11/3/99
Glenn,
There may be other options worth considering. There is nothing
wrong with the Olds F-85 design. In fact, the 6th head bolt is better for
sealing. The major limitation of the F-85 is that fewer new parts are
available for the valve train, and no original equipment pistons that I
know of at all. The block, crank, and rods are nearly identical and Olds
heads are equal to the Buick heads for power output.
The Buick Special used only 1 head, but 3 different pistons, with
different dish volumes, to achieve the 3 different compression ratios
available, which were nominally 8.8; 10.25; and 11.0 to 1. The combustion
chambers are about 36 cubic centimeters in volume.
The Olds approach was the opposite-1 piston type, flat head, (some
with valve reliefs) and 3 different heads with different combustion chamber
volumes to achieve the nominal 8.75; 10.25; and 10.75 to one compression
ratios offered. The volumes were about 51 cc; 43cc; and 38 cc respectively.
Option 1: You are probably using new Buick pistons, which are only
easily available in the 8.8:1 C.R. You also have new Buick valves. Get
some bare Buick heads, use your valves, and rebuild them as you originally
intended. I could sell you some usable heads, along with valve springs,
retainers, locks, rocker arms, rocker shafts, and rocker covers for a
fairly reasonable price. Others may be able to supply this stuff also.
You would get about 8.8:1 compression ratio and would be OK, except you
would have a couple extra F-85 heads left over.
Option 2: If you have the 4-barrel (10.75:1-38 cc combustion
chamber) Olds heads, just rebuild them, send your Buick valves back, and
you would have about 8.5:1 C.R. The 2-barrel heads would give way to low a
C.R. I don't know what is wrong with your original valves, but refacing
them is perfectly OK as long as the "margin" on the exhaust valve heads
does not get too narrow. If you would need any replacement Olds valves, I
probably have what you need and would let them go at a fairly-reasonable
price. No leftover heads this way.
To find out which Olds heads you have, first check whether the
intake manifold is 2- or 4-barrel. If 2-barrel, then Option 2 is out. If
4-barrel,
then turn the heads over and find the casting number on the bottom side
near the 2 center intake ports. If the last 3 digits are 534, you have the
correct heads. If the last 3 digits are 829, it might be OK but the C.R.
would be a bit low.
Option 3: Go for rebuilt Buick heads as mentioned below. Be sure
you know what pistons are going in and what C.R. to expect. You still have
2 leftover heads.
Other Choices? Rover pistons are available in 9.35:1 C.R.. This is
also based on a 36 cc combustion chamber. This would allow you to use
Buick, Rover, Olds 829, or Olds 534 heads, and have some latitude in C.R.
choice. I think Silvolite offers a high compression piston also, but the
word seems to be they are almost impossible to get ahold of and are only
made on occasional special production runs.
Anybody have any other ideas??? Or am I just all wet even with these?
Cheers,
Dave Kernberger
*************************************************
>The title about says it all. I'm looking for a set of rebuilt Buick heads to
>replace my Olds heads that need to be rebuilt. If they were to include the
>valve covers that would even be a bigger plus.
>
>Thanks again,
>
>Glenn
>Now realizing why everyone told me to buy an already rebuilt engine. I guess
>this is what I would call a "learning experience". About the only positive
>note from all this, is that the next V8 conversion should be a piece of cake
>:-)
|