When do u shift?

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Racing I shift @ 9200 and cruising @ about 4k.

LS/vtec fully built s2s3 cams.
 
I'd like to critique that first statement.

I think in very general terms, you are correct, the faster the motor spins, the more gas is going to go through the cylinders.

But, since we're EFI, not just some dumb carb, part throttle is going to be greatly improved. I'm thinking that drag, gear ratio, gravity, etc will all affect this, but possibly cruzing at one steady speed at a particular rpm higher than 'normal' could use less gas. The rotational mass of the motor's parts increase with speed. Thus, load on the engine is marginally reduced. And the ECU can make adjustments to the A/F, possibly making the higher rpm more efficient.

For instance; I've noticed I use less gas going 90mph (approx 5k rpm in 5th) than going 80mph (approx 4.4k rpm in 5th). Very marginally so, but it adds up.

Or if your still unclear on my concept, think back to when you've ridden a bicycle. It takes more effort to travel the same distance pedaling slowly compared to pedaling more quickly. It is more efficient to ride fast, to a certain degree (depending on wind, powerband [human powerband], etc).

Input on my theory? I know there will be. Constructive criticism please.

[@ OP's original Q] I've got a JDM B16A SiR-II with Y21 trans (w/ lsd) and daily town driving I normally shift at about 3,500~4,000rpm. I'd say average of 3,800rpm. Accel to highway like a normal human and not racing I'd probably shift at like 4,800rpm light throttle so you don't pop vtec for no reason (throttle pressure affects vtec crossover). Deffinatly, atleast with my current stock tune, vtec owns my gas. If I WOT just 1 gear, maybe it's just me but I can see that the gas needle drops rather quick. I probably have some issue of my own.

I just wanna say, hitting the rev limiter is bad. That's only there if you miss shift. It's not a shift light. You might already know this OP, but I gotta say it, at least for Injen's sake ^_^

Um. WHAT?!

Nope.
 
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