x_flow57
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| posted on 1/2/08 at 11:50 AM |
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Alloy or stainless brake pistons?
Hi Folks
Can anyone see any problems with replacing the alloy pistons with stainless in alloy 4 pot brake calipers?
Nick
<<<<For Sale
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tegwin
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| posted on 1/2/08 at 11:51 AM |
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....Doesnt stainless corrode Ali...
So if you put them both together its going to corode....
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x_flow57
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| posted on 1/2/08 at 11:57 AM |
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No not saving weight
My son has bought a mini van with 4 pots on and one has decided to deposit all its fluid onto the drive overnight caused by corroded alloy
pistons.
Nick
<<<<For Sale
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stuart_g
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| posted on 1/2/08 at 12:05 PM |
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I think wilwood have some of their pistons in stainless and they are alloy body, so I don't see why not.
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Mr Whippy
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| posted on 1/2/08 at 12:09 PM |
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quote:
Originally posted by x_flow57
No not saving weight
My son has bought a mini van with 4 pots on and one has decided to deposit all its fluid onto the drive overnight caused by corroded alloy
pistons.
Nick
<<<<For Sale
erm sorry I deleted my post when I realised you where actually fitting stainless...
low on food, off now to recharge with greasy burger.
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02GF74
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| posted on 1/2/08 at 12:12 PM |
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they shouldn't be in contact so shouldn't corrode; unless the brake fluid casues some chemical reaction between the two.
but then the LR master cylinder is alloy as well as clcuth master /slave and I have never heard problkemns weith the alloy; stainless brake pistons
are avaialble so either someone has not tdone the electro-chamistry homework or else it is ok.
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tegwin
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| posted on 1/2/08 at 02:49 PM |
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It depends....
i was under the impression that alloy callipers with a stainless piston had a coating on the bore of the barrell to stop corosion...
So if you dont have that coating, it might corrode..
Then again I might be talking out of my arse!
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britishtrident
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| posted on 1/2/08 at 05:03 PM |
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For road use alloy calipers are bad news.
Stainless steel pistons should be OK
[I] “ What use our work, Bennet, if we cannot care for those we love? .”
― From BBC TV/Amazon's Ripper Street.
[/I]
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x_flow57
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| posted on 1/2/08 at 07:46 PM |
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BT, apart from the obvious (corrosion) are there any other drawbacks with alloy on road cars?
Nick
<<<<For Sale
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Syd Bridge
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| posted on 2/2/08 at 06:53 PM |
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quote:
Originally posted by x_flow57
BT, apart from the obvious (corrosion) are there any other drawbacks with alloy on road cars?
Nick
<<<<For Sale
I'd like to know where BT gets his info.
There's far too many production cars on the road using alloy calipers, for his statement to come anywhere close to reality.
They've been used on road cars for years, and will continue to do so.
Syd.
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NS Dev
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| posted on 2/2/08 at 10:24 PM |
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Yep, I think maybe somebody better tell Mazda, Nissan, Mitsubushi, Porsche and a few others that they better stop using alloy calipers!!
Back to the question, no there's no problem with stainless pistons in alloy calipers, as long as the car's not being stood for long
periods. There is an issue with dissimilar metal corrosion but as said above, the two shouldn't be in contact in normal use, but can be once its
been stood for a bit.
Realistically though, it will be fine, just go for it!
Retro RWD is the way forward...........automotive fabrication, car restoration, sheetmetal work, engine conversion
retro car restoration and tuning
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britishtrident
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| posted on 3/2/08 at 09:34 AM |
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Fiat used alloy calipers on some models for a long time -- in wet salt laden UK roads they used sized after 2 years use. PGA group used alloy
calipers on some models as a production alternative to steel/CI, the alloy ones were nothing but trouble.
Alloy calipers and wheel cylinders have always been a problem when exposed to salt --- back in the 50s and 60s' alloy wheel cylinders were the
norm and replacing seizied wheel cylinders kept a lot of garages going.
[I] “ What use our work, Bennet, if we cannot care for those we love? .”
― From BBC TV/Amazon's Ripper Street.
[/I]
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x_flow57
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| posted on 4/2/08 at 11:09 AM |
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Thank you all for the replys.
Stainless pistons now fitted and stopping well.
I'm sure the car is not handling as well as it was before what with all that extra unsprung weight.
Being serious for a mo, the stainless are incredibly heavy compared to the alloy.
ATB Nick
<<<<<<For Sale
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britishtrident
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| posted on 4/2/08 at 12:23 PM |
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Usually steel pistons are hollowed out not solid.
[I] “ What use our work, Bennet, if we cannot care for those we love? .”
― From BBC TV/Amazon's Ripper Street.
[/I]
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