What RPM's are you guys running around 70mph?
 

Just wanted to know. I just picked up my first Miata and noticed I ws running around 3.5K around 70mph. Is that pretty normal? BTW it is a open diff from a 1.8. But that would'nt affect the ratio right?

In fif gear maybe 3.8k.

I run a little above 4K at 80, but I have an exhaust leak an no turbo.

...Please explain to me why that would have any effect on cruising RPM.

no

He's right Latena. The exhaust leak and being a non-turbo would certainly not have a effect on your cruising RPM's. This is solely responsible on your gear ratios. But you need to take care of that and get yourslef a turbo om that thing ASAP!

http://www.flyinmiata.com/tech/gearing.php

^ That many RPMs. ^

A friend of a friend of mine was convinced that he had to turn an extra couple hundred RPM to maintain speed in a headwind. Fuckin' drivetrains, how do they work?

:bowrofl::laugh:
http://s-ak.buzzfed.com/static/campa...71614310-3.jpg

no

???????? Jeff, classic pic man, classsic! I remember my ex-gf had a nephew who was so into ICP that he had a Eclipse that had a mural of there faces on the back window. I would never, and I mean never, let him park in our driveway!

This link misleads me to this conclusion:

Tire size: 275/75/18....Result: 2nd gear top speed: 94.7 mph...

It also says top speed in 5th gear is close to 220mph...

(OP should do this to achieve lamborghini diablo status)

Unsubscribed.

That's pretty screwed up and definitely not normal. I'm turning 85mph at 3500rpm.

Wow man seriously? I mean, I really thought it was a little high myself especially being a 5spd. I mean my wheels are 17's and the tires are 205 35's front and 245 35's in rear. So Now I will assume that my speedo is aboout 10mph off. That would put me in the range of about 3000rpm @7omph maybe?

Wrong. I get to about 3200-3500 around 70mph too...factory speedo will show about 73-74mph...and my brother's miata does about the same rpm's too...both are 1990 5-sp.

You're fine, if you're worried, get a 6-speed.

Only way I know how fast I am going is to take 5th gear indicated rpm and multiply by 2, then add a zero. Meaning 3k is 60mph, 3.5k is 70, 4k is 80, so on and so forth. So yeah, 3.5k at 70 is normal. Stock speedometers are not accurate down to single MPH's usually, so a few off is completely expected. Assuming you have the same rear gearing, my above should stand.

Okay that makes me feel alot better. Was just used to my 944 cruising 70@ 2500rpm. Although it's a 2.5 litre i was just curious to know if 3.5rpm's was average around 70mph for this car. I know they rev to keep highway speeds in check. And i do realize that teh average speed was 55 when this car was built. And few highways were still 60-65 at this time.

I'm at 75 at 4000 rpm in 5th

I'm at 7600 rpm at 74.38 mph.


Sorry, couldn't resist, I have been good all day, really I have.

2nd gear (5 spd), 275/35/15 tires, 3.63 rear end.

Whoa man!!! What the hell? 3.63's are causing this? Whats the factory ratio for a 92? Does anyone know?

I got warned because of this thread. So much win.

90mph = 4k, 6speed 3.9 with 225/50/15. that's all i know

Sorry, didn't mean to freak out the new guy.

If you read all the post, that's in second gear with an elevated rev limiter. It's a dedicated autocross car.

Your '92 came with a 4.30 rear end ratio.

With stock gearing and tires about the same diameter as 205/50/15s you would be around 3700 rpm at 70 mph.

The rpm, gear ratios, and tire diameter determine the speed. So unless your clutch is slipping or the tires are spinning, you will be traveling the same speed at the same rpm as everyone else's car with the same transmission, rear end and tire diameter.

The question I think you were trying to ask is "Is it normal for a Miata to rev that high on the highway?" The answer you should have gotten back was "Yes, you will notice that your Miata likes to be at a higher rpm for a given speed than some other cars you may have driven." Had they taken the answer a little further it would have gone something like this "If your car is up to date on it's maintenance and in otherwise good condition, you will not hurt the motor revving it even higher. In fact the closer to the rev limiter (and yes there is one to protect you) you get, the more responsive the car will seem".

Thanks Chris,

Yeah, i found that i have the 4.30 final drive. And i totally ignored where you did state that was in 2nd gear. So my bad man. I was not really that surprised to see around 3500 @ 70mph. It reminds me of my buddys Toyota Corolla Gt-s. That thing is screaming at 70, but its a 86. And i know about the tire/ wheel combo that would have a dire effect on the rpm at speeds etc. I just thought since i was running 17's that at 70 i would be a lil' lower that's all. And it seems that most people are saying around 3.5 is the norm.

So i am right up to par, thanks for the insight however.

Do not piss me off or I'll retrieve the ban hammer from the glass case.

n00bs pushin his luck, I say you own him

Will you use your dick to break the glass because you are that bad ass?

no he will grab Chuck Norris by the beard and sling him into the glass to brake it....

I m at 60 at 3000rpm...

3600ish i think?

2900 tach rpm.
3.63 with a 5 speed.

stock diff gear and 99 transmission on my rotary swap i'll be at 71.5mph at 8000 rpm in 2nd. :giggle:

and at 9700rpm redline in 2nd I'll be at 88mph, making approximately 1.21 jiggawatts to the wheels

Do you like the 3.636 with 5 speed? I am getting ready to go that route.

hella long gears.
i want 6 speed.


PS here is a vid of a 2nd and 3rd pull.
http://www.youtube.com/watch?v=Hp_T2_8j8To

longer gears = more load on the gears = they break faster

be careful