No, the speedomotor reads the amount revolutions per unit time and converts that into a speed based on the assumed tire size. A smaller wheel/tire combination would correspond to the car going slower than the speed indicated whereas a larger wheel/tire combination would be going faster. The speedometer does not account for changes in wheel/tire size.
What have you done to your MSP today?
- Thread starter baconbitz
- Start date
foreverzero89
Member
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- 03.5 'speed protege
as i said he couldn't have gone that fast without changing the gearing, which he did and prob bouncing off the rev limiter too.
Wagonbacker9
Member
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- 2004 'Hoe
we're having a language barrier here. You basically just said the same thing I did, from the opposite perspective.
I'm saying the speedo reads higher than actual with a smaller tire
You're saying the actual speed is "slower than indicated" with a smaller tire.
http://www.miata.net/garage/tirecalc.html
Stock is 215/45/R17.
This is 4.8% smaller than the stock tire being calculated by the speedo (I misspoke earlier about the difference) gives me a 57.1mph real speed when my speedo reads 60 (assuming that both the origional and in use tire sizes are calculated perfectly)..
I'm saying the speedo reads higher than actual with a smaller tire
You're saying the actual speed is "slower than indicated" with a smaller tire.
http://www.miata.net/garage/tirecalc.html
Stock is 215/45/R17.
This is 4.8% smaller than the stock tire being calculated by the speedo (I misspoke earlier about the difference) gives me a 57.1mph real speed when my speedo reads 60 (assuming that both the origional and in use tire sizes are calculated perfectly)..
He did not change the gearing - he is running the stock gear ratios and was basing this off the stock speedo - the same one you're using. If anything he's running a 215/35R18 tire which makes it a little smaller than stock. So actually he was probably going 1-2 mph slower than his speedo reading.
The math does not lie: http://www.mazdas247.com/forum/showpost.php?p=1446673&postcount=21
As you can see these cars are geared for upwards of 160+ mph but in order to reach it you need sufficient power and you need to remove the speed limiter (the existence of this is debated). I know this is not the exact stock wheel diameter but the calculations can be easily re-run to prove that these cars are NOT gear limited to 135 mph.
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Gotcha... I was just getting thrown off when you said "the speedo is reading higher"
hahaha
yea mazdaspeed2oo3 is running a haltech standalone, so no speed limiter...when youve got 475ish whp to the ground you'd be surprised what you can do
(plus if I recall he raised his rev limiter to 7500 from 6500, which helps a LOT with this)
he is a bad example to relate to the rest of us lol, he's done everything to his car and then some...
yea mazdaspeed2oo3 is running a haltech standalone, so no speed limiter...when youve got 475ish whp to the ground you'd be surprised what you can do
(plus if I recall he raised his rev limiter to 7500 from 6500, which helps a LOT with this)
he is a bad example to relate to the rest of us lol, he's done everything to his car and then some...
^^^ Still, look at the link I posted. Rogue did the calculations at 7200 RPM, which is around where the stock rev limiter is (7250 RPM, I believe). With enough power and no speed limiter these cars should be able to hit 160+ mph. Not that you'd ever really be able to do that.
Wagonbacker9
Member
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- 2004 'Hoe
bonneville salt flats anyone?
Ricktalife
Member
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- 2012 Subaru WRX
haha i like that one.
exactly my point lol
foreverzero89
Member
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- 03.5 'speed protege
to Mazdaspeed2oo35: holy freakin crap your car is awesome, and in the best color too! but i don't think the best looking wheels for this car are the rx-8, sorry.
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Velocifero
Wham Bam thank you Ma'am
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- VRM MS6, Sunlight Silver MSP
She's running again. Good to have her out on the road again, a month and a half is a long time. Once I dropped her to the ground yesterday she wouldn't turn over. I started getting pissed then I realized I didn't cycle the alarm and the security ignition switch was doing it's job. Then I blew the cold pipe off the TB coupling on the test drive, no biggie. Runs good and the tranny seems to be holding its own, we'll see how long that lasts. I removed my ksports and put on a set of HPs with Stech springs. Way more comfortable and still a nice ride height. I have all new hardware coming for my AWR rear sway so I can get that back on and noiseless. I didn'y get to install my alcohol injection kit so I think I'll wait til I change over the IM. I got the front facia to sit a lot cleaner this time since after the FMIC install. She is looking good now I just need to clean her up and get some new pictures of her.
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- 03.5 YLW MSP
Cleared p0660 and P2006 cels again! fun fun
Mazdaspeed2oo35
600whp - 600wtq at 30 PSI
Thank you guys for those kind of words, they are highly appreciated and mean a lot. about the speedometer of our cars they are very very accurate, when i took my car to the dyno, the guy actually ask me for the wheel and tire size and input it to the machine to get the right speed and power readings, while at the dyno the car did 474whp at 25 PSI with a huge Vac leak and heat soak under the hood the car hitted a top speed of 274.2 kph at 7498 rpm that's equal to 170.38 Mph at 7498 rpm these cars are not gear limited to 135-160 mph, rising the rev limiter and having enough HP under the hood you can hit enough top end in these cars. lot's of you will ask how the hell can you go that fast on a dyno when you dyno the car in 4th gear, well we had to dyno the car in 5th gear because at 4th car were breaking loose spinning tires like a mofo at the rolls, not even Coca Cola or Pine Apple juice they trew at the rolls helped to get traction i also do believe this car have over 500whp do to the fact of having a huge vac leak and heat soak car was able to hit 474.8whp. You can also notice turbo didn't kicked in until 100 mph and some of you might have said damn that s*** is laggy, well car is not laggy at all is just that putting your car in 5th gear at around 65 mph and just press the gas pedal the turbo will take longer to spool but as you saw in the video when it did it was incredible and amazing, in real life and car pulling its own weight the speedo don't move that fast but it pulls fast enough to make you s*** in the pants. i still see people that don't believe in these cars capabilities, these little cars with some money and good parts and tune can turn out into some bad mean machines. I still remember my friend's face when i beat him from a 75-170 race on his Gallardo there is no money or any other car that can pay or satisfy me the way this car have done, beating others cars that double, tripple and 10 times more expensive. So based on my experience these cars are not gear limited to 135 mph or 160, because i have gone over that speed on the dyno and in a private road when my gps said 170 mph also there is the dyno video where you can see the needle going all the way down to the Odometer is..
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foreverzero89
Member
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- 03.5 'speed protege
what head work have you done to make revving that high safe?
just about everything you can think of, I can also attest to these cars not being gear limited to 135, i still had my topspeed limiter but it got up there damn quick, i could have gone way over without much effort, one day I'll buy another MSP, that's why I still hang around
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TheDirtyGoatee
Member
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- 2008 Mazda MX-5 5MT PRHT
Want a Spicy?! LoLz
Wagonbacker9
Member
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- 2004 'Hoe
I painted my (lightly corroded) front emblem semi-gloss black over the weekend. Rear center and "protege" emblems to follow... though they seem to be FIRMLY stuck on there...
hopefully I should have everything blacked out in time for the summer wheels to go back on.
hopefully I should have everything blacked out in time for the summer wheels to go back on.
