Hoppy

Wise words from Andy as usual

Lots of chest-beating stuff here (nuffin wrong with that ) but only Andy F and Adam M have really touched on the major problem with this sort of power on the road - turbo lag.

Quick superbikes are the closest most people ever get to this kind of performance - including me - and they are easy to ride because they are normally aspirated and have a pretty much straight-line power curve. The power delivery is smooth and progressive. You get what you want, when you want it.

Now check the power graphs for a 600bhp Scoob, or even a 500bhp one. It's shaped like a snake, with a massive power hike that comes in very hard, very suddenly and always a considerable sometime after you've pressed the pedal. That's what makes a huge-power Scooby hard to drive, scary and dangerous.

Good luck with the project though

Richard.

PS Edited to add, what about brakes? My car has some fab AP brakes and can stop time and again from 100mph in under 3.5 secs (3.2 secs on grippy surface ). Nobody ever says that their brakes are too powerful, even though that is is a phenominal rate of decelleration for a road car. And that's because the braking is controllable - smooth and progressive. Well, if you can call 1.4g 'smooth'

martyp1

I will let you know mark when i get it all finished,Tell me when and where you are going up the hill i will come over and have a look.
I got the bug for taking the car up the drag from watching Andy F,thought i would have to give it a go even if the driver behind the wheel needs a lot of practice
martin

Oldfella

iTrader: (3)

Lol, my second time ever on the strip, I staged next to Andy, he has some very nice rear lights

stevebt

iTrader: (8)

who won

Oldfella

iTrader: (3)

Andy, only just, I would estimate that he was less than 1/4 in front

ZEN Performance

Shame you haven't tried the 35 on a reasonably sized track. I found mine would be spooling like mad on partial throttle (you could hear it), and as soon as you put your foot down off a bend the power came in with no lag. It's a bit different if you're coming in to a harpin and want to get back on the throttle sharpish, but the vanilla 35R wasn't too bad at all on a 2.5 engine.

Paul

Trout

iTrader: (1)

Have you driven a well sorted 550bhp Scooby?

Mine had a diddy turbo (was it a 30R Andy? Not AFAIK) and it produced boost from 2,700rpm and massive torque from around 3,000rpm - both the boost threshold and boost lag were remarkably good for such 'big' turbo.

And it could have been made even more driveable utilising a smaller exhaust housing with a small sacrifice to top end.

Also as I mentioned earlier for my "low 500's" 555bhp the T6 was used to manage the boost profile so the car did not go too nuts low down. Originally it produced over 500 lbs of torque at 3,000rpm which we felt was too much, too suddenly low down.

Of course maybe that is not possible with 600bhp as Andy so keenly points out.

Rannoch

Andy.F

Correct I don't believe that sort of torque at 3000 rpm is possible on a 600bhp capable turbo when fitted to a Subaru 2.3 or 2.5
Profiling the boost rise against throttle/rpm is easy, the OEM JECS and Denso ECUs do this as standard, no need to spend ££££'s on a T6 The thing that no ECU can do is bring the boost in any quicker than the turbo can spool up, its like being connected to the throttle via a long elastic band

I agree Paul that on track with a fully heated exhaust and cooled induction things improve a bit with regard to spool but the lower gear response is still not good enough for making a quick road car.

Andy

Trout

iTrader: (1)

You have a MAF that can flow that much air!!

Andy.F

Yes ! Although at that bhp level I would be using my maf conversion which allows any maf based ECU to run from a map sensor (as i do on my own maf based PFC)

flat4

i drove Mikee's car around Donington last year, could of done with a bit more power TBH

Aztec Performance Ltd

iTrader: (234)

or with a another gear or two and no running oil slick trying to catch you out

flat4

that too!

wrc350bhp

assume this 600bhp is still rcms trademark a 2.0?

David_Wallis

As ive said before I wouldnt ever consider using a 4 cylinder subaru at 600hp as a road car. I dont care who builds it, its just not sensible.

Anybody that tells you they've done miles and miles with over 500hp is either lying or just not driving the car on boost.. My idea of driving a car is using the rev range and power band, anything else is classed as 'cruising'

Also I dont think its practical to do on road fuel, or should I say std pump fuel which is what I would want from a road car.

I make no illusions, my car is not practical for the road! And it wasnt built to be, nor is it (or has it!) been competitive at drag racing yet, and wont be next year, when ill potentially push it to around 650 ish bhp

some video's I posted ages ago whilst testing on the road can be found here http://bbs.scoobynet.co.uk/showthread.php?t=452865

There is a missfire at the top end, now fixed by running a home made custom optical crank sensor. Theres also a problem with 3rd gear not wanting to be selected, This has now been resolved by removing the 6spd.

One point is last time out I borrowed a 5spd box, and gently launched the car and snapped the end of a rear driveshaft in the rain.

Expect breakages, and expect to get disheartend when youve traveled to a dragday to try the car only to break it.. And they arent drag days / rwyb days when your at that level as it becomes a weekend / maybe a weeks prep prior.

Also it helps to have an idea what is going on under the bonnet at that level.
Ie a little more than a knocklink is advised

David

alanjack

Must be how Schumi feels What a buzz that must be.

*AL*

So what's this car like................it must be done by now as this is an old post?