Well, there is of course speedo error, including the effects even a small tire pressure change could have. A 2% error would just about cover the discrepancy, but that boy was flying, no doubt.
And modern electrical speedos are much more accurate - you will not see 10% errors. My 1992 LT1 Vette was accurate to 1mph against a calibrated 5th wheel at 120!
http://www.mn12performance.com/mn12-techinfo/tsb/tsb-89-02-07.pdf
If the 3.75% high factor stated in the link stands, it would explain the discrepancy precisely. 155 + 3.75% = 160.8 mph
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Originally posted by ALLNTRL
If you think 160 MPH is fast in your car (which it is, no flame intended) try running 180 MPH on a bike!!!
Or how about 120 a 1/2 inch off the ground in a five-speed go-kart. Not to mention cornering at 2.5 g's.
I'll do that, and I'll also use my Garmin GPS to see the true top speed it will do.. (also use to compare the speedo readings all through the range)...
any updates?? wheres the video??
B
blown03cobra
Guest
evilcartman is out of town,,, this is an old camcorder and he has the wire to upload it to his computer so there is not really much i can do.... unless i get a tick and get my sony dsc and make an mpg and have someone host it.... I might do that today if it doesnt rain
Speedn88Stang
New Member
Way to go Nic...Havent you already wrecked the car once and now you are doing this bullshit after just getting it? Keep doing it. Im waiting for you to hit a pot hole or have to swerve for some reason. damn you are a jackass! I dont even know if i would trust you at a closed track. Geez. Good luck in life being a spoiled brat!:loser:
*edited by Moderator - Keep the flames in Smack Down
*edited by Moderator - Keep the flames in Smack Down
:bored:
sohowcome
Captain Obvious
LOL
Nic,
Why do you have to be so hard on cars???
Is this becomming something we(03 owners) are striving for?
Is it going to take a fatality to re-gain our focus on performance and making our cars better at the track, not just seeing how fast we can go on the street? I may be wrong about this and it's just my opinion, but I'd be willing to bet that if you're posting here on SVTPerformance that your REAL job description doesn't include the words "NASCAR", "Winston Cup" or Busch Series". We need to take care of each other and not applaud this wreckless driving. I. for one, don't want to read about your beautiful car splattered all over, let alone loss of human life. Take Care. It's all just my $.02 worth!
Is it going to take a fatality to re-gain our focus on performance and making our cars better at the track, not just seeing how fast we can go on the street? I may be wrong about this and it's just my opinion, but I'd be willing to bet that if you're posting here on SVTPerformance that your REAL job description doesn't include the words "NASCAR", "Winston Cup" or Busch Series". We need to take care of each other and not applaud this wreckless driving. I. for one, don't want to read about your beautiful car splattered all over, let alone loss of human life. Take Care. It's all just my $.02 worth!
Originally posted by sohowcome
YOu gotta remember that speedos, can be off by as much as 10% at high speeds 160*.10%=144 mph or even 5% would be 152 mph, still very very fast, I bet you were in the neighbor hood of 150-155, just a guess though.
-Zach
BTW those are some big balls you got there
10% could also be 176 or 5% be 168. Where is the rule that says all inaccuracy has to be a false high reading? Most recals for tickets show them to read low. Maybe it's just fairly accurate.
[soapbox]
The thing is, snake...we won't read about it. There will be people, soon, who will disappear from this board and will never be heard from again. Unless, of course, someone happens to live in the same town and reads the obits, and reports back.
Just like a couple street racers who took each other out last night, but nearly got some bystanders here in Asheville on Patton...don't take me or my family out due to reckless behavior.
No flames necessary.
[/soapbox]
Usually, the new electronic speedos are quite accurate, but the mfr's often dial in "error" to suit their purposes - I am told BMW reads high to keep their owner's out of reckless driving citations.
Even if that is just Internet BS, keep in mind also that an electronic speedo gets its cues from a VSS (vehicle speed sensor), which is simpy a device that puts out an electronic pulse every time a unit of rotation is determined. That is then sent to a computer which determines speed, and sends the appropriate signal to the electronic speedo. I do not have a schemtaic of the C0bra system so I cannot stak my rep on its approach, but I am guessing it is similar.
Now, the VSS is still subject to mechanical factors which can put it off. But in my Corvettes, the speedo was accurate to 1 mph, even at an indicated 154, the fastest I ever went in my Z07.
Even if that is just Internet BS, keep in mind also that an electronic speedo gets its cues from a VSS (vehicle speed sensor), which is simpy a device that puts out an electronic pulse every time a unit of rotation is determined. That is then sent to a computer which determines speed, and sends the appropriate signal to the electronic speedo. I do not have a schemtaic of the C0bra system so I cannot stak my rep on its approach, but I am guessing it is similar.
Now, the VSS is still subject to mechanical factors which can put it off. But in my Corvettes, the speedo was accurate to 1 mph, even at an indicated 154, the fastest I ever went in my Z07.
Cobra 03,
Maybe I'm wrong (and you would be the guy to know), but don't most speedo's use driveshaft rotation speed as the speed indicator? One way or another, aren't nearly all of them using the rotation of the wheel to determine the speed? This has always bugged me, but if this is true, wouldn't the treadwear on your tires actually affect the accuracy of the speedo, especially at high speeds?
Yes, they do - that is where the VSS usually is.
And yes, it is affected by mechanicals as you state;
And tire pressure, and ambient temperature, and mold variations, and diameter/circumferential variations from mfr to mfr. Not to mention parallax error - you are reading an analog display at spped - who knows where the needle was releative to the sightline?
It is amazing that anyone would categorically state that the 155 mph limiter is wrong based on an entirely unscientific, field "experiment". Cheesh, don't they teach the scientific method anymore in schools? ;-)
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