RPM Question

gstjoker · 01-12-2006

Guys! I'm new to this so sorry for my stupidity and knowledge about this topic. If you could just direct me to a topic similar like this that has been talked about already or if not, please give me some advice.

When you're driving your manual DSM or car. Where is your RPM usually at? Mines usually between 3000 too 4000. Where should I leave it at to save more gas?

Or if I'm street racing, any advice as to how to make a fast launch? I heard someone telling me to redline 1st gear. Just wonna know more facts and advice about this if you can just give me some.

Thanks

**Kracka** · 01-12-2006

5500 rpm seems to be the norm for launching. As for driving, just keep it where you feel comfortable and the engine doesn't seem to be struggling. 3-4k rpm is fine; if you're on flat ground traveling at a constant speed you could bring it down further to 2500 rpm to get a bit better fuel economy.

Black97civic · 01-13-2006

For fuel economy, as the kracka said, as low as you can go comfortably.

niterydr · 01-13-2006

Quote:

Originally Posted by S2kracka

5500 rpm seems to be the norm for launching. As for driving, just keep it where you feel comfortable and the engine doesn't seem to be struggling. 3-4k rpm is fine; if you're on flat ground traveling at a constant speed you could bring it down further to 2500 rpm to get a bit better fuel economy.

I wouldn't recommend below 2000rpm, and usually below 2500rpm. Lower than that, and you are usually "lugging" the motor.
Not fun for bearings and such.

Jakey · 01-13-2006

Quote:

Originally Posted by niterydr

I wouldn't recommend below 2000rpm, and usually below 2500rpm. Lower than that, and you are usually "lugging" the motor.
Not fun for bearings and such.

Huh?

Shotgun! · 01-13-2006

95 RT/TT=1800rpm on highway. How's my bearings?

A//// Guy · 01-13-2006

Never heard of too low of an RPM affecting bearings... unless you mean that the oil pump isnt operating fast enough and the motor is starving? I dont think thats such a big deal with newer cars and transmission technology. Youll know when your too low in a gear because the car will vibrate and have no power.

**Goat Blower** · 01-13-2006

That also depends on how much torque an engine has. Diesels can cruise at 1300 rpm because they have an abundance of torque. The 3S's have quite a bit more torque than DSM's as well, so they can get away with a taller overdrive. Since 65mph is about 3100 rpm in a DSM in 5th gear, you'd have to be going pretty slow to get the engine under 2000 rpm in 5th. Unless you have some really tall tires, which would change the effective overall gear ratio.

LightningGSX · 01-14-2006

Lower RPM = Less stress on bearings, even at lower oil pressures

LightningGSX · 01-14-2006

BTW Engine load makes a much larger difference in fuel consumption, than RPM

tpunx99GSX · 01-14-2006

ok i cant believe the members havent ripped this guy a new one yet. i suggest that you find someone on aim or msn that knows a little bit about cars before posting this kind of total noob shit. This thread is right up there with the Exhaust flames, sounding like a neon and the other shitty threads that i have been waiting for someone to say something about.
Like i was saying before find someone with aim that knows a thing or two and ask them, then you dont waste peoples time and clog up the boards with meaningless shit like this. My other suggestion would be to read all 8000+ topics on this board or else use the beautiful search button. Nothing against you dude but the past couple topics have been simple shit that you could have found out had you done a little research.

Jakey · 01-14-2006

I'm more interested in learning about Swanny's theory of lower engine RPM equating to greater bearing wear.
Plus I'm still waiting to hear back more about Swanny's wheel spacer posts in this thread:
http://dsmstyle.com/forums/showthrea...ghlight=stress

gstjoker · 01-14-2006

Quote:

Originally Posted by tpunx99GSX

ok i cant believe the members havent ripped this guy a new one yet. i suggest that you find someone on aim or msn that knows a little bit about cars before posting this kind of total noob shit. This thread is right up there with the Exhaust flames, sounding like a neon and the other shitty threads that i have been waiting for someone to say something about.
Like i was saying before find someone with aim that knows a thing or two and ask them, then you dont waste peoples time and clog up the boards with meaningless shit like this. My other suggestion would be to read all 8000+ topics on this board or else use the beautiful search button. Nothing against you dude but the past couple topics have been simple shit that you could have found out had you done a little research.

Damn Dude! Why you pmsing? If you don't got anything good to say, don't say it?!? Got it? No one had ask you to come in here and post b/c you're sick and tired or seeing threads like this. It's everyones free will to read what post they want. If your not happy, leave!

**Kracka** · 01-14-2006

Quote:

Originally Posted by Jakey

I'm more interested in learning about Swanny's theory of lower engine RPM equating to greater bearing wear.

I understand what Swanny meant. He meant that when the engine is lugging (bucking b/c the RPM is too low and it doesn't have the power needed to accelerate) that puts additional strain on the bearings. Its an easy concept to understand, I don't see why people are jumping all over him for it.

**Shane@DBPerformance** · 01-14-2006

There is a difference between cruising at very low RPM down the freeway(not even possible in a DSM, unless you are one of those people that drive 45mph in the passing lane) and lugging a motor. It doesn't take much HP to keep a car cruising and you can get away with running it at a low RPM, if you try to accelerate more than slightly, then you might end up lugging the motor. Who knows if there would be damage from lugging it though. We aren't driving old non EFI cars that might detonate easy from low RPM lugging because of their primitive ignition timing system. If there is adequate oil pressure, there shouldn't be problems keeping the rods and crank off of the bearings, since the cylinder pressures should be quite low. If anything, it might be hardest on the pistons and cylinder walls.

tpunx99GSX · 01-14-2006

Quote:

Originally Posted by gstjoker

Damn Dude! Why you pmsing? If you don't got anything good to say, don't say it?!? Got it? No one had ask you to come in here and post b/c you're sick and tired or seeing threads like this. It's everyones free will to read what post they want. If your not happy, leave!

Im not pmsing, If you dont know shit about cars and you dont want to do a little research then dont post this stupid shit. There is plenty of info on this site and if you just keep posting stupid shit like, "hey guys, do any of you know how to plug in this lightbulb?" it shows that you didnt do shit for researching your problem. for your personal reference, before you post anything please click search, then type in a couple keywords on what you are asking, and read up about your problem, then you wont have to put in the beginning of every thread you make "sorry guys, my parents should have used a condom, but heres a really noob question for you to waste some time on..."

**1ViciousGSX** · 01-14-2006

Quote:

Originally Posted by tpunx99GSX

Im not pmsing, If you dont know shit about cars and you dont want to do a little research then dont post this stupid shit. There is plenty of info on this site and if you just keep posting stupid shit like, "hey guys, do any of you know how to plug in this lightbulb?" it shows that you didnt do shit for researching your problem. for your personal reference, before you post anything please click search, then type in a couple keywords on what you are asking, and read up about your problem, then you wont have to put in the beginning of every thread you make "sorry guys, my parents should have used a condom, but heres a really noob question for you to waste some time on..."

Damn, you really do need to find a better man.

tpunx99GSX · 01-14-2006

gstjoker · 01-14-2006

Quote:

Originally Posted by tpunx99GSX

Im not pmsing, If you dont know shit about cars and you dont want to do a little research then dont post this stupid shit. There is plenty of info on this site and if you just keep posting stupid shit like, "hey guys, do any of you know how to plug in this lightbulb?" it shows that you didnt do shit for researching your problem. for your personal reference, before you post anything please click search, then type in a couple keywords on what you are asking, and read up about your problem, then you wont have to put in the beginning of every thread you make "sorry guys, my parents should have used a condom, but heres a really noob question for you to waste some time on..."

Dude! This is a freaken Forum for God Sake!!! You know what? You're just messed up. Quit posting in my thread. If you're so sick of noobish threads like this, why don't you go post up a thread called quit asking noobish question or something like that got it pal? So back off.

MustGoFaster · 01-14-2006

I think he's just pissed because when ever he posted a question like this all he ever got was answers like he is giving you.