Need advice/opinions on hilux brake upgrade

[old_school_jap1]

Hello everyone, I am up to upgrading the braking system on my rn16 hilux, for those of you that don't know that is the 1st gen hilux. Anyways, it currently has 230mm drums on every corner and no brake booster, as it did from the factory. I want to go to peugeot rotors and landcruiser 4 piston calipers on the front and ma70 disks and calipers on the rear. I have found a master cylinder that will bolt up in the standard holes, it's an AE101 super strut, anyone know the bore of this mc??? I have looked into getting a booster from another car working on it, but the clutch master cylinder is too close to the brake master as is and I need the room for sidedraught carbs . Will the setup that i want to go to be dangerous without a booster? Any advice and opinions will be greatly appreciated

[old_school_jap1]

c'mon peoples, need to know if i'll have a problem before i start buying stuff

[The Real Roadrunner]

the MA70 rear setup works well but im not sure that you would be able to adapt the pug rotors to the front ( would need to check many measurements).

Un-boosted is fine so long as you have sized the maso correctly and have set the pedal ratio up correctly, (once again many measurements and calcs needed)

Id like to be able to give you a yes/no answer but unfortunately it would consume 4+hrs in researching to figure it out and i don't have the time.

Cheers
Linden

[old_school_jap1]

i've already got the hilux/peugeot setup sorted, by using sr5 rn4_ hilux disc brake spindles. they have the twin piston brakes like rt13_ ronas and the 4 pistons bolt up in their place. the sr5 standard rotor is also very close to the peugeot rotor, i've done all the calcs on that and it should work.

from reading a few booster or no booster threads on toymods, my understanding is that it's all about the leverage of the pedal, am i correct? it's just a big leap from 230mm drums all round to 4 pistons on the front and big rotors on the back. is there any way you could teach me a simple way to work out if it'll be right (ie. pedal leverage or some such)?

[The Real Roadrunner]

if you do a google search on pedal ratio it should bring up some interesting stuff for you to read. factory cars seem to run about 5:1 but un boosted needs about 7:1 from memory (id have to double check.

Then you need to figure out how much rod travel this will give and size your maso to suit. aswell as making sure the bias will end up correct.

Hence the may calcs involved.

It can be very hit and miss and unfortunately there is no quick and dirty way to figure it all out.

i think the stoptech site had some good info in it from memory.

[old_school_jap1]

reckon a 7/8" master (finally found out that that is what the ae101 superslut master is) would be useable with that brake combo?

[thechuckster]

given that 4-spots fronts + twin or single-spot rears (admittedly on an MA61 or RA23/28/40) tend to do well with a 15/16" MC, I'd suggest the same ... but that's just a wild guess.

[LT1986]

...most people seem to use the starion master cylinder though and go the full 1 inch bore though...i believe your hilux has the same booster unit from RA23's ect and so its a direct fit...could be wrong however

[old_school_jap1]

i believe your hilux has the same booster unit from RA23's ect and so its a direct fit...could be wrong however

that's the main reason i put up a thread, as this is the only model of hilux that doesn't have a booster from the factory and was worried about safety. the brake master on it standard is a 3bolt, that's why i'm looking at the ae101 superslut one.

[LT1986]

sorry, missed that bit...good old toyota changing things for the sheer giggle of it, will the booster be okay going from a 4 wheel drum to a 4-wheel disc configuration? im not sure on the load differences between the two but i as i understood it drums used about 30-40% less hydraulic fluid than an equivalent disc setup, add to that a nearly 35 year old brake booster and it could be problematic to pedal feel and pressure...would it maybe be easier to swap the entire booster/MC for something a little more modern, even if it is the RA/starion setup?

food for thought

[thechuckster]

swapping booster might/would also require change to the pushrod from medal to booster, plus the bolt pattern on the firewall.

However, as Linden suggests, the pedal leverage will have to change anyway.

[old_school_jap1]

sidedraft carbage takes priority over brake boosterage . plus i don't wanna have to stuff around with the pushrod and all that. i will take some measurements of the pedal and standard master cylinder and get back to yous. thanks for the help

[wagonist]

You can always remote booster it if need be.
Maybe mounted behind one of the headlights (I'm not sure how tight your engine bay is).

I'd be trying to find a bigger master than 7/8"
When I did the brake upgrade on my last Caldina, I went from single piston front calipers & rear drums to 4 spot fronts & single piston rear discs, the brake balance was never quite right & the feel just wasn't there properly.

[thechuckster]

personally, i'd just upgrade the MC to a MA61 or MZ10 item (both are 15/16") and leave it at that.

[o_man_ra23]

+1 for remote booster. Also +1 for 7/8" won't be big enough. There is a lot of piston area to be moved and you would be flat out doing that with a 7/8". 15/16" would provide a far better solution, 1" may or may not become overkill. Can you change the bolt pattern for the firewall?? Bit of metal fabrication, bit of reinforcing, new studs, and Bob's ya aunty.