john banks

Pavlo, you need not have bothered with a 2.5 litre engine and GT30R, you could have run a VF34 on a 2.0 and had 75% of the power Now sit the turbos next to each other for me and try not to laugh too much...

RR

At the end of the day John if it weighs 10% more it needs more power to compensate for this and it has to have extra trans loss "Fact". So theres 380bhp and the extra trans loss to take into account. But to be honest the amount of Local scoobs who are claiming 350-450bhp and get nowhere near my car in terms in performance is unreal. I have not come across one that gets close "Fact". I cant see a vf34 making 380bhp @ 1.2bar. But i dont know much about scooby tuning.

Bottom line is nice results Bighead, enjoy the car. If your happy nothing else really matters.

Ninnybobs

RR,

You make it sound as if there are a lot of 350-450bhp scoobs around near us. I can't think of that many!!!!

Martin

Pavlo

So let me get this straight. Your car weights 1107kg according to the various figures you have given. It has 343hp @ flywheel, and 306hp @ wheels.

You can expect the losses when running on a set of rollers to be somewhat higher than those actually seen when running on a flat road. So your probably experiencing a little more than 306hp at the wheels. This works both ways, and the average scoob is looking at just 50hp losses at about 120mph (in fact these are the losses reported on Bighead's graph)

Classic scoob can easily weight about 1250kg, then of course there is the driver, say 80kg, and 20kg of fuel, say 1350kg - 1400kg on the road depending on the model. Assuming 1400kg just to be safe, 380hp at the flywheel, and 330hp at the wheels, makes 236hp/ton at the wheels.

If we add the same 100kg for driver and fuel to a Seat Ibiza, and take say 310hp at the wheels we get 256hp/ton.

So obviously slight advantage to the Seat with thos numbers. However, when we take the lighter weight Classic at 1350kg, we get 244hp/ton.

That in my opinion is pretty close, so I don't see the scoob needing more than 400hp to equal your Seat, let alone a 460.

Combine this with the immensly wide power band, and better traction, I can only agree that any scoobs near you claiming 450hp at the flywheel are obviously deluded.

Paul

john banks

If you have a passenger, fuel and fluids, difference is more like 8% in weight. The extra transmission loss is small, and IMHO more than made up for from the gain in traction. A car with 8% more power and 8% more weight will be quicker all other things being equal. Power at wheels to weight ratio is not a good marker for acceleration, try (power at wheels-drag):weight.

Besides, I've given you real figures (not calculations that ignore most of the variables) from the 430-440 BHP Scooby that you say would be required to match an IHI Ibiza, yet the acceleration figures seem to blow the example Stage III IHI Ibiza figures into the weeds at any speed?

Care to revise your Scooby power downwards that you can thrash ? I know a 340 BHP Scooby that would sort those figures

Pavlo

Of course, as powe levels increase, you have to look more closely at the aerodrag of cars. 2 cars with equal power to weights will not be equal at high speed in terms of acceleration if they share the same drag. The car with more power, will be quicker.

Paul

StickyMicky

is RR the bloke who was pestering the lancer evo baord as well?

Tone Loc

iTrader: (1)

At the chance of sounding stupid...... which Ibiza (year) are we talking about here. I presume this is an earlier version as the current versions sport a kerb weight of 1240kg????

Tony.

Tone Loc

iTrader: (1)

Just checked Seats web site, i was wrong. They have the 1.8 20V listed as 1248kg .

Tony.

P.s... these things are ugly as foooooook

RR

There are plenty of scooby owners who dont come on SC and who are not members of TTS and are claiming 350+bhp.

You guys are unreal i accepted and said many posts ago the actual calculations i based my figures on are flawed. As yours are as well its 1119kgs kerb weight. My point when coming on this thread was to see how a vf34 made 380bhp and it would be good for me to know. I thought it never had the airflow to make such power, but i am always willing to take a look and see if theres been anything i can benefit from or i may of missed. The better educated i am on the facts the better the choice i can make in the future.

john banks

People will claim all sorts of things for power, few will produce acceleration results that corroborate them IHI Ibizas seem the same? But I know there aren't many because of the waiting lists.

Midlife......

iTrader: (2)

RR

"plenty of Scooby owners with 350 BHP +" ............. I'm not one as I'm currently on 325 BHP

Not sure who else is in the area you are thinking off ??

Midlife.....

RR

You doubt my figures John. And you dont think the accelaration results corrborate them. Very intresting i will ask my tuner to explain why this is the case.

bighead

iTrader: (1)

Thanks..RR .. it does not matter what bhp my car is putting out
it only matters if I don't enjoy it
High bhp is for guys in the pub

ps...do not mean to offend anyone , these are just my thoughts >

RR is right ...the more info you have the better the choice regarding mods .....that is what these forum are for is it not

Andy.F

I think the problem here is that every std scoob owner with a dump valve "estimates" he has 330-350 bhp
RR has probably never actually lined up alongside a genuine 350bhp scoob.

Andy

dowser

Andy.F making reconcilliatory posts *really* freaks me out........

I'd like to see the boost profile for the 380 hp vf34 - I'd never have thought it was possible, but then Euro engines fell apart at anything much over 300 hp a few years ago so who knows. Maybe per cylinder timing trim from the Motec?

Richard

john banks

RR, I was referring to the Scoobies. But I am beginning to wonder if the Ibizas were the same, as the acceleration times I posted (no one has mentioned any better, and weren't they even a tuner special?) seem a bit crap in gear for the power to weight claimed for a stage III IHI. Maybe as I said they spin it away until there isn't enough power to really move it at high speed? Or maybe your figures are better? If you are so keen to beat rally replicas and give kill stories, perhaps some black dyno figures to back up your claims would be good.

You set the cat amongst the pigeons when you suggested 460 BHP would be required in a Classic Scooby, when I know I was beating (in fact making mincemeat of) those in gear times with a claimed 100 BHP less but with big torque (1.7 bar TD05) which I could transfer to the road. Andy F will remember the Evo on the same rollers on the same day that had c.440 BHP which was consistently accelerated away from under power at Fife Airport with different drivers in each. It is not all about power to weight, or about daft dyno claims.

john banks

Here we are.... Scooby with "304" BHP (that's what the rollers said ), acceleration times in 4th gear as follows (max speed in gear 96 mph, I have a 2.3 second 60-80 mph when the car had slightly different gearing), both with a passenger and full tank of fuel:

60-80mph 2.4 (Ibiza 2.8)
70-90mph 2.7 (Ibiza 3.1)

Previous data off mine in "356" BHP spec:

80-100 3.2 (Ibiza 2.9)
90-110 3.4 (Ibiza 4.0)

Now do you understand my hilarity at the power figures required? Especially as my present setup which doesn't have anywhere near 460 BHP does 70-90 in 2.0 vs 3.1 seconds?

Bring on your data, let's see it

AndrewC

This looks very similar to my plot from ProSport at the begininng of October, my spec is similar to yours except that I have a f/e TD05 and a ****ty old 6 row Link. I made 383bhp @ and 369ftlb @ 1.4bar. 311 @ wheels. Pete suggested that perhaps Mick Kehl should take a look at my map

Can I just ask what the Temp figure is on your graph?

Andrew...

Pavlo

29 degrees is what I see with some image manipulation (tilt laptop screen!)
correction is 1.060

SiHethers

Can I join in?

My own classic (without aircon) MY99 with vf34 is timed as follows:

2nd 30-50 1.6s
40-60 1.5s

3rd 60-80 2.2s
70-90 2.4s

This is with estimated kerb weight of 1350kg 20psi boost and 270bhp at the wheels.

In a straight-line an ibiza with the figures quoted by JB would be in my RVM

Simon

Edited as per JBs comment below, doh

bighead

iTrader: (1)

Andrew... the temp on the graph is not 29 degrees...but 129 F

john banks

270 BHP/ton ATW with 1350kg would be 365 ATW though Simon. I think you mean 270 WHP estimated on your weight of 1350 kg?

Interesting that the Jabbasport IHI figures seem a bit higher on Jabba's than G-Force's rollers??

With the acceleration figures quoted, which were from the same poster, perhaps 255 WHP is more like it which is why the Scoobies of modest power are trouncing them? Maybe you should ask Jabba a few questions RR?

Andy.F

Was that the EGT ?

bighead

iTrader: (1)

Andy !

RR

My car made 306bhp @ the wheels @ Jabba. 343bhp flywheel. At Jbs autodesigns 325bhp (flywheel) 293 @ the wheels. 2 diff dynos 2 diff days 2 diff operators. At Jbs it was the 4-5th run as on the previous runs the car kept spinning on the rollers. But i am open to suggestion that the figures could be wrong. And i would like an answer one way or another myself, and with this in mind i will happily put the car on Power Engineerings rollers in the next couple of months as it already was as part of a group RR day in Feb. It seems like the only way of finding out exactly what is going on and why its not performing on roads (as u have suggested / in gear times) as well as its scooby counter parts. Either way good or Bad i will let u know what it makes at Power Engineering. I will let Power Engineerings Rollers decide the outcome either way. Cheers.

john banks

PE can be generous as well, just look at the dyno site and the spec of cars and figures they achieve... I hit the same there with TD04 hybrid that I needed an MD304 to hit at Star, the car being obviously quicker on the latter spec. Figures at PE can show standard cars running more than decently modified cars on other rollers.

Try Powerstation for down to earth figures, of course depending on location?

RR

Will do John, all i want is a true reflection good/bad. A trip to Powerstation it is.

Pavlo

Powerstation is screwed, or at least it was, they had a flood and it affected the rollers in some way. Depending on whre you are, there is also G-Force motorsport in Aylesbury (Dyno Dynamics rollers), and www.surreyrollingroad.co.uk to, in surrey of course! They are springing up all over the place.

Paul

RR

Whats the feeling on Well Lane.