speed in 3rd gear
#53
Umm.... What a challenge to see speed without being on track.
I swear I've seen mine over 68 in second and I thought I have seen 103 in third before.
In fact I think I even posted 103 a couple of years ago.
Mines in the shop right now. And the body kit may make a differance.
I swear I've seen mine over 68 in second and I thought I have seen 103 in third before.
In fact I think I even posted 103 a couple of years ago.
Mines in the shop right now. And the body kit may make a differance.
#54
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My car is pretty much the same as yours Brett and i only get about 158km out of third 108km in second. its an 03 as well
The only mod i have is the racing beat air duct, but mods will only make you get there quicker. I don't think its a model difference
The only mod i have is the racing beat air duct, but mods will only make you get there quicker. I don't think its a model difference
#55
I never intended to imply that my car was faster or anything like that - just that it had a different 3rd gear ratio to others on the site.
Rotor man - try taking it to the rev limiter - bet you will get more like 165-170 km/hr .
Is yours a jap import as well ?
Rotor man - try taking it to the rev limiter - bet you will get more like 165-170 km/hr .
Is yours a jap import as well ?
Last edited by Brettus; 11-19-2006 at 02:41 PM.
#57
Originally Posted by rotor_man
yeah mines an imporrt. you might be right i will check it again though, i usually change 3rd at the beep not the engine kill.
Am trying to get some nz 8 owners together for a run around Pukekohe early next yr - you keen ?
#58
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There's a way to calculate the Speed vs. RPM, but you need to know several things first: tire size, final drive ratio, and the individual gear ratios for 1st through 6th gears. Use those values at the following URL to create a Speed/RPM table. You can then cut & paste it into something like MS Word or Excel and end up with something like the following table. I've checked it against real speed/rpm, and it's very accurate.
Speed/RPM Calculator
Speed/RPM Calculator
#59
Registered
Thread answered.
Just as I thought, the Japanese spec RX-8 S-Type, the high-powered 6MT version has 1.530 as 3rd gear ratio as opposed to US spec 1.645 to match the higher output of the Japanese version.
Image attached.
Thanks for sharing your observation Brettus!
Just as I thought, the Japanese spec RX-8 S-Type, the high-powered 6MT version has 1.530 as 3rd gear ratio as opposed to US spec 1.645 to match the higher output of the Japanese version.
Image attached.
Thanks for sharing your observation Brettus!
#60
Zoom-Freakin'-Zoom
iTrader: (5)
Originally Posted by dynamho
Thread answered.
Just as I thought, the Japanese spec RX-8 S-Type, the high-powered 6MT version has 1.530 as 3rd gear ratio as opposed to US spec 1.645 to match the higher output of the Japanese version.
Image attached.
Thanks for sharing your observation Brettus!
Just as I thought, the Japanese spec RX-8 S-Type, the high-powered 6MT version has 1.530 as 3rd gear ratio as opposed to US spec 1.645 to match the higher output of the Japanese version.
Image attached.
Thanks for sharing your observation Brettus!
beers
#61
Originally Posted by dynamho
Thread answered.
Just as I thought, the Japanese spec RX-8 S-Type, the high-powered 6MT version has 1.530 as 3rd gear ratio as opposed to US spec 1.645 to match the higher output of the Japanese version.
Image attached.
Thanks for sharing your observation Brettus!
Just as I thought, the Japanese spec RX-8 S-Type, the high-powered 6MT version has 1.530 as 3rd gear ratio as opposed to US spec 1.645 to match the higher output of the Japanese version.
Image attached.
Thanks for sharing your observation Brettus!
Can you tell me if all the other ratios are the same ?
I'm sure the stock HP is not 250 though . When it was stock on a Dyno Dynamics dynamometer (which reads low campared to Dynajet) it made 170hp to the wheels & talking to the operator this is pretty std for all the 8's he has tested here.
#67
Registered
Originally Posted by Brettus
Mazda Maniac
Another side effect is that you will depreciate your car faster because more revolutions mean more mileage put on your odo.
BTW, except for 3rd gear, everything else, including reverse and final drive are the same.
Cheers.
#68
Originally Posted by dynamho
Not exactly. Mazda_Maniac was right in saying that your smaller wheel setup gave you elevated speed readings, but if my calculations are correct, your speedo with your wheels is only around 2-4 mph inaccurate. It's significant, but not to the degree that you're talking about.
Cheers.
Cheers.
Yes my speedo will be inacurate - with smaller tyre I'll be going slower- but the speed readout will be the same for a given gear ratio & rpm no matter what sized tyre I have on .
Last edited by Brettus; 11-20-2006 at 07:51 PM.
#69
Registered
Originally Posted by Brettus
did you read the analogy I did of a car up on jacks with wheels not touching the ground ?
Originally Posted by Brettus
Yes my speedo will be inacurate - with smaller tyre I'll be going slower-
Originally Posted by Brettus
but the speed readout will be the same for a given gear ratio & rpm no matter what sized tyre I have on .
Remember, speedos detect revolution pulses. If the wheel is bigger, it will take a longer time to go around. If your wheels are smaller than stock setup, it will generate more revolution pulses than stock, which falsely elevates your speedo reading. That's as far as I'll go to try to explain it. Good luck.
#70
Originally Posted by dynamho
Remember, speedos detect revolution pulses. If the wheel is bigger, it will take a longer time to go around. If your wheels are smaller than stock setup, it will generate more revolution pulses than stock, which falsely elevates your speedo reading. That's as far as I'll go to try to explain it. Good luck.
So you are saying that ....... with smaller tyres, my speedo will read a higher number at 9000 rpm even if the wheels are off the ground and the car is stationary ?
I suspect you are not - what makes you think the number will be any different when the wheels are on the ground ??????
#71
Registered
On the ground or off the ground, wheel size doesn't matter Brettus. Your speedo will show you a speed reading as if it had stock wheels on even if you're spinning nothing but your axle or a monster 21 inch bling chrome.
#72
Yes - correct . I think we are on the same wavelength now .
I thought you mean't by the "falsely elevates your speedo reading" comment that the speedo would read higher (at 9000rpm) with smaller wheels .......
I thought you mean't by the "falsely elevates your speedo reading" comment that the speedo would read higher (at 9000rpm) with smaller wheels .......
Last edited by Brettus; 11-21-2006 at 12:45 AM.
#73
Registered
Imagine that you're on 3rd gear at 9000RPM and your speedo says 100 mph.
Oh snap, you realize that your car is on jack stands. What's your real speed Brettus? Isn't it zero mph? You're not going anywhere, but your speedo says you're going 100 mph. It's falsely elevated, isn't it?
Oh snap, you realize that your car is on jack stands. What's your real speed Brettus? Isn't it zero mph? You're not going anywhere, but your speedo says you're going 100 mph. It's falsely elevated, isn't it?