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The mkiv Supra Owners Club

JSpec / UK Spec brakes


Noz

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This is probably a well known fact, but still id like to ask..

 

I only hear people talk about the jspec or UK spec brakes, so am I correct in assuming the jspec NA and TT have the same brake set up?

 

Hope this isnt a `dumb` question.

 

Thanks :)

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There is no such thing as a 'dumb question' there are however 'dumb people' :) better to ask the question and look like a fool for 5 minutes than not ask and look like a fool for a lifetime...... I think thats all the quotes I have on this subject :)

 

I'd not really thought about it, I always assumed they were the same.

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Some J-Specs came with larger brakes, i'm not sure whether they were standard on some later models or just an optional extra. They are only called UK Specs as that was that was standard on all models in the UK. So it's more accurate just saying smaller/larger or 2pot front 1pot rear/4pot front 2pot rear.

 

It does mean that some NA and TTs came with the same brake set up though.

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J spec n/a and TT had 2 piston sliding type calipers up front and one piston sliding type at the rear. The front discs were larger up front on the TT.

 

Export spec or UK spec brakes were 4 piston opposed type up front and 2 piston opposed at the rear

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J spec n/a and TT had 2 piston sliding type calipers up front and one piston sliding type at the rear.

 

There were many NA and TT J-spec Supras that were factory fitted with the larger 4pot/2pot brakes (in fact there were more J-spec Supras fitted with the larger brakes as standard than the total number of UK spec Supras produced.)

 

The front discs were larger up front on the TT.

 

Don't really understand this? The larger brakes have bigger diameter discs, the smaller brakes have smaller diameter discs, it doesn't matter which Supra model they were fitted to. The rear discs are a slightly bigger diameter than the fronts, although they are narrower on the rear.

 

The term 'UK spec brakes' is confusing. The Supra (all models) came with 2 brake options; the smaller 2pot/1pot brakes and the larger 4pot/2pot brakes, J-spec Supras were fitted with both brake types depending on the model and year, ALL UK spec Supras were fitted with the larger brakes.

 

Smaller spec brakes

2 pot front calipers - 296mm diameter discs

1 pot rear calipers - 307mm diameter discs

 

Larger spec brakes

4 pot front calipers - 323mm diameter discs

2 pot rear calipers - 324mm diameter discs

Edited by Nic (see edit history)
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There is no such thing as a 'dumb question' there are however 'dumb people' :) better to ask the question and look like a fool for 5 minutes than not ask and look like a fool for a lifetime...... I think thats all the quotes I have on this subject :)

 

Look at the "Boot Release" thread and retract your statement :p

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There were many NA and TT J-spec Supras that were factory fitted with the larger 4pot/2pot brakes (in fact there were more J-spec Supras fitted with the larger brakes as standard than the total number of UK spec Supras produced.)

 

 

 

Don't really under stand this? The larger brakes have bigger diameter discs, the smaller brakes have smaller diameter discs, it doesn't matter which Supra model they were fitted to.

 

The term 'UK spec brakes' is confusing. The Supra (all models) came with 2 brake options; the smaller 2pot/1pot brakes and the larger 4pot/2pot brakes, J-spec Supras were fitted with both brake types depending on the model and year, ALL UK spec Supras were fitted with the larger brakes.

 

Smaller spec brakes

2 pot front calipers - 296mm diameter discs

1 pot rear calipers - 307mm diameter discs

 

Larger spec brakes

4 pot front calipers - 323mm diameter discs

2 pot rear calipers - 324mm diameter discs

 

:yeahthat:

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im unsure which set mine are, il need to check. would the ksport 330mm 8 pots be that much better than the large 4 pot 323mm? only 7mm extra width, i know there are another 4 pots in the caliper would this make a big difference?

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Its mainly to do with cooling in my opinion. You can only get so much pressure down the brake pipe, the surface area of the pad on the disc obviously makes a difference but not a great amount. less pots=less fluid in the caliper making it prone to boiling. its all about dissipating heat. This is only my opinion.

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im unsure which set mine are, il need to check. would the ksport 330mm 8 pots be that much better than the large 4 pot 323mm? only 7mm extra width, i know there are another 4 pots in the caliper would this make a big difference?

 

Post up some pics of the calipers so we can identify which they are.

 

If you have the larger Supra brakes, with a good set of pads, braided lines and decent fluid they are more than up to any fast road and track day use. I would choose the larger stock brakes over the K-Sport brakes.

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The term 'UK spec brakes' is confusing. The Supra (all models) came with 2 brake options; the smaller 2pot/1pot brakes and the larger 4pot/2pot brakes, J-spec Supras were fitted with both brake types depending on the model and year, ALL UK spec Supras were fitted with the larger brakes.

 

:yeahthat: I almost wrote something identical :thumbs:

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Its mainly to do with cooling in my opinion. You can only get so much pressure down the brake pipe, the surface area of the pad on the disc obviously makes a difference but not a great amount. less pots=less fluid in the caliper making it prone to boiling. its all about dissipating heat. This is only my opinion.

 

Chris Wilson has a good article on brakes posted on the forum, try and search for that.

 

Regarding the number of POTs and heat - the UK POTS are huge compared to most of the aftermarket ones so dont think its necessarily just about the volume of fluid in the calipers.

 

Not to mention that the UK ones are not alloy and hence "should" be better able to withstand abuse on track without flex.

 

Extra number of pistons have been reported to give better feel and initial bite (perhaps) - however does nothing to help the stopping power (another usual misconception).

 

imi

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ThereSmaller spec brakes

2 pot front calipers - 296mm diameter discs

1 pot rear calipers - 307mm diameter discs

 

So the n/a Supra didnt come with 276mm discs or whatever they are? My understanding was the n/a J spec cars has smaller discs, the TT J spec cars had bigger discs then the 'UK specs' had the 323mm discs.

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So the n/a Supra didnt come with 276mm discs or whatever they are? My understanding was the n/a J spec cars has smaller discs, the TT J spec cars had bigger discs then the 'UK specs' had the 323mm discs.

 

Nic's post covered this accurately

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I will have a set of UK's for sale soon mate ;)

 

Time for my occasional friendly reminder that, unless specifically asked by the OP for quotes/offers, please don't pimp your wares in tech :) This became a bit of an unwritten rule after the turbofit idiots poisoned tech discussions with sales pitches at every opportunity. Fanks :D

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Guest ayresyboy

hi guys, newbie here. i have supra brakes on the front of my mr2 but unsure which ones. piccy below...

 

image

 

i think they are these...

 

http://www.japandirectjapanese.com/product.php?productid=303&cat=34&page=1

 

both fronts need to be reconditioned. i have been quoted £379 to get this done. fair price? is it possible i could buy an already recondition pair for less than that? if so where from?

 

thanks in advance

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hi guys, newbie here. i have supra brakes on the front of my mr2 but unsure which ones. piccy below...

 

http://i875.photobucket.com/albums/ab312/ayresyboy/Picture129-1.jpg

 

i think they are these...

 

 

http://www.japandirectjapanese.com/product.php?productid=303&cat=34&page=1

 

both fronts need to be reconditioned. i have been quoted £379 to get this done. fair price? is it possible i could buy an already recondition pair for less than that? if so where from?

 

thanks in advance

 

There's a chance they could be Celica GT4 calipers, but probably they

 

are off a MKIV Supra.

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