my 155mph miata
#8
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Definitely don't need 360whp to go 155mph. My 320whp car would pull 3.63s hard into the 7400rpm limiter at ~152mph GPS.
Keep in mind that tire diameter fluctuates dramatically at high speed. 7400rpm with 3.909s and a 6-speed calculates to ~154mph, but if you actually try it, the GPS will say ~146mph.
Keep in mind that tire diameter fluctuates dramatically at high speed. 7400rpm with 3.909s and a 6-speed calculates to ~154mph, but if you actually try it, the GPS will say ~146mph.
#9
With 205/50R/15, 6speed, 3.9, and stock 7200rpm rev limiter, you can do 250kph. So, 7538* rpm for 254kph. With a 5speed, it's 7278rpm. So, my new guess with actual maths is 5speed and 3.9.
#11
I can gear out my T25 200whp setup easily in 5th gear with a 4.30 at 7400rpm, at an indicated 142mph (233.36kph) on 195s. While it's a sweet video, it isn't really an indication of mad power.
With 205/50R/15, 6speed, 3.9, and stock 7200rpm rev limiter, you can do 250kph. So, 7538* rpm for 254kph. With a 5speed, it's 7278rpm. So, my new guess with actual maths is 5speed and 3.9.
With 205/50R/15, 6speed, 3.9, and stock 7200rpm rev limiter, you can do 250kph. So, 7538* rpm for 254kph. With a 5speed, it's 7278rpm. So, my new guess with actual maths is 5speed and 3.9.
#12
Agreed, I made some rough assumptions on frontal surface area, Cd, weight, Crr, Fuel energy density, Drivetrain efficiency (95%), Engine efficiency.
From Race Technology Knowledge Base | M / Mazda
94 Miata CD 0.38, frontal area 1.71 sq m, CDa 0.65
Gearing is one thing having the power to overcome aero drag and reach the gear speed is another.
For my car last time I did coast down tests I got Drag coefficients for a given Wing Angle (frontal area of 2.1 sq m):
00 Deg: 0.25293
05 Deg: 0.36337
10 Deg: 0.34050
Plugging my setup into the formula I would need 300 RWHP to get to 155 mph (wing at 00).
From Race Technology Knowledge Base | M / Mazda
94 Miata CD 0.38, frontal area 1.71 sq m, CDa 0.65
Gearing is one thing having the power to overcome aero drag and reach the gear speed is another.
For my car last time I did coast down tests I got Drag coefficients for a given Wing Angle (frontal area of 2.1 sq m):
00 Deg: 0.25293
05 Deg: 0.36337
10 Deg: 0.34050
Plugging my setup into the formula I would need 300 RWHP to get to 155 mph (wing at 00).
#14
Hey guys,
some answers:
- transmission is 6speed with 3.6torsen (from a 10th anni edition) (I think this is a great gear ratio step up for the car; gears 1-4 are nearly the same like 5speed with 4.3end)
- setup: 1.6 stock engine, 10psi, GT2560R
- last dyno was 222hp at flywheel, and 190rwhp
- the car was still accelerating, but then a idiot block the left lane, so I had to brake and slow down
- and yes video was filmed on autobahn, so all legal
I meassured 862°C after turbo and 970°C at the collector in the exhaust manifold before turbo at that high speed . All cool I think, what do you think?
Best regards!
Basti
some answers:
- transmission is 6speed with 3.6torsen (from a 10th anni edition) (I think this is a great gear ratio step up for the car; gears 1-4 are nearly the same like 5speed with 4.3end)
- setup: 1.6 stock engine, 10psi, GT2560R
- last dyno was 222hp at flywheel, and 190rwhp
- the car was still accelerating, but then a idiot block the left lane, so I had to brake and slow down
- and yes video was filmed on autobahn, so all legal
I meassured 862°C after turbo and 970°C at the collector in the exhaust manifold before turbo at that high speed . All cool I think, what do you think?
Best regards!
Basti
Last edited by Mazdaspeed_Miata; 06-16-2015 at 06:50 AM.
#19
OP: Haben Sie aerodynamische Abaenderungen gemacht?
#20
Well, I won't say that it feels very comfortable past 120mph, but in my own sensation it is still ok. My biggest fears are that I have to do an emergency braking from high speed (because i have no ABS) or that the engine blows away at that speed. The feeling inside of the car without any problems is ok. Only the wind noice gets pretty loud at that speed
Again my question:
I meassured 862°C after turbo and 970°C at the collector in the exhaust manifold before turbo at that high speed . All cool I think, what do you think?
And I have no aerodynamic specs, only the factory airdam at the front.
Here 4 pics of my miata:
<a href="http://www.directupload.net" target="_blank"><img src="http://fs2.directupload.net/images/150616/yqwidcl5.jpg" title="Kostenlos Bilder und Fotos hochladen"></a>
<a href="http://www.directupload.net" target="_blank"><img src="http://fs2.directupload.net/images/150616/ehl9luko.jpg" title="Kostenlos Bilder und Fotos hochladen"></a>
<a href="http://www.directupload.net" target="_blank"><img src="http://fs1.directupload.net/images/150616/owka3uam.jpg" title="Kostenlos Bilder und Fotos hochladen"></a>
<a href="http://www.directupload.net" target="_blank"><img src="http://fs1.directupload.net/images/150616/caqr3hcv.jpg" title="Kostenlos Bilder und Fotos hochladen"></a>
Again my question:
I meassured 862°C after turbo and 970°C at the collector in the exhaust manifold before turbo at that high speed . All cool I think, what do you think?
And I have no aerodynamic specs, only the factory airdam at the front.
Here 4 pics of my miata:
<a href="http://www.directupload.net" target="_blank"><img src="http://fs2.directupload.net/images/150616/yqwidcl5.jpg" title="Kostenlos Bilder und Fotos hochladen"></a>
<a href="http://www.directupload.net" target="_blank"><img src="http://fs2.directupload.net/images/150616/ehl9luko.jpg" title="Kostenlos Bilder und Fotos hochladen"></a>
<a href="http://www.directupload.net" target="_blank"><img src="http://fs1.directupload.net/images/150616/owka3uam.jpg" title="Kostenlos Bilder und Fotos hochladen"></a>
<a href="http://www.directupload.net" target="_blank"><img src="http://fs1.directupload.net/images/150616/caqr3hcv.jpg" title="Kostenlos Bilder und Fotos hochladen"></a>