So I know this sounds like something someone new would post but....I've got a question. when driving around town I throw it in fifth and my rpms are in the area of 2.5K-3K putting me at a speed of 50-60kph(our in town speed limit) now with that being said in theory the lower the RPM's the less gas used right ?. but you're lower in the power band and sometimes i feel as if the car has to work harder(i'm not bogging) and thus using more gas;. my other theory is I could cruze in 3rd of 4th and be at 3-4K still at 50-60 kph but be in a more usable power band and have zero ! slight bogging feel flip side is you're at a higher rpm range for longer. is this a viable theory I may change up my driving style what do you guys do lower rpms=less gas being used or higher rpms but in the better powerband ?. car has bolt ons w/gsr trans gets about 380-420 kms in town with kinda aggressive drivng.

 

I've thought about this many many of times too actually haha. At first thought, yes you would think that the higher the gear you're in the lower the rpm the higher the mpg. But like you said you have to give more throttle to get going, thus using more fuel.

I guess it all depends on the situation. being in a higher gear is great but once you're engine vacuum reaches zero then you should downshift! ( had a vacuum/boost gauge on my wrx and when it would reach zero right before boost i would shift up/down to save fuel )

 

i always gun it to 3k then shift. less time accelerating, and more efficient due to less pumping.losses from the butterfly. i only use 5th above 50mph. my da integra gets 30mpg average like that


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I've also questioned this while driving before. I know aero kicks in around 50mph, too...interesting stuff.

 

would driving in 5th cause any harm to the engine or clutch ? I don't bog it but i'll notice it almost happening on it's own here at there. another reason for the lower gear driving as the car get pretty loud after 4K. what i'll normally do is shift at 4-5K from first to 2nd then put it in 5th from there. clutch is slipping when I go WOT(8K shift) so this 5th driving may have to stop till I get that fixed lol.

 

car fets louder after 4k because thats were the cams start picking up power. you do 1-2-5? thats a bit harsh for the transmission. why not just go through the gears instead? i dont use 5th unless the rpm will be above 2500rpm or so. having the engine luggin around below 2k just sounds bad and im sure the pump isnt making full oil pressure so i feel like im just slowly killing it lol


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Agree on 5th @50mph. 45min for 5th imo. I prefer shifting 3-3.5k when going easy

 

Well it's more like 1>2>4>5 now that I think about it but yes I'm sure it's not the best. 2 to 3rd grinds(always has) now 4th to 5th and occasionally 3rd to 4th. probably best to keep it in 4th in town sitting at 3.5K I feel like there's a bigger drop from 4th to 5th then the other even when taking it to the "top" of each gear going WOT. it's not an ls 5th afaik og gsr tranny (it's not an LSD).

 

3rd grinds because of the steep drop between 2 and 3. by shifting 2 to 4 youre killing you transmission even worse since its an even steeper drop from 2 to 4.


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where do you guys like to keep the RPM's when cursing ? i'm liking just over 3K for "feel" but my stupid exhaust makes it a little hard(buddy club:spec 2 lol).

 

About 2.5-2.75 is where I'm sippin gas

 

off a green light ill shift at around 4000 - 4,500 if its a higher speed limit road and under about 50ish% throttle. then pretty much as soon as i shift into 4th im already at 3,000 - 4,000 rpm so i go right into 5th. i have a type R motor and trans.
I cruise all day in 5th unless i got to get up and go then ill always downshift, i never put a strain on 5th. ill probably be around what S2Bump said 2.5 to 2.75 rpm around town

 

its conversations like this that make me miss my wrx... any speed above 50mph in 5th i would never downshift, even getting on the highway. freaking boost and torque man.. something us N/A hondas know nothing about

 

Best for fuel economy in theory is:

Low engine speed
Large throttle opening
Lean mixture

So the best strategy is to use a lot of throttle but shift very early. However cars sometimes gain efficiency as they gain engine speed because the throttle is not the only factor in pumping losses. B-series cars are tuned for high rpm operation and they seem to benefit from some revs. I get better fuel economy with my itr transmission than i did with my ls or gsr transmissions.

 

hmmm makes sense only thing I'm unsure of is some times you have to give it more throttle than you would if you were at 3.3K in 3rd vs at 2.1K in 4th/5th lol I know that the gain is SO small but im still intrested in knowing. ya i'd figure longer gears>shot gears of the YS1 and Y80 (gsr).

 

thats the theory I follow. ironically when my old trans was in with no working 5th, I was averaging about 28-30mpg with a cruising speed of something like 75mph. I know most of the time my rpm was hanging around 4000-5000rpm. stock ls engines seem to be happiest around 3500-4500rpm economy wise


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well im not too sure where to drive at lol. gotta get rid of this stupid 255 lph fuel pump before I can see any results so to say with "city" driving I can get about 400-420'kms to a tank with cruzing in 5th sitting at 2K rpm's