As a new member, I've been spending a lot of time going through the
archives, but it's a slow process. A few questions:
Has anyone run an engine simulator on TR3/4 engines? It seems like a
good way to dial in cams, compression, etc. It is a fast and cheap way
to experiment, and an excellent tool when used in conjunction with a
dynamometer. I played around some with Engine Analyzer. I could get
close, but really need some flow bench data to do the job right. Has
anyone published flow data for these engines? I'd like to use the
simulator to look a cams. I have a gut feeling that about 90% of
modified engines are overcammed (too much duration). My TR3A (ex Jeff
Wilt/Bob Kramer) has about 10.5:1 compression and a 304 degree duration
cam. I saw Greg Solow's post which recommends cams based on compression
ratio. Usually the cam duration is tied to the RPM range where you want
power. From what I read, these crankshafts tend to let go with
sustained operation around 6500 RPM. So why would you ever want to run
a 300 degree cam which produces power at 4000 to 8000 RPM, when you
could run a 290 degree cam which produces power at 3000 to 7000 or even
a 280 degree cam that produces power at 2500 to 6500?
Larry Young
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