Robbie C's Ibiza Cupra

[ian_cupra]

its always nice to have to pub talk figures but its how its put onto the road in real terms. Like mines only 249 horses, which you and i both know, it feels like much more

Cool, i doubt i'll have mine on the road by then but i'm aiming to get it sorted soon, be good if i could make it in time though

 

[Robbie C]

Yeah that's exactly it, and it never fails to make me smile Definitely mate.

That's cool - you're welcome to take mine out for a lap or two so you can feel for yourself how it compares

 

[ian_cupra]

oooo now that would be nice

i need to get my @rse into gear and get some bits bought for it!

 

[Robbie C]

Less talky more spendy!

 

[ian_cupra]

i know, i got no money to spendy right now

 

[PhilW]

Thats a massive difference. Weird.

Why did craig only rev to 6400 last time? Would the coast down make any difference revving to different points? Ambients and tyre(s) pressures might add to it as well.

Bet it feels quick but the torque drop of is rather large tho.

 

[Robbie C]

Yeah - I was a little taken aback I must admit. I didn't necessarily expect the same figures, but not such a massive deviation either. Ambience will make some difference I agree, but doesn't explain the difference in RPM scaling. Tyre pressures were checked on both days; 34 PSI all round.

Nice pick-up on the RPM shut-off Phil, it seems bear relevance here...

I've just had an email from Bill who's been trying to figure this out and looking over the reports he seems to think the car may have originally been run in 5th gear with the dyno calibrated for 4th, affecting the load on the rollers and skewing the RPM scaling; which is calibrated as an offset against 3,000 RPM.

Craig made some comments about my car being very lively and wanting to jump off the rollers, with only a limited number of strapping points installed when the car went on in January, so it's possible the car _may_ have been run in 5th to calm the delivery of power. If that were the case then it would elucidate a correlation between these power curves.

I can't personally remember where exactly the car was strapped down (I *think* it was at the sides and on the front) but it was still pretty lively and looking back over the printouts and noticing the fact that the power run was backed off at what "appears" to be 6400 RPM it would make logical sense, i.e. the RPM ratio between 4th and 5th matches the deviation between the curves. If that is correct, then the 6400 RPM seen on the graph is in fact more likely ~7,400 - shifting the numbers significantly.

With everything else remaining constant between both sets of power runs (most notably boost) then there's no way you'd see the power delivery shifted in such a way in real terms.

 

[Robbie C]

Bet it feels quick but the torque drop of is rather large tho.

Yeah it's been mapped to intentionally give a nice burst of torque after every gear change that eases off towards the redline where the little K03/4 can't sustain such flow. It's an aggressive little thing, though will always lack that top-end grunt

It's the car's eagerness to "get up and go" from so low down in the rev range that keeps me smiling

 

[ian_cupra]

you need to get out on a 1/4 mile run

 

[George 3G]

The 1/4 mile is the real rolling road. There is a formula that uses your average trap speed, and the weight of the car with the driver and it works out your bhp, it's been proven quite accurate!

 

[ibizacupra]

1/4 mile times wont account for the massive variablity of traction tho

yo gotta luv dyno lottery.
the figures i am seeing on std cars make me pretty confident this dyno is reading pretty much spot on.
what its showing is there is a large variance between rollers.. and setups etc

the figures are'nt the best for the pub, but are realistic i think.

 

[ibizacupra]

Thats a massive difference. Weird.

Why did craig only rev to 6400 last time? Would the coast down make any difference revving to different points? Ambients and tyre(s) pressures might add to it as well.

Bet it feels quick but the torque drop of is rather large tho.

Phil

there is a difference in the original dyno run from the report run, as it reported 5th gear as test gear, but also reported the final drive ratio, which was for 4th. Given there were traction issues, and the over wishbone strapping points were'nt there back in feb, the climbing up the front roller would likely have been occuring. Craig added more strapping points for my visit with my ibiza in May, so I dont think the over wishbone method could have been employed in feb by this token. It works, and was good advise by craig to employ this method, as we used it on robbies car on sunday and on dales corsa turbo, and wheelspin was'nt an issue once warmed up. choosing 5th would have helped tame the power delivery, but its a different load, and if the rpm scaler was different from the 4th/5th change then this would skew the rpm/torque readings.
I know when I change the ramp rate for a slower ramp rate, the plots all shift to the left, not to the extent of the difference between Febs plot and sundays tho.

hope this explains
bill

 

[PhilW]

Thanks for that bill, i just read the reply you gave rob about it. All makes sense doesnt it.

You must be happy with the way its going tho?

Shame i didnt have my car in previous form as its probably been on that dyno more than any other car. lol.

 

[Robbie C]

Thanks Bill.. appreciate the input.

I'm more than happy with the car itself Phil as the way in which it delivers the power on the road and compares against other higher powered cars will always be more important to me than out-and-out figures. Everybody loves an underdog!

As Bill has seen logging a number of standard cars now the dyno itself seems to be right on the money so it will be interesting to compare against other hybrids and K04s over time

 

[ibizacupra]

Thanks for that bill, i just read the reply you gave rob about it. All makes sense doesnt it.

You must be happy with the way its going tho?

Shame i didnt have my car in previous form as its probably been on that dyno more than any other car. lol.

I think the rollers must have your tyre treads worn into them

I am happy with the dynos accuracy. Its having the odd hissy fit on occasion like most computer based things do.. I have a call into Dastek currently (unanswered still!) regarding the logger, as wideband seems to have died.. I thought it was the innovate lc-1, so bought a new one, but it still refuses to work properly. I am using my AEM Wideband currently, but cant log it on the dyno's software which is a pain.
Strapping techniques seem very key to keeping traction and warm up methods, and some very good advise and tips off Craig. Working well. std cars are on the money, remapped ones to me seem also to be what "I personally expect", however, as we all know, claimed figures from most manufacturers of software etc, all claim the best dyno figures they can, even if those figures are on happier dyno's.

I quickly ran up a PD130 golf4 yesterday, and 140bhp/240lbft from bog stock car

 

[MarkWales]

gutted to see the difference in runs there wonder what mine actally is now

 

[M1KEH]

It's only a number, you still enjoy your car yeah?

 

[Robbie C]

It's only a number, you still enjoy your car yeah?

Me? I've no complaints at all - as per above it's how it drives on the road/track and compares against other cars that interests me far more than numbers.

I can't say that I wasn't a little despondent at first, but who wouldn't be when compared to my previous run.

Let's also not forget ambient temps of 31 Deg C compared to 8 in January - a massive difference that can't be ignored. Numbers are nice for bragging rights but far too many people become too hung up on them and lose sight.

The real annoyance comes from trying to explain "dyno lottery" and the aspect of power delivery vs pure figures to those ignorant of these actualities, but I shan't lose any sleep over it

 

[M1KEH]

Was mark it was aimed at really, saying he was gutted.

 

[Robbie C]

I wouldn't necessarily assume that Mark's or anyone else's figure is inaccurate. If my car was run in 5th vs a calibration for 4th there's nothing to say this was repeated for other cars.