2.3 NF block with MC-1 head?

[Mihnea Cotet]

Neither engine has really flat pistons AFAIK...

Mihnea

At 12:10 20/02/2003 -0500, Brady Moffatt wrote:
>Hi Alan/All,
>
>You have omitted one important item. How much of the effective combustion
>chamber is in the head vs. the piston dish? If both the KV and NG have
>flat-top pistons, this is a moot point. But if even one doesn't, then your
>calculations could be way off.
>
>Also, static compression ratio is calculated as (total volume at BDC)/(total
>volume at TDC), which means:
>KV: to find combustion chamber volume (let's call it x) (in head, piston
>dish, gasket thickness volume, etc.) 10/1= (445.2 + x)/x, so 9x=445.2, so
>x=49.47cc, NOT 44.52cc.
>
>For NG, 9x=461.8, so x=51.31cc, NOT 46.18cc
>
>Cheers,
>Brady Moffatt
>Montreal, Quebec, Canada
>86 4kq with 306,000km
>86 4kq parts car
>72 Datsun 240Z with 180,000 miles
>92 VW Golf with 194,000km FOR SALE
>in early stages of quattrosis accumulatus
>
>----- Original Message -----
>From: "Alan Pritchard" <apritchard at seaeye.com>
> > --
> > [ Picked text/plain from multipart/alternative ]
> > Just want to confirm my thoughts on this for my turbo project. My engine
> > consists of a kv bottom end (2226) and an ng head (2309), both engines are
> > spec'd at 10:1 compression ratio.
> > KV engine: 81 Bore, 86.4 Stroke
> > NG Engine : 82.5 Bore, 86.4 Stroke
> > So capacity of each cylinder =
> > KV 2226/5 = 445.2
> > NG  2309/5 = 461.8
> > Therefore for both engines to have 10:1 compression ratio, at tdc the
>volume
> > above the piston must be:
> > KV 445.2/10 = 44.52
> > NG 461.8/10 = 46.18
> > So logic dictates that if the ng head is fitted to the kv bottom, the
> > compression will be lowered: so working on the fact that my 2226 engine
>now
> > has 46.18 cc above the piston at tdc gives me....
> > 2226/5 (capacity of cylinder) = 445.2/46.18 (new volume above piston) =
> > 9.64:1
> > Does this follow, or have I missed something, my goal has always been
>8psi.
> > my head says yes, but when I posted before no one could back me up.
> >
> >
> > Best Regards,
> > Alan Pritchard
> > Network Administrator
> >
> > Seaeye Marine Ltd.
> >
> > Tel.  01329 289000
> > Fax. 01329 289001
> > www.seaeye.com
>
>
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