Celica ST165 calipers under 15" wheels?

Discussion and technical advice for 84-89 AW10 & AW11 MR2. 3A-LU, 4A-GE, 4A-GZE.

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Adam W
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Joined: Tue Jun 17, 2008 12:30 pm
Location: North Herts

Celica ST165 calipers under 15" wheels?

Post by Adam W »

Seeing as I need new discs, pads, and a caliper refurb on my car, I figure it would not cost a lot extra to do a brake upgrade. The ST205 caliper swap is detailed pretty thoroughly on the web but I don't want to fit 17" wheels, they're a bit OTT for me and I get through a lot of rear tyres which would get expensive on 17's!

I found an online spreadsheet which shows that the ST165 twin piston calipers bolt on OK, and you just need to redrill the discs for four-stud fitment. I wondered if anyone on here had done it, and whether the brakes will fit OK under 15" wheels?

I realise not all 15" wheels offer the same amount of0 brake clearance - the wheels on the car at the moment are made by 100+, I will have to check the offset etc tonight.
MartG
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Re: Celica ST165 calipers under 15" wheels?

Post by MartG »

The ST165 twin pots fit under the standard 14" wheels, never mind 15" ones, and use the standard MR2 disk


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cartledge_uk
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Re: Celica ST165 calipers under 15" wheels?

Post by cartledge_uk »

The corolla levin calipers also are a straight fit and use the same discs you can either have a twin pot or a huge single pot, interestingly enough, in the USA they prefer the singles as you get better feel and power.

will try and get pics of the aw11 to levin caliper tonight.
Tom G
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Re: Celica ST165 calipers under 15" wheels?

Post by Tom G »

although it's fun bolting on big calipers, take a second to consider WHY they might improve braking performance....
> Std mk1 discs used
> more piston area means more front bias (i.e. for a front engined celica)
> more piston area means squishy brake pedal
> bigger pads mean more front bias

more front bias is effectively the same thing as less rear bias. With your front brakes doing all the work, they'll fade faster and lock up more easily.

However, if you still want them, you're welcome to buy mine, complete with nearly new redstuff pads :)
Adam W
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Re: Celica ST165 calipers under 15" wheels?

Post by Adam W »

I intend to upgrade the rears as well, and maybe get a different master cylinder to retain brake pedal feel. All very valid points though! I just felt that the stasdnard brakes (even on my shoert test drive) were so bad that I had to make a change. Have PM'd you about your calipers!
cartledge_uk
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Re: Celica ST165 calipers under 15" wheels?

Post by cartledge_uk »

Adam W wrote:I intend to upgrade the rears as well, and maybe get a different master cylinder to retain brake pedal feel. All very valid points though! I just felt that the stasdnard brakes (even on my shoert test drive) were so bad that I had to make a change. Have PM'd you about your calipers!


If the std brakes feel rubbish, try braided hoses, change the fluid and check the calipers and pistons move freely
LimeyMk1
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Re: Celica ST165 calipers under 15" wheels?

Post by LimeyMk1 »

I think practically every Mk1 out there will be in need of a full caliper refurb.

Before you splash the cash Adam remove your calipers and carriers and clean them up. If needed change the seals/boots, free up the sliders and clean up the pistons.

Your pads should fit fairly easily into the carriers, if they don't take the carrier off and tap it with a hammer. You'll be amazed at the crud that'll fall off.

Look at Max's Knowledge base article, it covers the whole thing really well.
Adam W
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Re: Celica ST165 calipers under 15" wheels?

Post by Adam W »

Yeah, the standard brakes are FUBAR, but after working out the costs for a proper refurb kit, new standard sized pads, discs, etc, it only works out around 25% more expensive to go for bigger calipers all round. I drive pretty hard, so I would rather spend the money now, than refurb the standard brakes, and then spend out again for an upgrade in six months time. Especially if I do a Mk1.5 swap which is looking pretty tempting! :D

I don't want to go HUGE on the brakes though as I would like to keep it on small wheels for the stealth look, I think they look great on the stock 14's and it'd probably less unprung weight that the cheap set of 15's that are on it at the moment.
silentk
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Re: Celica ST165 calipers under 15" wheels?

Post by silentk »

Adam W wrote:Yeah, the standard brakes are FUBAR, but after working out the costs for a proper refurb kit, new standard sized pads, discs, etc, it only works out around 25% more expensive to go for bigger calipers all round. I drive pretty hard, so I would rather spend the money now, than refurb the standard brakes, and then spend out again for an upgrade in six months time. Especially if I do a Mk1.5 swap which is looking pretty tempting! :D


That's the conclusion I came to, I needed to refurb my callipers and needed new discs as well after getting terrible fade on track and on the road. So I got a pair of single pot ST185 callipers from the GT4OC for the price of the refurb kit (I think there is a pair up for sale on there at the mo for 50 quid), and a pair of brand new discs already drilled for the MR2 for only 20 quid more than a set of MR2 discs. I also worked out the running costs would be cheaper as I wouldn't need to go for super duper pads at £100 a shot for track work, and would probably be able to get away with the standard pads.
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