LS400 front caliper conversion

[SIMON LC]

Anybody interested I have got this complete conversion for sale on the FOR SALE section of the forum.

[garethr]

@garethr: I was looking at LS430 calipers a while back and they are massive, all alloy like you say but they have a strange way of mounting, like a bolt goes straight through it. Do you know how those are mounted?

Sorry, missed this. Sounds as if they are radial mount - the bolts are in line with the disc rather than across.

 

Nightpager sell brackets for the Supra/"UK" discs, but I think they are about 500 quid (+shipping + taxes) at the current exchange rate.

 

EDIT:

Found a pic on the Rockauto web site. They are radial mount.

Edited May 25, 2009 by garethr
Found a pic. (see edit history)

[bigbloodyturbo]

Sorry, missed this. Sounds as if they are radial mount - the bolts are in line with the disc rather than across.

 

Nightpager sell brackets for the Supra/"UK" discs, but I think they are about 500 quid (+shipping + taxes) at the current exchange rate.

 

EDIT:

Found a pic on the Rockauto web site. They are radial mount.

 

Thanks for the info, I think the trouble of fitting them would outweigh the benefits unless you could make your own brackets.

[jonc]

Ok Guys I fitted a pair of Lexus LS400 brakes to the front of my car this week so thought I would add to this thread for anybody who is going to do the same. As the brakes were in bits I decided to do the following (afterall bleeding a Supra brake system is a pain in the arse at the best of times):-

 

1. Refurbish the Lexus front callipers with seal kits from Toyota

2. Refurbish the Supra rear callipers with seal kits from Toyota

3. Fit New Stainless brake hoses replacing the Toyota rubber hoses (I fitted HEL ones this time around).

4. Fitted new brake pads all around.

 

 

To enable a good fit the following changes are needed to the Supra system

1. About 3mm needs shaving off the Lexus calliper web casting next to the top mounting hole. This is already well documented on this thread very easy to do and does not affect anything structural on the calliper.

2. Shorter Lexus mounting bolts are required to mount the callipers (I suppose if you have a lathe then the Supra ones can be shortened)

3. New larger 315mm Lexus brake discs are required.

4. The brake guards need fettling to fit the larger discs and callipers. There is some metal that needs removing and they need bending out slightly to fit the larger discs (some people have removed all together). In the photo the left hand guard has had the metal removed. I then re-sprayed the guards to stop any cut metal rusting.

 

Fitting is really straight forward if 1-4 above have been done:-

 

1. Fitting the fettled guards (4 X M6 bolts)

 

2. Fit the new Lexus 315mm discs. Which just slot over the wheel studs. I held them in place with a couple of wheel nuts until the callipers were fitted.

 

3. Fit the Lexus callipers with the shortened bolts. I also used thread lock on the bolts before torqueing them.

 

4. Fit the new Hoses between the system and the callipers

 

5. Fit the pads and shims.

 

Bleeding the brake system.

 

I use the Gunson easi bleed kit when bleeding brakes. With the Supra I have found the best way to bleed the system is to do the whole system working from the furthest calliper from the master cylinder working you way around the car and finishing at the closest calliper (Nearside rear, Offside rear, Nearside front, Offset rear). Then once the system is bled then start the engine and bleed the same sequence again.

 

Tips which help with brakes.

 

I use compressed air to blow the pistons out of the calliper bodies. Be careful here not to use too much pressure when pushing the pistons and don't get your fingers or any other part of your body between the piston and the calliper when using the compressed air. When the piston starts moving it can come out the calliper at some speed. You can see in the picture I use an old biscuit tin to catch the piston and any fluid which come out.

Cleanliness to a clinical standard is the key when working with brakes.

Soak brake hose flare fittings in penetrating oil and use the correct spanners when disconnecting old brake hoses from the cars brake pipes.

Check and double check fastenings and connections are tight before bleeding/driving.

Always use break fluid from a sealed container (I always use new fluid) as brake fluid is hygroscopic (absorbs water) which can cause issues.

 

 

 

The upgrade has made so much difference to the car under breaking and the one thing I did notice was that the alloy Lexus callipers are half the weight of Supra calliper I removed.

 

Price for the whole project (not including pads):-

 

Second hand Lexus callipers (thanks ruishy1) £80.00

Lexus LS400 315mm OEM Discs £88.78

Lexus calliper seal Kit from Toyota £36.00

Supra rear calliper seal kit from Toyota £36.00

Lexus calliper bolts from Toyota £7.39

New brake fluid£5.00

HEL Brake hose kit£69.00

Total Cost for system overhaul and upgrade £322.17

 

the finished article looks like Toyota meant to fit them

I have to say that if anybody is contemplating a brake upgrade then the Lexus LS400 brakes seem to do the job. I don't do track days in the car which is why I fitted OEM discs and from an engineering perspective I'm not sure how the forces differ to the UK brakes but the price is a lot less than using UK brakes, The parts are all available from Toyota and the difference can only be minimal (surface area etc etc). If anybody needs further advice I would only be too happy to help.

Edited August 26, 2011 by jonc (see edit history)

[scotty71]

good write up there mate. I have always wanted to go down the LS400 route

[Swampy442]

Just to make a point here, UK spec calipers go straight on and you dont need to grind bits off the calipers. I just dont understand why people do this.

[jackso11]

because it is a hell of a lot cheaper....

[jonc]

Just to make a point here, UK spec calipers go straight on and you dont need to grind bits off the calipers. I just dont understand why people do this.

 

I agree the UK's fit straight on (Do the stone guards need any adjustments?) and I know you have questioned the grinding of calipers before but Honestly the amount of material you take away is tiny on the web and it makes no difference to the structure of the caliper. I did not use a grinder I used a small file and it took a couple of minutes.As a qualified mechanical technician with 25 years experiance myself I do nothing to compromise the safety of the equipment I work on/with (Especially my cars!!!).

 

because it is a hell of a lot cheaper....

 

That why this upgrade is conducted by some. I am lucky enough to have 3 cars on the road so budget has to be a factor to keep them all running, although I always use OEM parts where possible . If I had just done the front upgrade and nothing else the cost would have been about £220 all in. It would be interesting to know the actual difference in stopping power between the UK set up and the Lexus brakes as the dimension are very similar (Master cylinders,discs and pistons). The other startling thing is the difference in weight between the callipers. The ally callipers I fitted are half the weight of the JSPEC callipers and the UK ones must be heavier again and lets face it these calipers were designed to stop a heavy 1725KG car and the Supra is what? about 1600kg so there is more than enough force from these calipers to give you a good standard of upgrade.

 

Anyway each to their own, I did this upgrade after doing a lot of reading about it on here and the American/Australian sites and I am completely happy with the results .

[Scott]

Stone guards need hacked off regardless of what option you take

[jackso11]

can you get UK stone guards and swap them?

[Scott]

can you get UK stone guards and swap them?

 

Yes but it's a PITA of a job. One of the axles is harder than the other and requires the whole hub to come off.

[jackso11]

Well, that means not possible in my books

[dr_jekyll]

i did it because the lexus are a lot lighter than the uks. and alot cheaper.. and every bit as good at stoping the car... and its not major surgery to get them on , you have to fun a file over a few mm of the caliper for 30 seconds .

 

i cant see why people wouldnt use these over the uks

[Graham S]

Just a quick one, jonc, great write up but just one thing! Near the end you put that you used compressed air to blow the pistons out! You might wanna put a bit in there about not putting fingers inbetween the piston and the caliper! I've known someone to do that and it pretty much broke their fingers when the piston shot out!

 

Sorry not meaning to critisize, just trying to help others.

[Scott]

i did it because the lexus are a lot lighter than the uks. and alot cheaper.. and every bit as good at stoping the car... and its not major surgery to get them on , you have to fun a file over a few mm of the caliper for 30 seconds .

 

i cant see why people wouldnt use these over the uks

 

They aren't as good though. In fact I seem to remember you commenting that they weren't as good due to having UKs on the back and the car trying to turn on you under heavy breaking.

[scotty71]

Im after bigger fronts and will go for the LS400's I thinks

[dr_jekyll]

They aren't as good though. In fact I seem to remember you commenting that they weren't as good due to having UKs on the back and the car trying to turn on you under heavy breaking.

 

i thaught it was because as the uk rears but it still does that . im thinking its suspesion /weight distribution related now

 

ive recntly had 2 supra with uk set up in and my car will outstop both of them . even if its a bit snakey in doing so. though my car is a fair bit lighter than both and on CW pads so hard to do a direct comparison but the bite is no better on the uks

Edited August 26, 2011 by dr_jekyll (see edit history)

[dr_jekyll]

double post

[jonc]

Just a quick one, jonc, great write up but just one thing! Near the end you put that you used compressed air to blow the pistons out! You might wanna put a bit in there about not putting fingers inbetween the piston and the caliper! I've known someone to do that and it pretty much broke their fingers when the piston shot out!

 

Sorry not meaning to critisize, just trying to help others.

 

Thats a really good point Graham, Thanks for pointing it out. I will edit the post as the last thing you need to do is put 30-40 psi up the rear of the caliper and try and stop the pistons with your fingers when it goes pop:eek:. I'm always open to constructive critism it's how we learn in life and no one is perfect

[garethr]

Can you get UK stone guards and swap them?

You would have to remove the hubs to do the rears, but the fronts are easy http://planetsoarer.com/suprabrakesII/SupraBrakeUpgrade.htm

 

Cut a section out to remove and replace them (as in jonc's post in this thread):

 

 

Edited August 27, 2011 by garethr (see edit history)

[Guest Skullface]

I've got two 1998 LS400's, with this ally 4pot, just to clarify something mentioned above, the wet weight is not 1725kg, my vin plate state 2250kg. The Mk4 98> model weighed a fair lump more, hence the mad calipers, especially with a limited top of 155mph. In perspective, you could put a half tonne in the boot before a supra even came close to the force these are designed to stop.

[Herb]

sounds interesting...

[bigbloodyturbo]

I've got two 1998 LS400's, with this ally 4pot, just to clarify something mentioned above, the wet weight is not 1725kg, my vin plate state 2250kg. The Mk4 98> model weighed a fair lump more, hence the mad calipers, especially with a limited top of 155mph. In perspective, you could put a half tonne in the boot before a supra even came close to the force these are designed to stop.

 

Ls400's are nowhere near as fast as tt supra's though. I have these xalipers and they were really good however I wouldn't say they were better, I believe it has already been proven that they have slightly less stopping power than uk's

[garethr]

Everything else being equal (pad material, disc material, master cylinder, driver, tyres) the variables are the caliper piston area (one side of the caliper only), and the effective diameter of the disc (without a load of maths, call it the middle of the pad), so 4-opposed piston calipers are not necessarily any more powerful than 2-piston sliding calipers.

 

The dimensions I have are:

J-spec - Piston Diameter 44.4mm / Disc Diameter 296mm

LS400 - Piston Diameter 42.8mm or 43.0mm (sources differ) / Disc Diameter 315mm

UK Piston Diameter - 42.8mm / Disc Diameter 323mm

 

There is a kit for the Lexius IS300 (same calipers as J-Spec) that spaces the calipers out to fit a UK disc. I suppose that would, theoretically, be "better" than UK brakes.

 

 

http://www.mkivsupra.net/vbb/showthread.php?225007-Big-Brake-Kits-Real-Numbers

Edited January 29, 2012 by garethr (see edit history)

[Guest Skullface]

Ls400's are nowhere near as fast as tt supra's though. I have these xalipers and they were really good however I wouldn't say they were better, I believe it has already been proven that they have slightly less stopping power than uk's

 

Quite so, I wasn't suggesting LS calipers should upgrade TT's, just reassuring that anyone using an LS caliper on a NA Supra was well within spec.

 

And a LS400 is just as fast as a Supra... its the speed the vehicle is breaking from that heats the discs not the acceleration that got it there.. both are limited to 155mph. of course, I'm only generalising. racing on a track would be different.