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I think I killed it :-(
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MikeDanger  



Joined: 21 Nov 2002
Posts: 579
Location: Denver

PostPosted: Mon Jan 04, 2021 1:22 pm    Post subject: Reply with quote

US s2 is 8.0 C:R
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Fasteddie313  



Joined: 29 Sep 2013
Posts: 2180
Location: MI

PostPosted: Tue Jan 05, 2021 2:41 am    Post subject: Reply with quote

Carrera RSR wrote:
ARP fixings requires ARP grease

It comes with the studs though..

MLS is probably the better way to go, but I haven’t had any problems with my new stock gasket under ARPs.. Yet..

It’s debatable what one needs to do to the finish on the block deck and head surface in order to use an MLS as they require a certain standard of smoothness/finish..

MLS gaskets can also be bought in many different thicknesses, so you can either retain your stock CR, or raise or lower your CR, depending on what thickness gasket you choose..
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Carrera RSR  



Joined: 08 Jan 2010
Posts: 2163
Location: Somerset, UK

PostPosted: Tue Jan 05, 2021 10:25 am    Post subject: Reply with quote

50RA finish on the surfaces for Cometic. Pretty stock finish, nothing special.

Stock HG don’t last too long on 1.0bar + boost.
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1980 931 - forged pistons, Piper cam, K27/26 3257 6.10 hybrid turbo, 951 FMIC, custom intake, Mittelmotor dizzy & cam pulley, H&S exhaust, GAZ Gold, Fuch'ed, Quaife
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Then www.924board.org/viewtopic.php?t=31252
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bureau13  



Joined: 07 Sep 2017
Posts: 352
Location: South Florida

PostPosted: Mon Feb 22, 2021 3:19 pm    Post subject: Reply with quote

So I'm finally taking the head to the machine shop. I keep looking for valves or a head, but haven't been able to find much yet, but I realized if someone were to come tell me they had some valves, I don't really know exactly what I need. So I'm going to have them tear it down and tell me exactly what I need. Probably should have done that from the start.

In the meantime, I have the tops of these pistons. A few people have mentioned sanding down the edges where they impacted the valves, so I was wondering how smooth they need to be, and what you guys recommend for this. Would you use some sort of sanding wheel on a dremel, or should this be done by hand, etc?
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1982 931
1986.5 Silver 928S
2007 Hummer H3 (Daily Driver)

Past lives (I miss them all):
2004 RX-8 (Wrecked)
1993 RX-7 (Sold)
1987 RX-7 Turbo II (Sold)
1985 RX-7 GSL (Stolen)
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peterld  



Joined: 10 Dec 2006
Posts: 827
Location: Noosa Heads QLD Australia

PostPosted: Mon Feb 22, 2021 11:12 pm    Post subject: Reply with quote

Either/or........you only need to remove the sharp edges to avoid detonation. It doesn't need to be a work of art......remembering that the more you remove the lower your compression ratio.
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Last edited by peterld on Wed Feb 24, 2021 12:30 am; edited 1 time in total
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Mike9311  



Joined: 14 Dec 2004
Posts: 1057
Location: Chicago-ish

PostPosted: Tue Feb 23, 2021 12:45 am    Post subject: Reply with quote

Just brake corners and smooth things out. Depending on how bad things are are start with 400 grit sandpaper and move to 600+. You can also use one of those dremel scotch brite wheels but be careful. Hard to control sometimes. Be light handed and have patience


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1980 931 since 1989
1981 Ideola 931 Club Sport
1982 931 Entwicklungsfahrzeug
1979 924 NA M650 Herausnehmbares Dach
1982 931 Red Resurrection - 951 IC
1982 931 parts car / resurrection?
1980 924 NA (R&D lightweight)
1982 931 wana-be GTR race car
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bureau13  



Joined: 07 Sep 2017
Posts: 352
Location: South Florida

PostPosted: Tue Feb 23, 2021 4:04 pm    Post subject: Reply with quote

OK, sounds good, thank you everyone.
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-----------------------------------------
1982 931
1986.5 Silver 928S
2007 Hummer H3 (Daily Driver)

Past lives (I miss them all):
2004 RX-8 (Wrecked)
1993 RX-7 (Sold)
1987 RX-7 Turbo II (Sold)
1985 RX-7 GSL (Stolen)
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