I could be wrong but I think here's where the 54cc
chamber comes from:
chamber volume
Part Number Engine year min max
C30Z-6049-AF 260cuin All 52 55
C3AZ-6049-AF 289 63/65 52 55
C50Z-6049-B 289 HP 63/67 52 55
C60Z-6049-AE 289 66 52 55
C70Z-6049-E 289 67 52 55
C7ZZ-6049-B 289 HP 67 52 55
Then they intro'd the 61.7 (min) to 64.7 (max) heads
for the 68 289 and the 69 302. Some 69/70 302's used
56.7 to 59.7 heads.
Then three 68's with 52 to 55 cc heads again
(C80Z-6049-G and -C and C8ZZ-6049-A.
Then, starting with the 302 Boss with 57.2 to 60 cc
chambers and the 69 and 70 351 heads I don't think you
see the 52 to 55 cc versions any more.
Regards,
Jim Parent
B9470139
About: Another issue, that is NOT addressed, is
where did this 54 cc chamber
come from?
The only thing Ford produced that was even close was
the 221 CID heads
at 54.5 cc,
and the HiPO 49.2 cc and 54.5 cc heads. There was a
limited run of
302-4V heads
with 53.5 cc in '68 and the smallest since was 58.2 cc
--- Steve Laifman <Laifman@Flash.Net> wrote:
> Well,
>
>
> With all do respect to the great reference material
> given by Bob (right into my
> Bookmarks), there are easier to read explanations,
> but no less correct. And the
> correct solution to the given problem.
>
> I did say my answer was quickie estimate and not
> exact, as I had left out (in
> total displacement change) the 10 cc's in the
> chamber itself.
>
> Tom Hall had it right on the button.
>
> Remember, we were NOT given any engine data. It was
> 'backed out' from the
> original compression ratio and chamber volume.
>
> The correct formula, for that specific instance, is:
> (from Tom Hall)
>
> 54 x 11 = 594 594 + (64 - 54) = 604
> 604 / 64 = 9.4375
>
>
> I had left out the (64-54) piece, and he is correct.
>
>
> the simple description form Tom Monroe is:
>
> Compression Ratio = (Swept Volume/ Clearance Volume)
> + 1
>
> The "Clearance Volume is not just the Combustion
> chamber volume, but also includes
> head gasket spacing of the head above the block, the
> "deck-height" volume, AND any
> piston shape volumes, either concave, or convex.
>
> This is all taken into account in the quoted
> example, but this just lumps all
> those factors into the existing compression
> ratio/chamber volume given, and
> assumes the only change would be the new head
> chamber volume is correctly known.
>
> Another issue, that is NOT addressed, is where did
> this 54 cc chamber come from?
> The only thing Ford produced that was even close was
> the 221 CID heads at 54.5 cc,
> and the HiPO 49.2 cc and 54.5 cc heads. There was a
> limited run of 302-4V heads
> with 53.5 cc in '68 and the smallest since was 58.2
> cc.
>
> Tom Hall correctly points out that milling a head
> gives insignificant changes to
> the combustion chamber volume, in any rational metal
> removal, so it could not be a
> 351 head, with 60.4 cc (early ) to 69 cc heads
> Maybe a Dart head????
>
> Let me throw another question on the table. (Or in
> the Punch Bowl)
>
> The 260 is listed as having 54.5 cc chambers and
> 1.67" Intake and 1.45" exhaust
> valves, same as the early 289's. The HiPo's of the
> same years ('63) were the
> same and in '64 went to 1.78 with an increase in
> chamber volume (49.2 to 54.5)
>
> So, if this is correct, it would seem that the 260
> can take the valve increases
> popular in the 289's, using Chevy sized stainless
> valves and get 1.94" intakes and
> 1.55 exhaust (with seats) and 1.60" without seats,
> in stock heads. This would
> avoid using the latter 302 non-HiPo heads with
> compression ratio killing
> chambers, or speed shop (64 cc Ford GT-40, 62.5 cc
> Holley H.O. aluminum, 60 cc
> Edelbrock) heads. Worried about hitting 3.8 bore,
> piston tops with .5 inch lift
> cams, Etc. Any hands-on experience available? I've
> got a set of good early 289's
> heads available.
>
> Steve
>
>
>
>
> --
> Steve Laifman < Find out what is most >
> B9472289 < important in your life >
> < and don't let it get away!>
>
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