High RPMs

Danny · Post by **Danny** » February 26th, 2006, 8:51 pm

Ok, so I'm driving in 1st, I shift at 3K, and my RPMs go to 2250~, and same for 2nd, 3rd, and 4th. And when it does it in 4th, that means at 3K RPM in 5th, I'm sittin at 64 MPH.... I mean, I thought shifting into 5th was supposed to significantly drop your RPMs, like 2K~, not 600. I mean, when I get on the highway, and I'm going about 70 MPH, it sounds like my engine is about to blow up its revving so high, I mean, I cringe whenever I go any speed above 70 (note, I'm not specifically talking about 70MPH, I'm just saying that once I get going at high MPH its at very high RPM). In my old civic (it was auto...if that matters), I would get up to 100 MPH on the highway and it wouldn't even phase me.
Is something wrong with my car, or is it just me?

BTW, I do have a POS exhaust, its like all rusted and corroted, there's also a big ol hole in my cat. My friends grandpa said that replacing it would help, he said something about back pressure...any ideas?

SBmx3 · Post by **SBmx3** » February 26th, 2006, 10:25 pm

when did the problem start? has it always been like that?

atlantamx3 · Post by **atlantamx3** » February 26th, 2006, 11:01 pm

You can thank the lovely engineers at Mazda for the gearing ratios on your tranny.

Its normal for MX-3's to rev high like that, even in 5th gear at highway speeds.

Sucks, doesnt it?

Danny · Post by **Danny** » February 27th, 2006, 10:35 am

SBmx3 wrote:when did the problem start? has it always been like that?

Yeah, its been like that every since I got it, in like October/November.

You can thank the lovely engineers at Mazda for the gearing ratios on your tranny.

Its normal for MX-3's to rev high like that, even in 5th gear at highway speeds.

Sucks, doesnt it?

Soooo.....basically I'm screwed.....and there's nothin I can do about it.....

Bochek · Post by **Bochek** » February 27th, 2006, 3:42 pm

correct, there are 2 reasons why they do this...

These motors will run for longer at these rpm's (less of a load on the engine) and they are more fuel efficiant at right around 3k pushing little load compared to 2k pushing more of a load.

Bochek

Tunes67 · Post by **Tunes67** » February 27th, 2006, 5:23 pm

These motors will run for longer at these rpm's (less of a load on the engine) and they are more fuel efficiant at right around 3k pushing little load compared to 2k pushing more of a load.

Thats a nifty theory

Except the engines in our cars are pulling loads and not pushing them LOL

Tunes67

Bochek · Post by **Bochek** » February 27th, 2006, 5:27 pm

Tunes67 wrote:
These motors will run for longer at these rpm's (less of a load on the engine) and they are more fuel efficiant at right around 3k pushing little load compared to 2k pushing more of a load.
Thats a nifty theory Except the engines in our cars are pulling loads and not pushing them LOL

Tunes67

Stupid FWD

D323 · Post by **D323** » February 27th, 2006, 6:10 pm

Actually you can do something about it.

Go to a junk yard and get the 5th gear from a DX protege... its a lower gear and you will see a more significant drop in the RPM's.

Bochek · Post by **Bochek** » February 27th, 2006, 6:34 pm

D323 wrote:Actually you can do something about it.

Go to a junk yard and get the 5th gear from a DX protege... its a lower gear and you will see a more significant drop in the RPM's.

not that great of a drop.. the difference is the protege dx does 3k at 120km/h and ours dose 3k @ ~105kmph

Woo!

Bochek

DJGypsy · Post by **DJGypsy** » February 27th, 2006, 6:56 pm

i think the ratios are fine the way they are, but a 6th gear would be great for higher freeway speeds. most freeways down here in FL have the limit posted to be 70. of course nobody is doing under 75. a 6th gear would be great for this to keep the engine around 3-3.5k as opposed to 4k+.

Danny · Post by **Danny** » February 27th, 2006, 7:11 pm

Bochek wrote:
D323 wrote:Actually you can do something about it.

Go to a junk yard and get the 5th gear from a DX protege... its a lower gear and you will see a more significant drop in the RPM's.
not that great of a drop.. the difference is the protege dx does 3k at 120km/h and ours dose 3k @ ~105kmph

Woo!

Bochek

Wait, how many MPH is 105 KMPH?

Oh, and if I do an engine swap, will that effect it at all?

Bochek · Post by **Bochek** » February 27th, 2006, 8:47 pm

65mph for your american people.

and no a engine swap wont make a difference. None. at all. But your car might be faster.

Bochek

Danny · Post by **Danny** » February 27th, 2006, 9:45 pm

Bochek wrote:But your car might be faster.

No way

corbanbrook · Post by **corbanbrook** » March 2nd, 2006, 12:59 pm

Would it be possible to upgrade to a 6-speed? or would that be costing to much money for it to be worth it.

Devilhog · Post by **Devilhog** » March 3rd, 2006, 12:36 am

Is there a 6 speed that will actualy bolt up to our engines?

Anyways at 70mph my car is doing 3200 rpms. I dont see much of a problem with that.

You guys need to start driving the car, not baby'ing them. Have fun take it above 5000 every once and a while

And to those who dont baby their cars, cya on the road

Got my Stock 96 1.6l Dohc up to 210 kph. Cant wait to see it once I get some work into the engine.