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Old 05-17-2012, 11:54 AM   #19 (permalink)
Gasoline Fumes
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CRXFi - '88 Honda CRX XFi

Insight 256 - '00 Honda Insight
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Insight 5342 (no IMA) - '00 Honda Insight
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Originally Posted by Christ View Post
Unfortunatley, I have no use for a 350 LOL.

Anything diesel laying around? Or bikes, scooters, etc...
I have a few old mopeds....

Originally Posted by Christ View Post
I might have a junk 16V head laying around if you want to practice clearancing it for the HF cam... You can have it if you want.
Thanks, but I actually have a spare head I can play with.

Originally Posted by orangustang View Post
I wonder if you would be able to achieve better efficiency by leaving the second exhaust valve functional, like the first stage on the 3-stage VTEC engines. If I had a SOHC rocker-arm setup like yours, I would think it worthwhile to play around with disabling one intake valve, then one exhaust valve, then one of each, and see which works best. They all seem like they would have their advantages, but I'm not sure which one seems the most advantageous.

2 intake, 1 exhaust = increased EGR effect from decreased exhaust flow, but higher VE from better intake flow
1 intake, 2 exhaust = lets less air into the engine for reduced consumption, but removes some exhaust restriction for better performance
1 intake, 1 exhaust = less total flow, still balanced like the 4-valve. Definitely way less power with the 4-valve lift, as you've seen.

I'm not sure which of these would result in the best fuel economy. As I said, there's some reasoning to support each concept, and it probably depends on your driving style.
I've been wondering the same thing.

Originally Posted by hawk2100n View Post
The 8V cam probably has significantly higher lift than the 16v cam. Curious to see how this comes out, the FE system will still assume 16 V and the associated airflow and fuel accordingly. Maybe the decrease in power will improve driving habits more than anything, although I would accuse my 106 hp 16v Civic of being too powerful.
It's running in closed loop, but I don't know if that can fully compensate for the reduced airflow.
2000 Honda Insight
2000 Honda Insight
2000 Honda Insight
2006 Honda Insight (parts car)
1988 Honda CRXFi
1994 Geo Metro

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