Supra acceleration times

I know everyone gets sucked into 1/4 mile and 0-60mph times but these don't really do it for me because they both involve a standing start - since I don't "drag race" or do the "traffic light gran prix" they aren't really directly usefuly figures for on the road real world performance. Ok you can infer stuff from them, but does anyone have any other type of measurement?

For example, what is a good say 40 to 90mph time in a standard/BPU/APU car?

I recently (using a digi camera) got a rough time of about 5 seconds to get from 40 to 90mph in 3rd gear alone (ok I could do this quicker if I used 2nd to get to ~60mph) but I though this is a good measure of the overall pulling power of the engine (i.e its low down torque and peak power - and the spread of the power over the rev range).

Does anyone have any similar measurements which which I could compare?

all intermediate 1/4 times seem to be based on distance and unless you are on the strip all the time this is not an easy measure to gauge the current performance of your car against...

Agreed. I think these are much more interesting than qtr mile times. I doubt you'll get accuracy greater than one second based on your car speedo though. I recorded these times for my supra with an accelerometer:

60-100 mph 6.1 secs

30-70 mph 3.8 secs

I also plotted this graph of some of my cars:

http://www.compsoc.man.ac.uk/~jamesg/misc/CARS.gif

Is there such a thing as a 1 mile run?

Not sure where this could be done!! But the Supe would rule at it!!!

40-100mph is a good one.

Fast cars do this in 8secs or less

But yeah, it has to be measured automatically, without reliance on the speedo or someone pressing a timer button.

To me this is much more interesting that 0-60 or drag runs.

After all when you want that extra power on tap you're always doing a bit of speed already.

Agreed, racing from a roll is always going to be a better indication of a cars power and aerodynamics as you dont have to worry about grip as much as you do launching from the line

yeah exactly! I'm glad I'm not the only one thinking this then!

I might time a 40 to 100 run then, see if I can beat the 8 seconds, as I say my 40-90 was around 5, seems reasonably good but I have little to nothing to compare against at the moment.

It's so true that 99% of the time, you are already moving when you need to go flat out. Often it's less lag and a wider power band (power when you need it) that makes you quicker on the road/track.

Has anyone else got any in car footage of their acceleration that I can compare against?

Has anyone else got any in car footage of their acceleration that I can compare against?

http://www.ian.chisholm.clara.net/downloads/singletest_short.mpg

The digital speed reading is in MPH and it is GPS accurate as it tallies exactly with my Road Angel II. 1.2bar, haven't done one at 1.4bar yet

-Ian

wow ouch I think your car would kick my cars ass, but then you do have a single! I need to line the videos up closely but your clearly quicker to 90 (when my footage ends), as would be expected

Need more to compare against

JamesG, what accelerometer are you using and do you recommend it?

Recently at an airfield driving day we did both standing start runs down the full length of the runway and rolling runs. On the rolling runs even the solitary bike that was there (a 700 summat or other) got shown my arse much to his surprise. The bike was the only thing that didn't get shown my back end from a standing start. The closest car to me was an fq300 upgraded to 350. The caterham that came at the end was very disgruntled when he tried to go up the inside of me at the top of the runway when I not only held him off on the outside line and then proceeded to annihialate him good and proper (I think up to 80 he thought he had a chance I showed him quite firmly that he didn't).

My terminal speed before breaking was recorded as being 146 mph by the police radar gun they had which I had down as 147 on GPS. I later recorded 153 with the roof off and the windows down and 156 with the roof off and the windows up. I reckon with the roof on and a bit more confidence in my braking zone I'd have managed 160. The runway was about a mile long with 90 degree taxi ways at each end.

JamesG, what accelerometer are you using and do you recommend it?

Chilli - It's a Race Technology AP22. It works fine. I'd rather "recommend" accelerometers produced by the company I work for, but they're a bit more expensive

Ian - Your car is NUTS!!!!! I want a single!!

Ian C, just had a play with virtual dub video editing software, I cropped your video and mine to show a 60-90 blip and then used the video timeline and freezeframe to measure the times, the figures were:

Yours = 3.033 sec

Mine = 3.360 sec

But you did a gear change just before 90 and I did not, I suspect that means you are another few tenths quicker still so probably in total at least half a second or more quicker, which is quite a lot really - I need that single

Also my speedo is not calibrated too, although against my old integrale (which I gps'ed and was accurate) it measures about the same distance on a known journey, so I think it's close(ish).

What bhp were you pushing on that run, I'd guestimate it's in excess of 450bhp?

I'll have to do a faster run to get a better comparison...

Also factor in that I started at 60mph as well, so the lazy old single had to spool up to full boost too That's why it's a bit lethargic getting from 60 to 70 heh It'll do 10mph every 0.7s or so according to my analysis of the video. I shift early though as you spotted, and not too fast a shift at that.

Do a 60-120mph run to compare, I got that in 7.2s with two gearchanges

The car dyno'd at 580rwhp (626 at the fly) @ 1.4bar, that's 1.2bar so a bit less than that...

Singles are fun

-Ian

Here's my 1st run logged on the AP22. The rwhp isn't configured so ignore the value, though the graph of transmitted power should be accurate at least for comparison purposes. Though I am shifting well short of peak power this shows the effect of a slipping clutch!

Is anyone else able to provide logged 0-100+ runs from their Accelerometers, I'd be interested in keeping a record of these for comparison purposes.

Also factor in that I started at 60mph as well, so the lazy old single had to spool up to full boost too That's why it's a bit lethargic getting from 60 to 70 heh It'll do 10mph every 0.7s or so according to my analysis of the video. I shift early though as you spotted, and not too fast a shift at that.

 

Do a 60-120mph run to compare, I got that in 7.2s with two gearchanges

 

The car dyno'd at 580rwhp (626 at the fly) @ 1.4bar, that's 1.2bar so a bit less than that...

 

Singles are fun

 

-Ian

Yes I noticed that there was a bit of lag before the turbos spooled to full boost, as you say, which cost a bit of time at the start.

So with 0.7s per 10mph, 60-90 should take around 2.1 seconds then, assuming fairly linear acceleration over that small speed change - pretty impressive!

60-120 in 7.2s is also very impressive!

I'll try and do a 60-120 run then, so that could be done in just 3rd and 4th requiring just 1 change, rather than 2?

I'll be no where near as quick as your car, but I'm interested in the comparisons - if nothing else it entices me with the idea of a turbo upgrade

We need more video and graphs!

I'd really like to see how a BPU car should be performing, so I can compare against that. I'd like to have the performance of your car Ian (who wouldn't) but for the moment it's a bit like comparing chalk and cheese - hopefully I'll get there one day though

Next time I'm in mine with the accelerometer I'll try a 60-120

I doubt that it will be anywhere near 7.2secs though.

I notice `Dave-H` over stateside pulls 80-130mph in 3secs. exactly in his turboed N/A!

I'll try and do a 60-120 run then, so that could be done in just 3rd and 4th requiring just 1 change, rather than 2?

 

We need more video and graphs!

 

I'd really like to see how a BPU car should be performing, so I can compare against that. I'd like to have the performance of your car Ian (who wouldn't) but for the moment it's a bit like comparing chalk and cheese - hopefully I'll get there one day though

I don't think you can get to 120mph in 4th with a j-spec diff, V160 gearbox, and a stock rev limit, I think it's more like 115mph, so that looooong change from 4th to 5th is required

I know it was chalk and cheese but I figured you'd like the vid There probably aren't that many readily available vids like that either so that one is better than none I guess.

I agree we need more videos and graphs. I'll have to get some more done

-Ian

Yeah we need more video!!!

I did like the video a lot Ian It's like dangling the proverbial carrot (in this case a big single turbo) in front of me...

That change from 4th to 5th is probably the hardest to get right I find at high speed, shame it won't make it to 120mph in 4th then.

I'm only at circa 0.9 bar at the moment, need a bit of adjusting to get to 1.2 at which time I will take some more footage and get some real comparison figures from going from nearly stock to BPU

TBH thinking about it, I'm sure I've made 120mph in 4th, but then again I don't seem to have a rev limiter lol, not that I've found anway at 6800rpm, hmm maybe somethings been adjustivised in Japan before it came over.

I did a run a while ago it is an "indicated" 80 - 140 leptons

Its here

Looks like your car isn't hanging around either colsoop!

Ian C.

Just watched your video.

You naughty boy!

Ian C.

 

Just watched your video.

 

You naughty boy!

 

And there is me accidently not filming anything outside of the car so no-one can arrest me for being on a public road. Which of course, I wasn't. I was in my garage all along

And there is me accidently not filming anything outside of the car so no-one can arrest me for being on a public road. Which of course, I wasn't. I was in my garage all along

That accelaration looks awesome Ian

That's a very loooonnnng garage you got there

lol yes an extremely long garage! You didn't have your car up on blocks did ya I think I too could manage a 3 sec 80 - 130 like that

Good point though, best not to get footage of the road and your speed together (unless you really are on a private road of course) - otherwise you're gonna be "banged to rights" if they got hold of it!