When I first got my car I tore the engine to find domed pistons and 2
cylinder head gaskets. I dont know if the 2 gaskets were because how much
the cylinder head was cut or for piston/valve clearance. I put stock pistons
back in but I wish I install new domed ones.
Ken
DATSTER
----- Original Message -----
From: <Fred_Katz@ci.sf.ca.us>
To: "Ronnie Day" <ronday@home.com>
Cc: "Roadster List" <datsun-roadsters@autox.team.net>
Sent: Monday, May 22, 2000 6:01 PM
Subject: Re[4]: Back on the road again!! [distributor timing]
> Ron,
>
> Excellent point. Hmmn, Stephan, did you shorten the stroke or modify the
> chamber on the head? (And you guys are sure brave to play around with this
> stuff!)
>
> Fred
>
> _________________________ Reply Separator _________________________
> Subject: Re: Re[2]: Back on the road again!! [distributor timing]
> Author: Ronnie Day <ronday@home.com>
> Date: 5/22/2000 7:00 PM
>
>
> >When Stephan told me he installed domed pistons I asked the same question
> >with raised eyebrows. When we started her up, it didn't blow apart and we
> >didn't hear any noise so it must be clearing the valves! His cylinders
are
> >20-over bored so the compression isn't as high as it could be.
>
> If the engine has been bored, without a corresponding increase in chamber
> volume, then that increases the CR since you're increasing the swept area
> in the cylinder. In other words you're stuffing more cylinder volume into
> the same chamber, so the CR is higher.
>
> That's why we tend to be careful when putting L-series heads on Z-22/24
> blocks. Chamber shape, cam overlap and other factors can have a big
> effect on the effective, as opposed to static, CR, and also on the
> tendency of a motor to ping and detonate.
>
> FWIW,
> Ron
>
>
> Ronnie Day
> ------------------
> Dallas/Ft. Worth
> ------------------
> '71 510 2-dr (Prepared Class Autocrosser)
> '73 510 2-dr (Street Toy)
>
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