When do u shift?

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Swap fan

Active Member
ok. i have a 91 crx hf chassis, hf tranny, and 91 si motor.
my questions are:
when would u suggest to shift, to save gas?
When do u shift? (ur motor, tranny)
 
The faster your motor is spinning the more gas it's going to use. For normal everyday driving in a Honda 3,000 - 4,000 RPMs sounds about right...
 
gas saving,shift around 3...
racing i like to bounce it off the rev limiter a couple times before shifting:D
 
racing i like to bounce it off the rev limiter a couple times before shifting:D

just so you know, that slows you down..

anyways.. wanna save gas? dont drive, haha..

just stay off the pedal and shift around 3-3.5k rpm
 
When I had my Accord; 3200-3500rpm, with my Civic; 4000rpm, my brother's Civic(CX); 4300-4500rpm.

I just pretty much keep the accelerator steady and shift when it feels like power is falling off. Hell, my Civic does ~70mph at 4000rpm anyways(yes, in 5th gear) :D
 
k if i were to constantly be at
35mph
or
50mph
what rpm would u guys recommend to be at?
 
As low as possible. Doing 60km/h (35mph approx) im doing 2000 in fifth, i do have a J1 tranny so its tough to keep the rpms low but its decent. Depending on the movement of traffic i normally shift at 2,500 to 3000.

Alot of it depends on torque, more torque, less rpm needed to move, but usually the engine is larger so gas usage it more. Its a bunch of factors.
 
Doesn't it use more gas though if you lug it?
 
From my experience, pushing the accelerator down to keep speed uses more gas than just letting it rev with barely pressing the accelerator at all.
 
The faster your motor is spinning the more gas it's going to use. For normal everyday driving in a Honda 3,000 - 4,000 RPMs sounds about right...

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 ^_^
 
From my experience, pushing the accelerator down to keep speed uses more gas than just letting it rev with barely pressing the accelerator at all.

deffinatly

Doesn't it use more gas though if you lug it?

deffinatly. no torque down low. dont shift under 3k if you plan on reaching 30mph or above.
 
i shift one of my cars at 3k every gear and im in 6th gear by the time i get a 8th mile away lol,
 
Bouncing off the rev limiter? Holy sheep shit. When you hit the rev limiter, do you know what is actually happening Injen? Fuel cut/Spark cut. Fuel + Spark Cut = Bad news. Thats why we have two step :) Holds the RPM wherever you desire, and keeps fuel + spark to the engine. Wonderful for those 6500 rpm launches. :D
 
mine i usually rev to about 2.8 and then 3.5 at 3rd and skip 4th
 
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.

You're right, yeah. My answer was somewhat over-simplified. Obviously the amount of throttle you're putting into it will have an effect on the amount of fuel you're burning. I was just saying as a general rule (and assuming that you're not constantly flooring it) the lower you shift the more gas you'll conserve...
 
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