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Discussion Starter · #1 ·
Does anyone that does logging have an idea what speed they are going at the 60 foot mark?
I know it is not an X=Y deal but I am trying to figure something out.
Thanks
 

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Does anyone that does logging have an idea what speed they are going at the 60 foot mark?
I know it is not an X=Y deal but I am trying to figure something out.
Thanks

Well at a 1.62 second 60ft time = something like 38.4 mph
60 feet is roughly 3 car lengths.


Convert the 1.62 Seconds to Minutes to Hours
Convert 60 feet to Miles
Miles/Hour
 

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Well at a 1.62 second 60ft time = something like 38.4 mph
60 feet is roughly 3 car lengths.


Convert the 1.62 Seconds to Minutes to Hours
Convert 60 feet to Miles
Miles/Hour
The process of converting "60'/1.62sec" would yield the AVERAGE mph over the 60 foot span assuming zero acceleration. This will not be accurate. Plus, the conversion of 60'/1.62s is 25.25 mph.

If you are willing to "assume" constant acceleration (which this is not), the basic physics kinematic equations for constant A can be used. I can do this math if wanted, but will be a rough approximation/guess at best, and likely not accurate at all.
 

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Assuming a constant acceleration, basic calculus position formulas give 46.4 mph for your 1.76 60'.
But....especially for a non-abusive clutch car launch, acceleration will be far from constant. If you remained in 1st gear through the 60', I would think your acceleration was lowest leaving the line and near peak crossing the 60' mark (assuming you were near your power peak there too). That logic says your speed should be slightly higher than 46.4.
I wouldn't trust something like Datamaster for the speed; it's changing too fast for the sampling rate.
 

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Assuming a constant acceleration, basic calculus position formulas give 46.4 mph for your 1.76 60'.
But....especially for a non-abusive clutch car launch, acceleration will be far from constant. If you remained in 1st gear through the 60', I would think your acceleration was lowest leaving the line and near peak crossing the 60' mark (assuming you were near your power peak there too). That logic says your speed should be slightly higher than 46.4.
I wouldn't trust something like Datamaster for the speed; it's changing too fast for the sampling rate.
At 660 foot mark my car hits 80+ mph most of the time.
Best has been 8.11, lots of 8.20 all in hot weather.
Best of 12.88 103.40 also it the heat at Capitol Raceway.
So a plot can be estimated on rate of acceleration.

There is a new Camera that can track our runs.
Need to get one.




Dan
 

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Gerry, I've been watching this since begun, and still not confident I know what you're after with the programming angle I googled and read 'acceleration' per se for cars is pretty much linear just off-line as Mr. -Terror mentions, but changes to a curve soon after based on many components to arrive at the 1/4 mile time/speed. (wt., hp, gears, drag). We have your 550hp, plus T56 gears, so are you looking for baseline program values from some smart tuner guy to improve slightly on the ET/speed numbers in your sig? ::confused as hell smilie::
 

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Discussion Starter · #8 ·
As Pat and Johnathan point out, this would never be a constant accel, so every car would be different for a given 60 foot time. I was trying to get an idea of peoples speeds at the 60 foot mark.

Mine , is possibly a case even further from the norm as Pat points out.
Babying (by drag race standards ) out of the hole then pulling right through the RPM range in the 60.

This is why I was asking if anyone logs this stuff in race cars.
My world of road racing , the info is there to be had as we log a ton of crap at over 100 times a second ,

Where was all this going??

This started from conversations that had comments like " it looks like it is leaving really well, why is your '60' so crappy?"

I was looking at videos I have of the car from outside and in and started wondering if I am shifting or starting to shift before hitting the 60 foot lights.
No this is not a big issue for an auto,,,,, or Ronnie Sox (rip)
My set up will only go 39 at shift, 40 at limited 7100

Now granted, if I shift at 59 feet or 61 feet, the 1/4 ET will not change, just the 60 foot ET number

So this really is a moot point

Thanks for the input
 

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Well Alrightee Then -

Thanks for the fast back. I watched several of your vids before (neat road racing too). You seem to shift long after the lights tell you, but I pretty much discounted that based on your driving/times otherwise. If you're not shifting before 60' then everything's more a factor of reaction time and hookup. Well, plus maybe revs and gears.

Now that we know what you're after maybe the racers (especially the guys ragging on you ;) ) can offer actual ideas on reducing your offline.
 

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Gerry,
Don't confuse 0-60 mph time with 0-60 foot time.
Where your shift occurs has very little to do with 60' time, and just about zero to do with ET.
It has a big influence on 0-60 mph time, but I don't think you really care about that.
 

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Discussion Starter · #12 ·
Gerry,
Where your shift occurs has very little to do with 60' time, and just about zero to do with ET.
Pat, you have done this a lot more than me.
Please explain.
I get that it will make basically zero difference to 1/4 ET or 1/4 MPH as I am going to make the 1-2 shift at some point always and always around that point.
What I don't get is how completely taking the power off ,then putting it back on before the 60 foot timer would not adversely affect the 60 foot et.

What would happen to your 60 foot time if you took your foot off the gas for a moment before the 60 foot on a pass?

While , with my car, it ultimately makes no difference to how it gets to the other end , what got me thinking was the the car feels to be leaving well, but the 60 foot times are 2 tenths slower than when it was a mild 350 automatic.
That and remembering reading about the Z06 0-60 mph road test times were said to be so good partially due to they didn't shift before 60 mph
Thanks, Gerry
 

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Pat, you have done this a lot more than me.
Please explain.
I get that it will make basically zero difference to 1/4 ET or 1/4 MPH as I am going to make the 1-2 shift at some point always and always around that point.
What I don't get is how completely taking the power off ,then putting it back on before the 60 foot timer would not adversely affect the 60 foot et.

What would happen to your 60 foot time if you took your foot off the gas for a moment before the 60 foot on a pass?

While , with my car, it ultimately makes no difference to how it gets to the other end , what got me thinking was the the car feels to be leaving well, but the 60 foot times are 2 tenths slower than when it was a mild 350 automatic.
That and remembering reading about the Z06 0-60 mph road test times were said to be so good partially due to they didn't shift before 60 mph
Thanks, Gerry

FWIW my 60 ft time dropped a little when the driver side gets some air.
More 1,67, 1.66 and 1.65 times up 1 or 2 hundredths..


D
 

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...Please explain.
I get that it will make basically zero difference to 1/4 ET or 1/4 MPH as I am going to make the 1-2 shift at some point always and always around that point.
What I don't get is how completely taking the power off ,then putting it back on before the 60 foot timer would not adversely affect the 60 foot et.

What would happen to your 60 foot time if you took your foot off the gas for a moment before the 60 foot on a pass?

While , with my car, it ultimately makes no difference to how it gets to the other end , what got me thinking was the the car feels to be leaving well, but the 60 foot times are 2 tenths slower than when it was a mild 350 automatic.
That and remembering reading about the Z06 0-60 mph road test times were said to be so good partially due to they didn't shift before 60 mph
Thanks, Gerry
Let's assume you're at 50 mph at 50' out and 1.5 sec has elapsed.
Take your foot off the throttle and you'll cover that remaining 10 feet at ~50 mph (73 fps)..... adding 0.14 sec, giving you a 60' time of 1.64 sec.
Next pass, stay in the throttle, and assuming a 60' speed of 56 mph, the remaining 10 feet is covered at an average speed of 53 mph (77 fps).... adding .013 sec, giving you a 60' time of 1.63 sec.
It's not a zero difference of course, but as I said it has VERY LITTLE effect.

Comparing your 6-spd 60' to your previous auto 60' points out the advantage of a torque converter .....maximum tractive force the instant you hit the throttle, PLUS torque multiplication of up to 2.5X engine torque with a really good converter. Just as the ET is all about the 60', the 60' is all about the first 2 feet! You're not "feeling" what you're missing in those first few hundredths of a second covering that 2 feet ;)
A manual trans car that is at all streetable and not purposely built to take severe abuse will never have a chance in 60' time against a similar car with a GOOD TC / auto trans.
 

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