ben,

how have you found the weight of the calipers? have heard they kill the handling?

Dave

_________________
USA Daily: 2014 Nissan GT-R, very minor modifications for the track
USA Project: 1978 280Z, minor suspension upgrades, VK56DE conversion in progress. SOLD
AUS Race Car: 1973 240Z, L28ET, Autronic, GT35R. SOLD
AUS Project: 1972 1600, 3200km old S15 SR20DET, ground up rebuild. SOLD

Consider it offset by the lighter alloy wheels....
Seriously, the cast OEM calipers are only about 1kg lighter than the cast 4-spots, so yes it's extra, but not much.
I've been running the 'lux calipers on my Z since 1997, and the bias was pretty good when used with the OEM drum rear. Stopping power was noticably improved over the OEM brakes (which were in pretty good nick), with only a little more pedal travel. But when I fitted the disc rear end, the bias went to the shitter & the pedal travel was worse. The pedal got even worse when I adjusted the bias up on the brake rollers at the Regency Park Inspection centre (for roadworthiness due to my L28ET conversion). It passed the brake test, but I wasn't happy with the feel. One week later I'd fitted a 1" master & now they are sweet (firm, but not rock hard).

I will upgrade to R32/33 brakes on the front in the near future, which will deal with the 'unsprung weight issue' and further increase the braking power.

Having said that, a 1" master with R30 brakes (disc/disc) fitted to a 180B is far too hard, and a 15/16 gives a more usable pedal.

A 15/16 gives a nice pedal when used with the R31/R31 combo too, 7/8 is too soft.

_________________
Ben
Adelaide,
South Australia
L28ET 240Z
RB25DET WGNC34 Stagea RS-FourV

So hilux calipers with stock discs and unchanged master cylinder was still reasonable? Sounds like a plan. Where do you get 1" master cylinders from if I may ask such an obvious sounding question.

Dave

_________________
USA Daily: 2014 Nissan GT-R, very minor modifications for the track
USA Project: 1978 280Z, minor suspension upgrades, VK56DE conversion in progress. SOLD
AUS Race Car: 1973 240Z, L28ET, Autronic, GT35R. SOLD
AUS Project: 1972 1600, 3200km old S15 SR20DET, ground up rebuild. SOLD

So going from a 7/8 to a 15/16 would make a big difference to pedal feel??

So by yuk you mean pedal feel and not braking performance?? So the car would pull up better and have a more progressive feel if I went to 15/16 ??

Would I need a bias valve by putting r31 discs on the back using the Lux callipers on front??

Cheers

Justin

Dave - Yes that's a plan, and a cheap plan at that. The 1" MC is from a Patrol, part number JB1419. Don't forget to remove the residual valve from the rear circuit if you do a disc upgrade.
The pedal is noticably firmer (more than 1/14 of an increase would lead you to believe). With a 7/8 the pedal was much lower, and as a result the braking power was less. Suck it & see with the MC size - try a 7/8 & if it's not to your likeing, upgrade.
I recommend the use of a bias valve, but be careful where you put it - the authorities don't like them in the cabin on a road car.

_________________
Ben
Adelaide,
South Australia
L28ET 240Z
RB25DET WGNC34 Stagea RS-FourV

Flawless,

With regards to fitting a bias valve in the front line, I actually mean braking performance and not feel!

Technically speaking, fitting a bias valve in the rear line should be a good thing in most cases. Fitting a bias valve in the front line is a poor bandage for your circumstances, and a bad idea for everyone else!

I can try and explain why that is, but it's a bit involved. Basically, a bias valve has side effects that practically everyone seems to be unaware of. They do not effect the brake bias at a constant rate. This has it's advantages and disadvantages!!

Have a look through the tilton catalogue (downloadable PDF at tilton.com), and that explains how they work. It also explains (a bit too briefly) why they are a good idea for rear lines in a street car.

If you want any more clarification on that, I can try!!

G'day, i'm looking into doing this conversion on some 240K struts, and was wondering if someone could tell me what discs need to be used? i want to use vented rotors too if possible. also does it matter which 240k struts i have? anything else need to be changed besides discs/calipers, as i've read lots of conflicting info on different forums etc and now i'm just confused.
thanks,
dave

_________________
Dave W

The 1600

Recommended traders: Nissanman, pro240c, 2door510, Datsport, mkyle, Green510, Um_510, jdmdatsun510, Ludachris

Magna verada - DBA425 part number.

My brother-in-law just did the conversion on his 240k struts, got second hand rotors from pick n pay $60, redrilled to 4 stud $50, calipers were $60 bucks also.

A few washers to space them over the caliper, and a small bit of grinding inside the caliper and they were on.

Dave,

There are 2 different struts commonly fitted to the 240K. The most reliable way to tell them apart is to measure the disc diameter. One has a 10" disc (253mm) and the other has the 11" disc (about 277mm).

The "big disc" strut has the caliper mounting lugs further out from the hub, to accommodate the bigger disc. This is the strut you want, as you will always get a bigger disc under the caliper (assuming you're bolting a standard 3.5" bolt spacing caliper directly to the strut, eg Hilux / Landcruiser)

The 253mm disc strut was commonly fitted with the twin opposing piston Sumitomo caliper, which seems to be the preferred option for non ventilated discs. These aren't as bulky as the "single" piston caliper so will generally fit under a smaller wheel. However, the calipers are interchangeable, so don't judge the strut by the caliper it's wearing.
Whoa there! Sounds easy when you say it like that. Remember, these are brakes we're talking about. If you need to space anything out, use proper FLAT shim that covers the whole contact area between the caliper and strut. If you don't know what you're doing, then at least get an expert to show you how it's done.

He did use shims, please excuse my wording, its not rocket science, as long as the caliper is centred over the disc...

He measured them with verniers on either side and end to make sure they were sitting straight.

Just found a pic, looks like he spaced the rotor out, not the caliper...