Celica GT4 WRC 4 pot caliper conversion
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Categories: MR2 Mk2 Articles -> Brakes
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[url=https://imoc.co.uk/app.php/kb/viewarticle?a=98&sid=bc4f1692aae08b9aca8860af0608b517]Knowledge Base - Celica GT4 WRC 4 pot caliper conversion[/url]
First things first, the calipers are NOT a bolt on fit, the spacing of the bolts is different, also GT4 discs will not fit as they have a 100mm PCD as opposed to a 114.3mm of the MR2.
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I used discs from a Lexus LS400 which have the right bolt spacing, disc height and a diameter of 313mm, which is plenty! they were also reasonably priced from www.brakesint.com.
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The biggest issue is bolting the caliper to the hub.
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![Image](http://i32.photobucket.com/albums/d24/skinthespin/bracket1.jpg)
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The strut mounting bolts are bolted straight into this bracket
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As can be seen from the picture below the bracket is not that simple, with the strut holes not being planar with the hub face.
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![Image](http://i32.photobucket.com/albums/d24/skinthespin/bracket2.jpg)
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The lower mounting lug hole needed moving towards the centre of the axis by 6mm in order for the pad to sit correctly on the disc.
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![Image](http://i32.photobucket.com/albums/d24/skinthespin/hub1.jpg)
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Please be aware that you should not cut lugs off either calliper or hub and re-weld as you do not know the correct specification of the material and therefore it isn't possible to be 100% confident that you are using the correct weld wire, plus assuming you are pulling 1G under braking then a quarter of the weight of the car may be going through each weld.
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The caliper width forced me to space the wheels out 5mm, therefore I needed to use extende wheel studs, the old ones were pressed out and new one pressed in using a hydraulic ram.
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The caliper mounted provisinally to the hub can be seen below:
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![Image](http://i32.photobucket.com/albums/d24/skinthespin/hub2.jpg)
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Although the caliper has
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The whole lot was offered up to the car, as you can see below the caliper is a substantial size!
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![Image](http://i32.photobucket.com/albums/d24/skinthespin/gt4_3.jpg)
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The brake hose no longer reaches the caliper, at least not when you utilise the retaining bracket on the strut.
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So there you have it, easy! All in cost was around
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the pic below is the brakes on the car, I havent used it for a little while so the discs have gone rusty, although I assure you there brand new!
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![Image](http://i32.photobucket.com/albums/d24/skinthespin/brakes1.jpg)
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![Image](http://i32.photobucket.com/albums/d24/skinthespin/gt4_1.jpg)
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![Image](http://i32.photobucket.com/albums/d24/skinthespin/000_0482.jpg)
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