Power to weight calculator accuracy

[Aly]

Right I've been quite bored tonight.
I love using Excel, any excuse to have a play haha :D

I've been using this:
http://www.letstorquebhp.com/calculator.asp

To calculate various 1/4 miles times from some cars.
I used Parkers as a source for power and weight (OK not the best source to use)

Here is what I come up with.

http://i119.photobucket.com/albums/o136/aly05189/miles.png

Just want opinions if this seems right with cars I've used. Also I think my car is a bit lighter than what I've put it down as but I didn't want to be too ambitious.
Also for the RWD cars I chose RWD.

Please don't turn this thread into an argument.

[Kyza]

Seems slightly too optimistic for your saxo. Maybe late 14's. Another factor which isnt taken into account with this is the gearing. The Civic EP3 has 6 gears and therefore would waste time with say an extra gearchange over the VTS and also aerodynamics of the cars and rotational mass or larger wheels and tyres or larger brake discs.

[Aly]

Seems slightly too optimistic for your saxo. Maybe late 14's.

That's what I was thinking :S don't want arguments just opinions lol, any cars there people have owned, I thought mine seemed a bit low :S

[DannyVTS]

Where did you get your figures lol and how is your VTS 170kg lighter than a standard VTS :| Standard VTS is 920 before airbagged seats and 935kg with airbagged seats IIRC

BHP/tonne woulda been nice too ;P

[Aly]

Where did you get your figures lol and how is your VTS 170kg lighter than a standard VTS :| Standard VTS is 920 before airbagged seats and 935kg with airbagged seats IIRC

BHP/tonne woulda been nice too ;P

Was a guess I've seen one's weighed on here and SSC with similar stripping and they come up 780-820kg so somewhere in that region.

[DannyVTS]

Whats been stripped off it like? My first VTS was a bare shell with seats and an engine but I doubt it was over 100kg's lighter than the current!

[DannyVTS]

BTW, there was a car IDENTICAL to yours at Ikea Birkstall on Sunday night!

[Aly]

BTW, there was a car IDENTICAL to yours at Ikea Birkstall on Sunday night!

That's its brother, there were 2 identical one's built.

[Barry123]

Aly. I've got a calculator I made in excel which factors, aero, drag, power throughout the rev range, gear ratio's, shift times etc etc.

A few people have asked me to release it but to be honest, and not being rude, I don't think most people would understand it (since its seriously user unfriendly).

All you need is a rolling road print out - you then enter the power outputs at various revs into a particular sheet and away you go.

It was in beta, as I took the simulation of acceleration from 0rpm in 1st which isn't possible but the 0-60, 0-100 1/4 mile times are all fairly reliable.
You're more than welcome to have me send it over so you can plug in your own details and see what it comes out as.

ads

[DannyVTS]

That's its brother, there were 2 identical one's built.

Do you know the owner?

[dougieph2]

aye your waaaaaaaaayyy off with a few of them aly

[Aly]

Aly. I've got a calculator I made in excel which factors, aero, drag, power throughout the rev range, gear ratio's, shift times etc etc.

A few people have asked me to release it but to be honest, and not being rude, I don't think most people would understand it (since its seriously user unfriendly).

All you need is a rolling road print out - you then enter the power outputs at various revs into a particular sheet and away you go.

It was in beta, as I took the simulation of acceleration from 0rpm in 1st which isn't possible but the 0-60, 0-100 1/4 mile times are all fairly reliable.
You're more than welcome to have me send it over so you can plug in your own details and see what it comes out as.

ads

And we aren't best mates because........ :homme:

Do you know the owner?

I don't sorry that cars been sold on a few times now lol

aye your waaaaaaaaayyy off with a few of them aly

Suck my fat one dougie :A: haha

[DannyVTS]

Good, there was some proper skanky lardy girls near it other neet..

[Kyza]

830kgs is a good estimate. Mine VTR weighed that with full interior removed, spare wheel cage etc dash remaining and sound deadening behind the dash. VTS would obviously weigh slightly more because of the heavier engine.

[Kyza]

Aly. I've got a calculator I made in excel which factors, aero, drag, power throughout the rev range, gear ratio's, shift times etc etc.

A few people have asked me to release it but to be honest, and not being rude, I don't think most people would understand it (since its seriously user unfriendly).

All you need is a rolling road print out - you then enter the power outputs at various revs into a particular sheet and away you go.

It was in beta, as I took the simulation of acceleration from 0rpm in 1st which isn't possible but the 0-60, 0-100 1/4 mile times are all fairly reliable.
You're more than welcome to have me send it over so you can plug in your own details and see what it comes out as.

ads

Much more accurate, would be interesting to see.

[dannygti]

800kgs is VERY good going. my car weighed 790kgs and i have done a lot of work, mostly bits you cant see.

seems about right to me, maybe low 14's is a little more doable.

[Aly]

800kgs is VERY good going. my car weighed 790kgs and i have done a lot of work, mostly bits you cant see.

seems about right to me, maybe low 14's is a little more doable.

Cheers Danny, I might get it weighed I am interested.

[DannyVTS]

you'll be disappointed lol, book figures are dry weights

[JRC1]

Would have been good to see the bhp/tonne figs in a 4th column :p Interesting though, i've used that website loads of times and always wondered how accurate it actually is. Think I might have a play around with some figures now lol

[Aly]

Would have been good to see the bhp/tonne figs in a 4th column :p Interesting though, i've used that website loads of times and always wondered how accurate it actually is. Think I might have a play around with some figures now lol

I can pm you the file if you wanna add them yourself, saves you putting them all in

EDIT: Here is the file if you want to download it
http://www.megaupload.com/?d=4TDSZIBO

[Barry123]

And we aren't best mates because........ :homme:

Much more accurate, would be interesting to see.

It's probably easier if you send over your email addresses I just uploaded to an ftp site or something (I don't really understand it).

as said, it's beta, so it needs some refining to be truly usable - but you guys might be able to point out certain problems I haven't thought about. Oh it has a Macro, but this is a linear-interpolation algorithm, not some nasty bug or something.

its up to you guys.

ads

[Kyza]

Id have to find the CD that has Excel on first and install that before wasting your time sending it over! Thanks, will contact you once and if I find the CD!

[Barry123]

http://www.megaupload.com/?d=SRGLCP06

feedback/insults welcome.

[Aly]

Ads your talents are wasted you're a genious, I'm reading through it all now.
Well Done! :D

[Barry123]

Ads your talents are wasted you're a genious, I'm reading through it all now.
Well Done! :D

Have a play around with it and if there's anything you don't understand then give me a shout.

I've got to apologise for it really,. It started out as a record for my trips and fuel consumption. Then started off with something similar to how you started with your excel sheet and then just built it up from there - hence the mess!

[Aly]

Have a play around with it and if there's anything you don't understand then give me a shout.

I've got to apologise for it really,. It started out as a record for my trips and fuel consumption. Then started off with something similar to how you started with your excel sheet and then just built it up from there - hence the mess!

I suppose it's better doing that than being a drug addict or something else along them lines...

[JRC1]

http://www.megaupload.com/?d=SRGLCP06

feedback/insults welcome.

I see myself as a bit of an Excel pro, but i've gotta say, that spreadsheet is hugely impressive! Transmission Selector tab is proper handy as well.. Good to know the input/output shaft teeth for the gearboxes, know for double definite that mines an S1 box now lol (not that I had any doubts!)

Great work though, thanks :y:

[Barry123]

I suppose it's better doing that than being a drug addict or something else along them lines...

Sorry Aly, I realised I've hijacked the thread a bit :wacko:

I see myself as a bit of an Excel pro, but i've gotta say, that spreadsheet is hugely impressive! Transmission Selector tab is proper handy as well.. Good to know the input/output shaft teeth for the gearboxes, know for double definite that mines an S1 box now lol (not that I had any doubts!)

Great work though, thanks :y:

Yeah the transmission selector is nice a neat, more user friendly - that was the last thing I edited lol. i'm no pro with excel - the rest is really just based on calculations, actual use of excel's functions is actually pretty limited so the plan is to start to simplify and make the rest more user friendly.

At the moment it's a bit of a problem for anyone who doesn't have a standard revving VTS for calculating the acceleration rates. They have to rewrite the shift/rev points in the Acceleration Rate sheet - So the next stage is to do it so it automates the shift points based on the last input of engine data (i.e. the last rev point)... if that makes sense. lol

[adam111]

It's probably not that accurate, but i got a result in the low 15's on that website.

[ClumpyVtR]

IIRC isnt the ibiza cupra 150bhp? :)

[jonathon5]

Your Saxo figure is way out

So is your focus St figure,

Clio 172 cup was 14.9 as STD as tested by renaultsport & evo

Saxo Vts 970kg ????