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Forged pistons - what bore size? #1488555
17/05/2014 09:43
17/05/2014 09:43
Joined: Dec 2011
Posts: 17
Poland
P
PabLO20VT Offline OP
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PabLO20VT  Offline OP
Newbie
P

Joined: Dec 2011
Posts: 17
Poland
I prepare to buy forged pistons Wossner but there are 3 sizes Bore: 82mm (OE), 82.5 mm and 83mm.

Which one to choose?

I thought to make a larger bore than stock, to have new coats and fit.
I think the 82.5 mm.

If I apply 83mm bore engine will not be too much weakened? Will there be a problem at higher boost pressure? What other companies producing forged pistons do you recommend?

Where can I buy (online shop - with shipping to Poland)?

Last edited by PabLO20VT; 17/05/2014 10:58.

2.5 20VT + DSG DQ250 -> 804HP
Re: Forged pistons - what bore size? [Re: PabLO20VT] #1488620
17/05/2014 18:04
17/05/2014 18:04
Joined: Feb 2008
Posts: 1,728
London
kj16v Offline
My life on the forum
kj16v  Offline
My life on the forum

Joined: Feb 2008
Posts: 1,728
London
Neither size will weaken the bores. 82.5mm should be fine though.

I'm sure I've seen a Polish supplier of Wossner pistons somewhere on the net. Though, I can also apply to Poland. I'll PM you my website details.

EDIT: Oops, you're over your private topic limit!

Last edited by kj16v; 18/05/2014 00:44.
Re: Forged pistons - what bore size? [Re: PabLO20VT] #1488630
17/05/2014 18:31
17/05/2014 18:31
Joined: Dec 2011
Posts: 17
Poland
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PabLO20VT Offline OP
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PabLO20VT  Offline OP
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P

Joined: Dec 2011
Posts: 17
Poland
Yes, wossner piston can buy in Poland wink


2.5 20VT + DSG DQ250 -> 804HP
Re: Forged pistons - what bore size? [Re: PabLO20VT] #1488638
17/05/2014 18:54
17/05/2014 18:54

J
Jopa_zgd
Unregistered
Jopa_zgd
Unregistered
J



I'll go for 83mm, 20vt blocks are very strong and don't know that anyone had problems smile

Re: Forged pistons - what bore size? [Re: PabLO20VT] #1488639
17/05/2014 19:00
17/05/2014 19:00
Joined: Dec 2005
Posts: 17,386
Staffordshire
Nigel Offline
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Nigel  Offline
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Staffordshire
I have been running 83mm Accralite pistons for two or three years now - no problems

Re: Forged pistons - what bore size? [Re: PabLO20VT] #1488659
17/05/2014 20:10
17/05/2014 20:10
Joined: Apr 2006
Posts: 310
n.ireland
zigman36 Offline
Making a profit
zigman36  Offline
Making a profit

Joined: Apr 2006
Posts: 310
n.ireland
is your engine dismantled already? best double check that your block has not been bored out

maybe better go for middle size encase it needs rebored after a melt?

Last edited by zigman36; 17/05/2014 20:11.

Re: Forged pistons - what bore size? [Re: PabLO20VT] #1488678
17/05/2014 22:14
17/05/2014 22:14
Joined: Dec 2011
Posts: 17
Poland
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PabLO20VT Offline OP
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PabLO20VT  Offline OP
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Joined: Dec 2011
Posts: 17
Poland
The engine is not yet dismantled.
The entire engine will be built on the new parts. New crankshaft OE, new oil pump, new pulleys, new forged pistons and connecting rods.

The engine will be bore with simulation plate. The crankshaft pulleys and flywheel and simulators weight rods and pistons will be balanced. ETC.

Everything I have ordered only Wach on the choice of the size of the pistons is 82.5 or 83mm

@ Nigel - at what boost pressure you drive? From what I know you have a GT2871r A / R 0.64 and trim 48 - I have the same turbo.

Last edited by PabLO20VT; 18/05/2014 08:21.

2.5 20VT + DSG DQ250 -> 804HP
Re: Forged pistons - what bore size? [Re: PabLO20VT] #1488734
18/05/2014 11:33
18/05/2014 11:33
Joined: Dec 2005
Posts: 17,386
Staffordshire
Nigel Offline
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Nigel  Offline
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Joined: Dec 2005
Posts: 17,386
Staffordshire
Originally Posted by PabLO20VT
@ Nigel - at what boost pressure you drive? From what I know you have a GT2871r A / R 0.64 and trim 48 - I have the same turbo.


the 2871 finally died a couple of years ago, so I upgraded to a GT3071R with a billet compressor wheel

I run 1.4 bar as my day-to-day max boost - I save the 1.7 bar for "special occasions" as its just too violent for comfortable driving


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