Keith Ehrlich wrote:
> 1. There seems to be variying opinions over what the highest compression
> using garden variety premium gas the head can handle with reasonable
> timng advance. For example, BPNW recommends 8.8:1, Goodparts uses 9.7,
> Brit Frame and Eng said go for 10 but can be talked back down to
> 9.5-9.75 Ted Schumaker says go for 10. Given my new cam specs cam and
> its overlap, what do listers think is the ideal compression to maximize
> power and be assured of decent timing advance with pump quality premium?
I posed the same question to my Machinist who is building my engine and his
response went something like this: "Well you used to be
able to run high test pump gas in 10.5:1 engines, but that is when the pumps
contained real gas! Now, he says that much over 9.5 will
cause pinging unless octane boosters are added to the fuel. His recommendation
is to use real live "Racing Fuel" for those high
compression engines.
>
> 2. British Parts Northwest seems to be the only shop with off-the-shelf
> comped and reconditioned heads and their price is not a lot different
> from that quoted at my local shops for similar work on my original head.
> Anyone have experience or opinions on their product and/or alternative
> off-the-shelf solutions? ( this one can be responded to offline to
> protect the guilty).
The head work really needs to be matched with the other mating pieces to get
the most out of the work. To buy an "off the shelf"
reworked head carries with it a lot of assumptions that may or may not be
accurate. For my money, I am having my machinist do the
head to match what he is doing with the engine and the intake manifold to get
the best flow possible.
Regards,
Joe Curry
>
> Thanks gang.
>
> It would be impossible to own this car without the help of this list.
>
> Keith Ehrlich
> 74 TR6
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