Disc swap, which brake booster to use with master cylinder?

Discussion in 'Suspension/Chassis' started by CodyX36, Jun 24, 2014.

  1. CodyX36

    CodyX36 Enthusiast

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    Location:
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    '72 RN14
    Running into some problems, I have everything I need from a '76 to swap over on my '72, all the brake components are bolted up, have all the brake lines in place, but having trouble with booster and master. '76 master won't bolt up to '72 booster because bolt pattern was changed. The booster from the '76 is about twice as large as the stock one, so unless I move the slave cylinder a few inches, it's not going to fit, which I am trying not to do if needed. I read one guy on here used the front plate of a booster from a '74 Celica with the stock backing plate, but would the power be much of a difference? Also, that the '81+ 2WD boosters are smaller, but small enough to fit without needing to move anything else? Thanks for anyone who can help me out here.
     
  2. jwtlake

    jwtlake Newbie

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    I'm just about to do the same with in my 1970 using 1978 parts. I think i have everything but the proportion valve and the booster stuff. Rock-auto parts have been trickling in all week.

    So many refrigerator magnets!! haha

    I'll let you if i figure out anything but I'm thinking you might be a few steps ahead of me at this point. Good luck!
     
  3. CodyX36

    CodyX36 Enthusiast

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    I think I found a booster that works, a Toyota enthusiast that lives in the area looked though his pile of parts and pulled this one out, said he wasn't 100% sure what it was from, but the firewall-side studs are exactly the same, and it has the 2-bolt pattern on front for the 2nd gen master cylinder I have. The size of the booster is smaller and almost identical to the stock booster from the Hilux. I won't be able to match it up until next weekend, but it seems like this will work. It has 2 numbers on the booster, "44610-3022" and "2L11463". Both aren't Toyota part numbers, but after some research, the "44610-3022" number is similar to "51300-60B20". Turns out the booster isn't from a Toyota at all, but is from a Geo Metro/Chevy Sprint/Suzuki Cultus, weird. Some pictures below of the booster with the 2nd gen Hilux master cylinder. I'll give an update with pictures hopefully within the next couple weeks when I can get to the shop to fit this on!

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    Last edited: Jun 29, 2014
  4. NotAvailable

    NotAvailable Addict

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    Some guys run the adapter plates and re compensate from the pedal adjustment.
     
  5. jwtlake

    jwtlake Newbie

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    How did the insides match up? (Between the booster and the master cylinder) I was at the yard today and pulled one out of a 92 geo metro. It seems allot different on the insides then I'm used to. The plunger on the booster seems really recessed and the master cylinder actually goes inside the booster quite a ways. Is that the same way the second gens toyotas work?
     
  6. blueline54

    blueline54 Member

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    Did anyone get the booster from the GEO Metro to work? Looks like I'll need to enlarge the hole through the firewall to get it to bolt up, and was hoping for some feedback before I went that far.
     
  7. blueline54

    blueline54 Member

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    @jwtlake, looks like you'll need the master cylinder from the Geo as well. Take a look at it on Rockauto and you'll see the difference.
     
  8. jwtlake

    jwtlake Newbie

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    CodyX36 was actually the one who made this discovery and has the booster. I just looked at one when I was at the wrecking yard.
     
  9. CodyX36

    CodyX36 Enthusiast

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    Not sure how insides matched up, seems like they go together fine though. I haven't ran it yet since my motor swap isn't done, but I guess I'll find out how powerful it is. Like I said, I'm not 100% sure what vehicle this one is from, by the part number though is how I tracked down that they were put in Geo Metros. Just needed a small one with the 2-bolt pattern to line up to the 2nd gen Hilux ones. These boosters sat closer to the firewall in the original car, so I had to trim a little off the lip part on the firewall for it to fit around and be pushed far enough back. I have a slight picture of it, but not the greatest, I'll get some more photos next weekend when I go to work on my truck.

    [​IMG]
     
  10. jwtlake

    jwtlake Newbie

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    Oh man that looks sick!
     
  11. Brennan

    Brennan Newbie

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    Hi wondering if you got this to work and Would be down to share some photos with me I just bought a Geo Metro booster for my 70 hilux disc swap
     
  12. Brennan

    Brennan Newbie

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    Location:
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    Hey would you be down to send me those pictures again? Just got a metro booster for my swap. Thanks!
     
  13. David Eidson

    David Eidson Member

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    Swapping a '76 brake booster onto a '72 with a different bolt pattern poses challenges. The '74 Celica front plate with the stock backing plate may work, but power differences can occur. Consider adapting an '81+ 2WD booster, known to be smaller, potentially fitting without major adjustments. Confirm compatibility by comparing dimensions and checking forums for similar swaps. Test-fit or consult with experienced hobbyists for insights on maintaining optimal braking performance. While adjustments might be necessary, prioritize safety and ensure the brake system functions effectively after the modification.
     

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