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Old 10-05-2010, 08:31 AM   #9 (permalink)
Gasoline Fumes
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Join Date: Oct 2009
Location: New York State
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CRXFi - '88 Honda CRX XFi

Insight 256 - '00 Honda Insight
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Gen-1 Insights

Insight 5342 (no IMA) - '00 Honda Insight
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Quote:
Originally Posted by mwebb View Post
if you use the 3tech economy cam do not use their +10 cam wheel .
because if you do it advances EVC Exhaust Valve Close to 334 degrees ATDC which does not allow all of the spent gases to escape into the exhaust before the exhaust valve closes
so
it is kinda like having built in EGR that never switches off
at idle or at WOT , which effectively decreases the engine size and reduces available power
in the geo metro forum
i have put up pressure transducer waveforms showing this with the OEM cam and the 3tech economy cam with the +10 cam wheel
currently
i am using the 3tech economy cam with the OEM cam wheel , have not yet captured the pressure transducer waveforms to see EVC (it should be 344 degrees ATDC now ) but there is a noticeable increase in power .
How much advance is too much? The XFi camshaft is ground 6 degrees advanced compared to the base model camshaft. The 3tech economy cam has no additional advance ground into it.
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2000 Honda Insight
2000 Honda Insight
2000 Honda Insight
2006 Honda Insight (parts car)
1988 Honda CRXFi
1994 Geo Metro

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