RE: 800bhp Celica Is Fastest Car At Goodwood

[anonymous-user]

chuntington101 said:

Max_Torque said:

I call Bull too!

700bhp @5700rpm would require a BMEP of 54.9 bar (for a 2.0 engine) and a BSAC of approx 2.3kg/kwhr, either figure is bit like saying, "yeah mate, my 1.3l corsa can go 200 mph".......


are you sure it's not 7500rpm??? (even that would be going some, but just possible)

Max, are you saying that 700bhp at 7.5k rpm on a 2.0ltr is hard to achieve? I know your a very samrt bloke so im not going to jump in feet firsts and ask why, but why? lol

Chris.

well "power" is "torque x speed" so, the faster you rev (the speed bit) the less torque you need to make that power. (hence F1 engines only make just over 100Nm/litre (being n/a) but make 700bhp because they make that torque at very high rpm. So to make 700bhp from a 2.0 litre engine requires more torque at 5700rpm than it does to make that same 700bhp at 7500rpm. In fact, it requires a "Brake Mean Effective Pressure" of 55bar! (BMEP is sort of like "average torque", it is the mean pressure you would have to push down on the piston with over the entire power stroke to make that much power (at that speed).

Now, 55bar is unheard of, basically no piston/ bore/crank etc can withstand that sort of loading. Typical "high boost" engines can push into the mid 30's (with limited durability of course) and "road cars" tend to sit in the low 20's if turbo'd.

I suspect that the author of that piece had a bit of finger trouble and got their 5 and 7 the wrong way around ;-)

(Vixpy1, i replied to you a could of days ago (your email got initally sent to my spam folder, so you might want to check yours ;-) (I think my email checker automatically marks anything from PH as "spam" (probably sensibly....... ;-)

[Pingman]

Lordbenny said:

The two runs

http://www.youtube.com/watch?v=96QbYt_Pj9w

Holy crap that's quick

[Vixpy1]

Max_Torque said:

well "power" is "torque x speed" so, the faster you rev (the speed bit) the less torque you need to make that power. (hence F1 engines only make just over 100Nm/litre (being n/a) but make 700bhp because they make that torque at very high rpm. So to make 700bhp from a 2.0 litre engine requires more torque at 5700rpm than it does to make that same 700bhp at 7500rpm. In fact, it requires a "Brake Mean Effective Pressure" of 55bar! (BMEP is sort of like "average torque", it is the mean pressure you would have to push down on the piston with over the entire power stroke to make that much power (at that speed).

Now, 55bar is unheard of, basically no piston/ bore/crank etc can withstand that sort of loading. Typical "high boost" engines can push into the mid 30's (with limited durability of course) and "road cars" tend to sit in the low 20's if turbo'd.

I suspect that the author of that piece had a bit of finger trouble and got their 5 and 7 the wrong way around ;-)

(Vixpy1, i replied to you a could of days ago (your email got initally sent to my spam folder, so you might want to check yours ;-) (I think my email checker automatically marks anything from PH as "spam" (probably sensibly....... ;-)

off to check my spam folder then

[Silent1]

I suspect 7,500 too as 5,700 would make the torque/power curves look like a diesel!

[grippa]

FOS Turning into Macdonalds drive thou

[Mrbarry]

Adrians GT4X (Loosely a generation 7 chassis with generation 6 engine and running gear) is heavier than this car and runs 9 second quarter mile sprints, and yes it does reach over 200mph on a 2 mile straight, you tube has video proof from an event held last year.

I think Jonnys car is a real feet of engineering, even if it is a bit 'orange' for my liking truth be told. It also has an MOT! But it isnt about how it looks its about performance. A pro rally driver in a tarmac spec rally car with a down force package, sounds like fun to me!

Edited by Mrbarry on Wednesday 6th July 11:32

[J90JAM]

clark223 said:

I think it was Heikki Kovalainen in 2006. I believe he was driving the 2005 Renault R25 F1 car, dont know the exact time, but it looked scarily fast....

Correct. The time was 39.8*. Though I couldn't find any videos of it I would've loved to be there in '06 to see that!

ultegra said:

The thing was he was the only driver competing. I don't think he had sussed out that the FOS isn't a 'serious' hill climb.

Milner has been attending Goodwood for years, he knows what it's all about but he is extremely competitive and likes tearing it up the hill, he usually finishes in the top 3 of the shootout each year too. Personally I love it when he lines up at the start, you can feel the anticipation in the crowd because everybody knows it's going to be a balls out run, he doesn't know any other way. At one point, when he almost lost it coming out of the first corner, he was headed for exactly where I was standing, which was a bit unnerving but he kept his foot in all the way (on the grass too!) and got it back on track. You've gotta love it.

[chuntington101]

Max_Torque said:

well "power" is "torque x speed" so, the faster you rev (the speed bit) the less torque you need to make that power. (hence F1 engines only make just over 100Nm/litre (being n/a) but make 700bhp because they make that torque at very high rpm. So to make 700bhp from a 2.0 litre engine requires more torque at 5700rpm than it does to make that same 700bhp at 7500rpm. In fact, it requires a "Brake Mean Effective Pressure" of 55bar! (BMEP is sort of like "average torque", it is the mean pressure you would have to push down on the piston with over the entire power stroke to make that much power (at that speed).

Now, 55bar is unheard of, basically no piston/ bore/crank etc can withstand that sort of loading. Typical "high boost" engines can push into the mid 30's (with limited durability of course) and "road cars" tend to sit in the low 20's if turbo'd.

I suspect that the author of that piece had a bit of finger trouble and got their 5 and 7 the wrong way around ;-)

(Vixpy1, i replied to you a could of days ago (your email got initally sent to my spam folder, so you might want to check yours ;-) (I think my email checker automatically marks anything from PH as "spam" (probably sensibly....... ;-)

See i knew you would have a good answer! lol

I do however have to ask about this figure being unheard of. THe EVO guys have pusghed well over 800lbsft of torque out of 2.3ltr engines and have made well over 1000bhp on 2.0ltrs. How do their BMEPs conmpare to 700bhp at 5700rpm?

Thanks again,

Chris.

[Juicetin1]

http://www.youtube.com/watch?v=U5Wg3JUcKwM

This is still my favourite FOS clip, Rod Millen Pikes Peak Tacoma, would have probably got into the 45's if he hadnt bogged the start.

[rev-erend]

Now that custom built cars are being entered for FOS - it's about time some of the hill climb boys are invited to participate to show how it's really done.

[chuntington101]

The Wookie said:

I was having a poke around it with the team in the assembly area, got chatting to some of their guys and apparently the thing drops two inches once up to speed from the downforce and ground effect it generates, which explained the 'bus door' brushes lining the sills and diffuser!

As it happened the driver was a bit unhappy about us lot peering about under the bonnet... One thing I would say is that the hoses and manifold looked like they were specced for considerably more than 1 bar of boost!

Perhaps with the supercharger it was compound charged rather than sequential, so 1 bar could only be the first stage?

Wookie, i would guess the are feeding the Rotex supercharger with boost from the turbo. Not really the best way to go about it (alot say positive displacement (PD) blowers are the best as you get boost as soon as you get on the throttle no matter what the RPM) but as the car will spend all of its time in the top half of the RPM band the little rotex will already be providing some boost by then. Also im guessing you wouldn't need to cool the intake air before it hits the supercharger like you would if a PD blower was used.

However seems like a lot of work to me if they alreeady planned on using N2O! you can set the N2O to help mask lag by injecting say a 100bhp shot that tails off as the boost rises back up to where it should be.

Still would love to0 see the engine bay.

Chris.

[SteveS Cup]

soad said:

Yes

Ah... It was probably my favourite car last year... looked superb going up the hill... not sure about the Orange!

[Mr Senna]

One of the many reasons why the F1 cars are not timed. See below

The accidents can be big and crowd is at a great risk I guess.

In 1994 I was 20 feet away from this;

http://www.youtube.com/watch?v=pRUd-Epu9iQ

It was a close call....

[joz8968]

Mr Senna said:

...In 1994 I was 20 feet away from this;

http://www.youtube.com/watch?v=pRUd-Epu9iQ

It was a close call....

Gumph!!!

[FourWheelDrift]

Juicetin1 said:

http://www.youtube.com/watch?v=U5Wg3JUcKwM

This is still my favourite FOS clip, Rod Millen Pikes Peak Tacoma, would have probably got into the 45's if he hadnt bogged the start.

That always impresses me too, hardly ever in control of the bucking bronco up a wet narrow tarmac road spray painting the hay bales oily black as he goes. And as the comment on the video says "imagine how close to the Range Rover he would have got if he hadn't stalled it!"

[anonymous-user]

chuntington101 said:

See i knew you would have a good answer! lol

I do however have to ask about this figure being unheard of. THe EVO guys have pusghed well over 800lbsft of torque out of 2.3ltr engines and have made well over 1000bhp on 2.0ltrs. How do their BMEPs conmpare to 700bhp at 5700rpm?

Thanks again,

Chris.

The simple answer of course, is that, er, there isn't one!

The first thing to question is the validity of those figures? Are they properly stabilised ISO corrected (and accurately calibrated) steady state engine dyno values? (or just rolling road data etc).

800lbsft is 1085Nm, which is 470Nm/litre or 59.1bar BMEP on a 2.3litre engine.

Now i have worked extensively on WRC engines, and the absolute best of those could do maybe 800Nm at a push (with things like a £10k turbo etc!).

Now, with nitrous, i could see 800lbsft being possible, but diffucult in reality, and for how long it would last, who knows ???


1000bhp from 2 litres is totally possible, but would require in the order or 11krpm to do realistically.

Many years ago now, i took a Prototype Focus RS (mk1) to the RS owners club track day at Donington race circuit. Where we proceeded to overtake cars that made "over 500bhp", and yet, i had run the engine in that RS on the dyno the week before, and know for a fact that it made exactly 231bhp........


My car makes somewhat over 600bhp from 2 litres (@7850rpm stabilised steady state engine dyno) and even that (36bar BMEP) actually cracked the block during the dyno running. Another car i calibrated (scooby turbo) made just over 430bhp on the engine dyno, but subsiquent validation work once installed in the car showed "over 550bhp" flash readings on a rolling road (and it was a decent, accurately cal'd rolling road, not the normal "send the customers away happy" calibrated one..... ;-)

In summary, how long is a piece of string???

[kaiowas]

chuntington101 said:

Wookie, i would guess the are feeding the Rotex supercharger with boost from the turbo. Not really the best way to go about it (alot say positive displacement (PD) blowers are the best as you get boost as soon as you get on the throttle no matter what the RPM) but as the car will spend all of its time in the top half of the RPM band the little rotex will already be providing some boost by then. Also im guessing you wouldn't need to cool the intake air before it hits the supercharger like you would if a PD blower was used.

However seems like a lot of work to me if they alreeady planned on using N2O! you can set the N2O to help mask lag by injecting say a 100bhp shot that tails off as the boost rises back up to where it should be.

Still would love to0 see the engine bay.

Chris.

Nitrous isn't allowed in TSS so that's only on there for Goodwood (same story with the slicks, plus the agressive aero isn't really practical at most of the venues we use so isn't normally on the car either). The SC was new for the last round too so it's a case of continuous development.

Car was still white last time I saw it too, I've heard mention that the orange is only a wrap so I'm not sure how permanent that is. Guess I'll find out in a couple of weeks when TSS goes to Barkston Heath

[anonymous-user]

Max_Torque said:

Now i have worked extensively on WRC engines, and the absolute best of those could do maybe 800Nm at a push (with things like a £10k turbo etc!).

Of course those run a very small turbo restrictor (34mm) so the turbo's used are rather unique and not a good reference point for these current unrestricted turbo engines being run in cars like these.

[anonymous-user]

johnfelstead said:

Max_Torque said:

Now i have worked extensively on WRC engines, and the absolute best of those could do maybe 800Nm at a push (with things like a £10k turbo etc!).

Of course those run a very small turbo restrictor (34mm) so the turbo's used are rather unique and not a good reference point for these current unrestricted turbo engines being run in cars like these.

except of course they are a perfect reffence point for the following reasons:

1) when you are "air restricted" maximum performance comes from maximum efficiency, be that burn rate, friction reduction, parasitic load reduction, optimum fuel preperation, maximum manifold volumetric efficiency (so you can move as much air with as little air as possible)etc etc
2) the 34mm restricted engines are not "torque" limited, just "power limited" (in fact, they are effectively constant power engines)
3) massive develpment of antilag systems (especially with the seperate combustor systems ;-) means you can run massive boost at low rpm (how does 3.5bar(abs) at 1400rpm grab you)
4) The engines combustion system is optimsed for maximum torque, rather than peak power (because that is choked by the restrictor
5) the wrc spec turbo is hugely efficient (as you expect for a £10k device!) Whereas a decent "normal" ball race turbo peaks at a total system efficiency (exhaust gas energy-turbine-CHRA-Compressor-intake charge density) of approx 55-60% a WRC turbine is "significantly" more efficent (can't say actual figure sorry). This means you get the maximum boost pressure for the lowest exhaust back pressure, and with the lowest air charge upheat (important for minimising intercooling work)
6) WRC engines have high static compression ratios (again, can't say how high, but it's V.high for an engine running several bar of boost), combined with combustion chambers optimised for a fast burn, they are very "spark" efficient, and run timings much closer to TDC than a normal "road based" boosted engine
7) The engines are designed and built to withstand high levels of detonation without damage, because they run into detonation in the course of normal runing (i've seen 160bar pmax with another 60bar of detonation on top of that !!)

All those factors (and several more too secret to talk about here ;-) mean a wrc engine has a huge peak torque capability. Fairly std "customer" spec WRC cars run something like 650Nm with a mild tune and none of the really tweaky "factory" parts.

[anonymous-user]

Of course you can do all that work on an unrestricted turbo engine too.

I think some people dont realise quite how much development has been going on in the "enthusiasts" world with these cars and engines on tight budgets, they are seriously quick pieces of kit.