My Junx

The other day I was driving and sorta spaced out a little in traffic and realized I was in 5th gear just rolling down the road at like 30 MPH and the RPM was pretty dang low. Anyway, I down shifted and got it back to normal but that got me thinking.... I know in my old VW if you dip a little to slow for the gear your in it knocks a little and burns a little oil. Or if you accidently try to start from 3rd gear it burns oil pretty bad (not that I do that often but it prolly happened twice..shot shifter bushings)
SO, would this sorta oil burning happen in our engines if you were in the wrong gear for the speed? Or what sort of damage would this cause if someone made a regular habbit of it?

Kenteth

You wv had more torque then your rx7 probably. Anyhow depends on what rpm we're talking. Sometimes I'll cruise 40mph in 5th. Theres only enough power to keep moving, but it works for a decent cruise gear on a flat road.

driftseshrx7

from what i learned its pretty bad to drive them at lower rpms, i heard its healthier and the engines are happier to drive around 3 to 4k . not sure if thats right or not but just heard that from word of mouth lol

Kenteth

I suppose I could forsee carbon buildup with extended low rpm cruising...

slpin

iTrader: (9)

you know them automatic rx7s?

their rpm gets REALLY low when you cruise at 30mph-40mph

same wtih 5th gear

give it gas, stays in gear, till your really on it

i think it is fine as long as your not flooring it and the car bucks, etc

My Junx

yeah, I was just wondering how the engine wear/potential damage from extended very low rpm use would compare to a piston engine.

slpin

iTrader: (9)

i would think as long as your not laboring the engine, like flooring in 5th at 1300rpm, it should be fine.... wear shoudl be less cause of lower rpm?

Kenteth

Better gas mileage?

Rx7TyreBurna

iTrader: (1)

Better gas mileage.... 16 instead of 15 MPG... heheh

RexRyder

iTrader: (10)

the rotary is not some magical engine from outer space, its just like any other engine. i cruise at 30 in 5th, been doing it for years. of course on down hill or level surface. also EVERY car is different so it depends.

Tofuball

My S4 GXL: I have found better fuel economy always shifting a little above 2K except for 4th to 5th, where I shift at 2.4K-2.6K or higher.

YES IT IS.

slpin

iTrader: (9)

heh, i use my afc and lean out 5-10% under 3000rpm
seems to run better too, a lil more power
and then i give less than 25-30% throttle
and shift around 2500 on the tach, 2300rpm on the afc (yeah, tach is off)
it seems to get good gas mileage..............


but then i keep trying to shoot flames
sooo all my efforts are wasted

Bob_The_Normal

Heh, I figured out how to shoot fireballs easily...

Disconnect your water thermosensor... insta-rich.

--Gary

therotaryrocket

man, you guys shift at low freakin rpms, does the shift up light even come on when you shift? i usually shift when the shift up light comes on, I know low rpms cruising in a carburetated car usually leaves it in the idle cylce so 35mph in 5th gear would be worse gas milage than 35mph in 4th gear, not sure if this is true for fuel injection. and starting off in 3rd gear will burn your clutch up really quick.

BlaCkPlaGUE

Its not the same as injection, injection doesn't have an IDLE mode, it just adds fuel for the exact amount of air that it detects.

I think the best way is with a fuel controller, lean that bitch out like the other guy in here for the low rpms and stay in a high gear. At that rpm it isn't going to overheat or anything.

88IntegraLS

I cruise at 35 in 5th a lot, street port and all. It's not bad for the engine if it's in a good state of tune. If anything, low oil pressure would be something to look out for, but rotary bearings take less strain than piston engine bearings due to how little leverage the rotors have on the eshaft compared to connecting rods to crankshafts.