Jerry---I was surprised to read that your understanding was that Moss
used a non-stock compression (9.5:1) ratio on their SC'd engine. I had
not seen anything advertised to suggest that they used anything but the
low Compression Ratio head, since that is "safer". We know that engines
with computer controls, plus a way to reduce charge temperatures can get
away with higher CR's, to some extent.
Anyway, I gave Moss a call. "Phillip" said that Moss "did not use
anything but a stock head (7.75:1 in this case) to do their R&D for the
supercharged engine". (They did do some head porting a little and added
a mild cam for their upgraded -160 hp- package)
Kastner said he rarely used anything but an engine dyno for testing his
race engines. Anything that measures "rear wheel HP had too many
variables to consider to make it accurate" he claimed.
Regardless, Moss' numbers at the rear wheels of these SC'd engines can
bring big grins!
If you are considering bolting on an SC, I would not raise the
compression ratio beforehand.
Dick
From: slowtoaccept@yahoo.com(Jerry Shaw)
Jerry wrote, in part...
Again, the performance gains claimed by Moss are on a non-stock engine
with a compression ratio I thought was too high for turbocharging.
Given this you can understand my reluctance to abandon the KISS
principle.
I guess I'm risk adverse (on your point of no unique path to engine
performance).
Jerry
----- Original Message -----
From: Mitch
To: Jerry Shaw
Cc: 6pack@autox.team.net ; Sally or Dick Taylor
Sent: Sunday, August 19, 2007 6:22 PM
Subject: Re: [6pack] Moss supercharging question
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