David Kernberger wrote:
>
> 4/22/99
>
> Glenn,
>
> Thanks for your candid reply. That's exactly what I asked for so I
> had it coming. The Buick 300 rods are not a good choice apparently. So
> maybe back to the drawing board????.
>
> The other statement you make regarding low compression ratio you do
> not substantiate with numbers. What do you calculate the ratio to be?????
> My estimate was done using Baker's 289 recipe as a starting point. Do you
> lack faith in his numbers? I have Peter Kent's compression ratio spread
> sheet but have not yet had the chance to push these numbers through it. By
> my figures, this combination gives .003" greater piston height at TDC, than
> Baker's 289 recipe, but the smaller displacement reduces the C.R. from his
> 10.38 to about 8.89. The .600" shorter stroke (compared to Baker's 289) is
> almost exactly compensated for by the .303" longer rod. So----where did I
> mess up??? I really want to know!!! Precise factual information has been
> very difficult to come by in my experience so far.
>
> It happens there are a number of reasons I am choosing this block,
> crank, head, cam, and carburetion combination which are not really open to
> change, so I need to limit the discussion to these parameters. The only
> unsolved part of the equation is the correct piston and rod combination. A
> maximum CR of about 9.00:1 is what I seek. I have 2 sets of Rover Rods,
> many Olds F-85 rods, and 1 set of small block Chevy rods, but I have not
> found any pistons with the correct compression height and bore size to
> match these other components. Can you supply the correct combination? For
> Rover rods, I think the compression height would need to be about
> 1.880",flat top, or equivalent in dome or dish.
>
> Apparently even Chrysler rods of some sort have been used in these
> engines, though I do not yet know which ones. Also I have often wondered
> whether anyone has used any other Buick rods, or any G.M. v6 rods, some of
> which use the same big end bearings as the Rover/Special/F-85 ones. My
> main reason for reboring is that I need new pistons anyhow so I might as
> well pick up the 2 cubic inches that result from the recommended maximum of
> .020" overbore.
>
> So------if you feel like making any more candid replies, they will
> certainly be welcome.
>
> Any feedback from others is also welcome.
>
> Cheers,
>
> David Kernberger
David, I have talked with MR. BAKER a good bit & he knows his
stuff!!!!! Bakers 4900 & mine has a 3.4 in. stroke the 3900 has a 2.8
in stroke. If you put a longer rod in to push a shorter piston
compression height piston up the cyl. were it needs to be for the right
compression it is still a 3900, with a longer rod ratio. this motor just
starts to run with a 9-1 comp. raito. 9.5 -1 ratio is what I run & I can
use 89 oct. with no problem!!!! I HATE the high test rip-off price!!! If
you need a 300 crank I have 2 ground ready to ballance & inst & 2 that
need to be ground If you would like to talk more about your motor I will
have to ask you to call me (I CAN'T TYPE) & it's taken me days to wright
this!!!! (dumb old mech.) M-T 9-2 I will be in & out sat. 9-3
302-734-1243 Thanks Glenn
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