipPip
  • 1865 posts
  • LocationBellevue, WASHINGTON

Posted 19 December 2016 - 06:11 PM

Rough my fat ass. I would probably pay for something like that!

 

Possibly going off tangent of the original post though, maybe best to start a new thread? Would be a shame to hide something that is potentially useful on page two in a post with a different topic.

 

You'll have to report your findings. It has been a forever thought of mine would be interesting to see if there is any merit.



#24 grannyknot

grannyknot

    Always Here

  • Members
  • PipPipPipPip
  • 171 posts
  • LocationOntario

Posted 19 December 2016 - 06:20 PM

Thanks SJ, I think you are right, Superduner, didn't mean to hijack.

I'll start another thread.

Chris



#25 superduner

superduner

    Member

  • Members
  • PipPipPipPip
  • 157 posts
  • LocationSAN DIEGO, CALIFORNIA

Posted 20 December 2016 - 04:15 PM

Thanks SJ, I think you are right, Superduner, didn't mean to hijack.
I'll start another thread.
Chris


Haha it's all gravy Chris. Great new thread BTW.
~The Only Person You Should Be Better Than, Is The Person You Were Yesterday.~

#26 mtnickel

mtnickel

    Member

  • Donating Members
  • PipPipPipPip
  • 279 posts
  • LocationSurrey, BC, CANADA

Posted 20 December 2016 - 08:07 PM

The constraint for larger boosters on the 240Z is the space between the throttle pivot bracket and the clutch slave on manual transmissions cars.

 

The larger 280ZX booster fits automatic 240Z cars because there is no clutch MC in the way.

 

I used the 8.5 inch 280Z booster.  See picture for fitment.

 

The 280Z booster bolt pattern differs slightly from the 240Z which requires re-drilling the mounting holes in the firewall.

 

On  SBC V8 with T5 transmission  equipped 240Zs you can to get a little more clearance between the throttle pivot bracket and the clutch slave by using  Wilwood clutch MC instead of the Tilton clutch MC.  The Wilwood clutch MC is much more compact.

 

 

Bro I tried that like crazy and I'll share thst k order to get the zx booster in there BOTH the throttle linkage part Woodhaven to be moved and the clutch MC would also have to be moved about an inch to the right to make room. Still lots the zx booster laying in the garage from the z zxt donor car incase I ever pull the trigger... Although highly unlikely. Unless the 280z booster/15/16 Mc set up feels too much of a pain to stop

 

On the early 260z, I can attest that the 280zx flipped upside down without the spacer does fit just fine (manual car too). Not sure if my firewall/Clutch layout is the same as the 280z, probably. but could also be an early 240, late 240 thing (post 73?).

 

I run the 280zx booster, and the beauty then is that the 300zx (z32) or hardbody (4x4) cylinders fit just fine as well. I grabbed a 1" hardbody Master for like $35 on rockauto that had an arrangement of outputs I liked. I deleted the stock PV (replaced with 2 couplers) and the stock pressure switch. Plumbed in a wilwood knob adjusted PV. Had to make custom lines to go from metric to imperial fittings, but i was making a lot of lines anyways.

 

I was referenced early in this thread regarding apparent Bias with the vented 4x4 setup and 280zx rear (early 280zx, though it's the same piston diameter).

 

For starters, I really like the brake pedal feel I get. I'd say it's a touch firmer than most stock brake systems in your everyday car, but doesn't required excessive effort. Plus I'd rather a firm feel than sponginess. Also, my free play and grab with the 280zx booster and 1"MC is pretty good. There is a tiny bit of movement before it grabs, but I'd say it's less than my fx45 and about the same as my forester XT.

 

Regarding bias, I have still yet to test out bias/locking characteristics in the wet now that the brakes are well bed in. I went with the setup mainly because when I did the math, the 4x4 vented front actually has about the same piston area as the 280zx single piston front brake does. I therefore thought it'd have about the same bias as that car and with a little help from the PV I could get more rear bias. 

 

Car stops very well, but I'd say I haven't driven (or emergency braked rather) enough cars to have a relevant opinion. It also doesn't help the argument considering I have 225ish autocross tires on a 2500lb car, so it's going to stop a lot better than most anything even with a sub optimal bias. For the street, I have no complaints. The pedal feels nice, comes to a halt very fast, and doesn't fade after the 2-4 stops I might make in a spirited drive down some back roads. Plus the looks of my gold painted 4x4 calipers, nicely working E-brake, and easily serviceable rears is a big plus.

 

If down the road I get into more racing and really want to dial in bias, I could look at trying a larger rear rotor and accompanying caliper bracket, or play with pad compounds.

 

 

Also, someone mentioned wilwood PV only goes to 57%. But i was under the impression that with it fully cranked, it was 1:1 ratio and only backing off the spring/knob gives a maximum of ~57% rear bias reduction.

 

Any questions about my setup, just ask!


Edited by mtnickel, 20 December 2016 - 08:09 PM.


#27 Neverdone

Neverdone

    Always Here

  • Members
  • PipPipPipPip
  • 266 posts
  • LocationMilwaukie, OR

Posted 21 December 2016 - 09:19 AM

what brake pads are you currently running?



#28 superduner

superduner

    Member

  • Members
  • PipPipPipPip
  • 157 posts
  • LocationSAN DIEGO, CALIFORNIA

Posted 21 December 2016 - 11:10 AM

On the early 260z, I can attest that the 280zx flipped upside down without the spacer does fit just fine (manual car too). Not sure if my firewall/Clutch layout is the same as the 280z, probably. but could also be an early 240, late 240 thing (post 73?).

I run the 280zx booster, and the beauty then is that the 300zx (z32) or hardbody (4x4) cylinders fit just fine as well. I grabbed a 1" hardbody Master for like $35 on rockauto that had an arrangement of outputs I liked. I deleted the stock PV (replaced with 2 couplers) and the stock pressure switch. Plumbed in a wilwood knob adjusted PV. Had to make custom lines to go from metric to imperial fittings, but i was making a lot of lines anyways.

I was referenced early in this thread regarding apparent Bias with the vented 4x4 setup and 280zx rear (early 280zx, though it's the same piston diameter).

For starters, I really like the brake pedal feel I get. I'd say it's a touch firmer than most stock brake systems in your everyday car, but doesn't required excessive effort. Plus I'd rather a firm feel than sponginess. Also, my free play and grab with the 280zx booster and 1"MC is pretty good. There is a tiny bit of movement before it grabs, but I'd say it's less than my fx45 and about the same as my forester XT.

Regarding bias, I have still yet to test out bias/locking characteristics in the wet now that the brakes are well bed in. I went with the setup mainly because when I did the math, the 4x4 vented front actually has about the same piston area as the 280zx single piston front brake does. I therefore thought it'd have about the same bias as that car and with a little help from the PV I could get more rear bias.

Car stops very well, but I'd say I haven't driven (or emergency braked rather) enough cars to have a relevant opinion. It also doesn't help the argument considering I have 225ish autocross tires on a 2500lb car, so it's going to stop a lot better than most anything even with a sub optimal bias. For the street, I have no complaints. The pedal feels nice, comes to a halt very fast, and doesn't fade after the 2-4 stops I might make in a spirited drive down some back roads. Plus the looks of my gold painted 4x4 calipers, nicely working E-brake, and easily serviceable rears is a big plus.

If down the road I get into more racing and really want to dial in bias, I could look at trying a larger rear rotor and accompanying caliper bracket, or play with pad compounds.


Also, someone mentioned wilwood PV only goes to 57%. But i was under the impression that with it fully cranked, it was 1:1 ratio and only backing off the spring/knob gives a maximum of ~57% rear bias reduction.

Any questions about my setup, just ask!


I Think you're on to Something. I looked up the zx booster upgrade pics on Google and from what it "seems" they look like 260/80z engine bays. Granted they come. With the bigger boosters already I wouldn't be surprised if they also space out the master cyl and throttle linkage system on the firewall some more in comparison to the 240z. If that's the case then us early Z owners got the shorter end of the stick on the design for booster upgrade Hahaha
~The Only Person You Should Be Better Than, Is The Person You Were Yesterday.~

#29 Neverdone

Neverdone

    Always Here

  • Members
  • PipPipPipPip
  • 266 posts
  • LocationMilwaukie, OR

Posted 21 December 2016 - 01:04 PM

Ok, so who out there that owns a 240z would like to play Mythbusters and buy a 280zx booster and see if it fits?



#30 Miles

Miles

    Miles ahead!

  • Donating Members
  • PipPipPipPipPipPip
  • 1820 posts
  • LocationSacramento, CA

Posted 21 December 2016 - 02:22 PM

Ok, so who out there that owns a 240z would like to play Mythbusters and buy a 280zx booster and see if it fits?

 

See post #17 above: The larger 280ZX booster fits automatic 240Z cars because there is no clutch MC in the way.


“Life is like arriving late for a movie, having to figure out what was going on without bothering everybody with a lot of questions, and then being unexpectedly called away before you find out how it ends.”    -Joseph Campbell


#31 Neverdone

Neverdone

    Always Here

  • Members
  • PipPipPipPip
  • 266 posts
  • LocationMilwaukie, OR

Posted 21 December 2016 - 02:37 PM

Ok, so who out there that owns a 240z WITH A MANUAL TRANSMISSION would like to play Mythbusters and buy a 280zx booster and see if it fits?



#32 mtnickel

mtnickel

    Member

  • Donating Members
  • PipPipPipPip
  • 279 posts
  • LocationSurrey, BC, CANADA

Posted 21 December 2016 - 03:41 PM

what brake pads are you currently running?

Centric C-tek Semi-metallic. El cheapo. I had planned to just get them for starters and look for track pads or dual duty, but they have been working nicely that I haven't had the necessity yet. I do plan to attend an autocross event this year, but I think they'd be fine, even for that.



#33 Miles

Miles

    Miles ahead!

  • Donating Members
  • PipPipPipPipPipPip
  • 1820 posts
  • LocationSacramento, CA

Posted 21 December 2016 - 04:42 PM

Ok, so who out there that owns a 240z WITH A MANUAL TRANSMISSION would like to play Mythbusters and buy a 280zx booster and see if it fits?

 

I am the Mythbuster you seek..................

 

I own two 1972 240Zs with SBC 350 and Camaro T5 manual transmissions.  A 280zx booster will not fit on these cars because I tried it. If someone has installed a 280ZX booster on a 240Z configured like mine I would like to know about it  and how it was accomplished.

 

The picture I posted above of the 280Z booster in a 240Z with manual transmission is my car. Note that the 280Z booster fills the available space between the throttle pivot and the clutch MC.

Attached Files


Edited by Miles, 21 December 2016 - 04:45 PM.

“Life is like arriving late for a movie, having to figure out what was going on without bothering everybody with a lot of questions, and then being unexpectedly called away before you find out how it ends.”    -Joseph Campbell


#34 Neverdone

Neverdone

    Always Here

  • Members
  • PipPipPipPip
  • 266 posts
  • LocationMilwaukie, OR

Posted 21 December 2016 - 05:06 PM

Ok, so a 280zx booster will fit a 280z, but not a 240z.

 

And a 280z booster will indeed fit a 240z.

 

Good to know.



#35 superduner

superduner

    Member

  • Members
  • PipPipPipPip
  • 157 posts
  • LocationSAN DIEGO, CALIFORNIA

Posted 21 December 2016 - 05:10 PM

I am the Mythbuster you seek..................

I own two 1972 240Zs with SBC 350 and Camaro T5 manual transmissions. A 280zx booster will not fit on these cars because I tried it. If someone has installed a 280ZX booster on a 240Z configured like mine I would like to know about it and how it was accomplished.

The picture I posted above of the 280Z booster in a 240Z with manual transmission is my car. Note that the 280Z booster fills the available space between the throttle pivot and the clutch MC.


I second that! I got the 280z booster on my 70 240z and the 280z barely fits! I have the 280zxt booster from the donor car laying inside the trailer now because I was unable to fit it in there. From what I noticed. If I wanted to fit the 280zx boost in there we would have to relocate the clutch master cylinder about an inch more towards the driver side fender. Making a new hole in the firewall for the clutch Mc and I'm guessing we'd have to swap out the 240z pedal assemble for a 280z pedal assembly perhaps so the clutch pedal aligns with the relocated clutch MC accordingly. In addition,I'm sure we would have to adjust the boosters shaft length as to make it functional with the MC and not have the brakes lock up, or not engage if too loose. Just a theory I haven't tried but it seems it could work. That big ol booster would definitely be a huge upgrade on pedal feel If we could pull this off.
~The Only Person You Should Be Better Than, Is The Person You Were Yesterday.~

#36 Miles

Miles

    Miles ahead!

  • Donating Members
  • PipPipPipPipPipPip
  • 1820 posts
  • LocationSacramento, CA

Posted 21 December 2016 - 05:30 PM

ditto Superduner  ^ ^ ^

 

I am very happy with my brake setup: Toyota solid front, 240SX rear, 1 inch Wilwood MC, 280Z booster and Axxis Ultra brake pads (good cold bite).

 

The brakes feel like factory and  require very little pedal pressure which was not the case with a stock 240Z booster - 1 inch MC combination. With the stock 240Z booster the pedal was very stiff. Brakes work well in traffic and mountain driving.


“Life is like arriving late for a movie, having to figure out what was going on without bothering everybody with a lot of questions, and then being unexpectedly called away before you find out how it ends.”    -Joseph Campbell


#37 superduner

superduner

    Member

  • Members
  • PipPipPipPip
  • 157 posts
  • LocationSAN DIEGO, CALIFORNIA

Posted 22 December 2016 - 03:55 PM

As far as the proportioning valve goes. I'm looking into the adjustable one for rear; however, I swapped over ALL brake lines from the donor 81zxt on to my 70z and with that came the stock proportion valve on the rear. Would this help out my set up in any way of would I still need to source an adjustable one? Just curiosity to whether or not there's an actual difference between the early z PV and the 280zx
~The Only Person You Should Be Better Than, Is The Person You Were Yesterday.~




0 user(s) are reading this topic

0 members, 0 guests, 0 anonymous users