80 Series Booster on a Turbo Hilux - heat problem?

[whiteknight]

I had my calipers rebuilt last week and I finally have brakes again

What I want to know is - is it worth while fitting the 80 series booster and MC up with the standard hilux dual piston calipers? What will be the benefits or am i wasting my time without the 80series calipers to go with it.

[whiteknight]

No-one knows?

What I thought was that if i do this I will have a better brake pedal as more pressure will be in the system or have i got it all wrong and it wont do jack without the bigger pistoned calipers to go with it.

[jugger]

A mate of mine sayed that u need the later model booster and master . apparently its 11/2 inch bore and the earlyer ones are only 1 inche . but this is second hand and weve had a few rums since then.

[whiteknight]

The booster is from a 96 model 80 series. that late enough?

[slosh]

80 series M/C has 1" bore, whereas your hilux one is 15/16" I think. Fitting up the bigger M/C will mean you will have very small pedal stroke because more fluid is being pumped into the pistons earlier. So unless you have a long pedal stroke now, you may find locking up the brakes to be a problem with this mod.
Also the 80 M/C is designed for rear discs (unless you get the early one- I think base model 80's pre 93 were drum rear don't quote me) so you may have to get adjustable proportion valve to get the correct bias back again with the Hilux drums.
The v6 4runner M/C would be a better choice anyhow. (1" bore and valved for rear drums)
I would stick with the std setup until you change to bigger calipers or rear discs.
You can change just the booster to the 80 it's all bolt on may give nicer pedal feel.

[Ruffy]

You have to calculate the surface area of the piston in the master versus the piston in the caliper. Small master cyl bore and large caliper piston means heaps of pressure but longer travel. Larger master cylinder bore will reduce the pressure that it supplies for the same effort on the pedal. In other words your pedal wont travel as far and you'll have to press harder to to get the same braking performance. As for the booster the 80 series one will help with the pedal effort but i wouldn'r guaruntee it will be as good. Caliper upgrade is going to give you best results

[whiteknight]

Well bit the bullet and put on the 80 Series master and booster.

The pedal only moves about 2 inches now and pulls up on a dime - glad i did this !

Although I had to remove the heat sheild from the turbo so that the brake lines could fit into the booster properly - From the pics do you think it will be alright or should I try and put some heat shielding in there somewhere? And if so what to use?

[LuxyBoy]

Have you jacked up your rear to see if it stops the rears well enough or aswell as the fronts?

[whiteknight]

Have you jacked up your rear to see if it stops the rears well enough or aswell as the fronts?

Jacked up the rears?

It pulls up real nice no skidding from the rear if this is what you are trying to ask although will have to wait until its wet for another test but its easy as bending the brake bias line on the back diff a bit to compensate..

[+dj_hansen+]

Did u just source the bits from a wrecker? What sort of $$ all up for the calipers and 80 M/C?

[whiteknight]

Did u just source the bits from a wrecker? What sort of $$ all up for the calipers and 80 M/C?

Yeah wrecker supplied the parts - Booster and MC around $130 from memory - Got charges $60 to get it all fitted up including new brake lines etc and they said they had to extend a linkage to get it to work.

I didn't upgrade the calipers as my model hilux already has the 4 piston type and i couldn't see the benfit in spending the $$ for an extra 5 or 6 mm piston size.