RE: 800bhp Celica Is Fastest Car At Goodwood

[anonymous-user]

The company i worked for doing WRC dev spent £1.2M on dyno time alone in 1 year, and employed the best engineers in the world. With all due respect, the guys building the high boost specials do an amazing job with the limited budgets they have, but it is still a pretty far cry from "profesional" motorsport. For example, we built our own gas turbine "gas generator" rig so we could efficiency test turbochargers and pick the best ones (and that's on top of the full turbo manufacturer support/data etc!)

If you are simply considering maximising specific torque output (i.e. max BMEP / NM/l) then i suggest that a factory wrc engine is about as good as it gets ;-)

[chuntington101]

Max_Torque said:

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???

Max, thanks agian mate, you never fail to imspress with your knowlage.

I have to agree with you on the high boost and high comp. ratio on boost engines. i have had the pleasure of reading a few posts bya US drag race engine builder thats sister company works in the engine R&D business. His engines often run over 40psi (GM LS based engines) and yet he still run VERY HIGH comp. ratios. Like you though he wont give any bloody info away! lol

As for the 2.3ltr motors making well over 800lbsft of torque, it was built by Norris Designs (simon) for their Time Attack Evo i think. Simon has an in house engine dyno but thats about all the info i have.

On a side note, dose anyone know if this Celica is spaceframed or still the original chassis?????

Chris.

[snowy slopes]

I think Jonny Milner's orange beastie is on a standard chassis, just much modified, but i stand to be corrected

[anonymous-user]

Max_Torque said:

The company i worked for doing WRC dev spent £1.2M on dyno time alone in 1 year, and employed the best engineers in the world. With all due respect, the guys building the high boost specials do an amazing job with the limited budgets they have, but it is still a pretty far cry from "profesional" motorsport. For example, we built our own gas turbine "gas generator" rig so we could efficiency test turbochargers and pick the best ones (and that's on top of the full turbo manufacturer support/data etc!)

If you are simply considering maximising specific torque output (i.e. max BMEP / NM/l) then i suggest that a factory wrc engine is about as good as it gets ;-)

Well of course, but these highly developed restricted engines are not going compete against an enthusiast or budget profesional outfit running unrestricted. In their own world they are of course very impressive.

Very much looking forward to seeing what Andy Forrest does this year with his new Impreza. His previous 2.3 had his road legal STi5 topping out at 210MPH at Elvington with standard aero (impreza's are like bricks ), doing 164MPH at the 1/4 mile from a standing start. His new project is again a road legal full shell Impreza running with a Legacy derived 3.6 H6 engine with twin garrett GT30R's, it should move on the performance of these cars a fair bit, giving a fairly low stress 1000BHP/tonne, which is pretty good in a road legal tin top.

[anonymous-user]

johnfelstead said:

Well of course, but these highly developed restricted engines are not going compete against an enthusiast or budget profesional outfit running unrestricted. In their own world they are of course very impressive.

Very much looking forward to seeing what Andy Forrest does this year with his new Impreza. His previous 2.3 had his road legal STi5 topping out at 210MPH at Elvington with standard aero (impreza's are like bricks ), doing 164MPH at the 1/4 mile from a standing start. His new project is again a road legal full shell Impreza running with a Legacy derived 3.6 H6 engine with twin garrett GT30R's, it should move on the performance of these cars a fair bit, giving a fairly low stress 1000BHP/tonne, which is pretty good in a road legal tin top.

I was not comparing WRC engines to "Unrestricted" ones in terms of peak power (because of course they can't compare in terms of ultimate output). I was comparing peak specific torque output, where a WRC engine is NOT restricted.

The point was to in response to claims of 800lbft from a 2.3litre engine, claims which are suspect imo. The absolute "world class" cutting edge highly boosted high specific torque output small capacity engine IS a factory WRC specification engine.

if, imo, it is dificult to get those high BMEP's (>50bar) from one of those, how are the "aftermarket" people managing?? (and who is chekcing the accuracy and validity of their claims***)



btw here is the "Choked restrictor Boost curve" for a WRC restricted specification engine (note, this is not "real data" but normalised data for confidentiality reasons!)

Engine Speed[rpm]	MAP[abs]	Est. Torque[Nm]
1000	1075	1912
2000	540	960
3000	358	796
4000	269	598
5000	215	478
6000	179	398

for this you can see that at anything less than 3000rpm a "typical" WRC engine is not "inlet restricted", and with ALS, these engines can run "full" boost right down to idle rpm ;-)

• * lets face it, in the world of the internet and car "tuning" lots and lots of people make outlandish claims for the performance of their engines ;-) Most of which, when scrutinised with a critical eye fail to hold water............

Edited by anonymous-user on Friday 8th July 12:36

[_dobbo_]

Max_Torque said:

btw here is the "Choked restrictor Boost curve" for a WRC restricted specification engine (note, this is not "real data" but normalised data for confidentiality reasons!)

Engine Speed[rpm]	MAP[abs]	Est. Torque[Nm]
1000	1075	1912

Is that right? 1912nm at 1000 revs?

[Dagnut]

_dobbo_ said:

Max_Torque said:

btw here is the "Choked restrictor Boost curve" for a WRC restricted specification engine (note, this is not "real data" but normalised data for confidentiality reasons!)

Engine Speed[rpm]	MAP[abs]	Est. Torque[Nm]
1000	1075	1912

Is that right? 1912nm at 1000 revs?

That means it's making 268bhp at 1000rpm.....pretty impressive but sounds right that's what makes WRC cars so quick

[snowy slopes]

johnfelstead said:

Well of course, but these highly developed restricted engines are not going compete against an enthusiast or budget profesional outfit running unrestricted. In their own world they are of course very impressive.

Very much looking forward to seeing what Andy Forrest does this year with his new Impreza. His previous 2.3 had his road legal STi5 topping out at 210MPH at Elvington with standard aero (impreza's are like bricks ), doing 164MPH at the 1/4 mile from a standing start. His new project is again a road legal full shell Impreza running with a Legacy derived 3.6 H6 engine with twin garrett GT30R's, it should move on the performance of these cars a fair bit, giving a fairly low stress 1000BHP/tonne, which is pretty good in a road legal tin top.

Christ on a bike, that's going to be one mental road legal car

[chuntington101]

Max, is there any publicly avalaible info on these external anti lag devices (i asume you mean like the scooby rocket box)??? It would be really intresting to find out more about them. Obviously i know you probably cant shed much light on it (or can you??? ).

and here is an off topic and wacky idea for you, have you ever come accross water being used for anti lag purposes? There was a idea of spraying a VERY fine mist of water into the exhaust manifold. hopefully the water would turn to steam and thus exspand around about 4000 times its original volume. This added volume would then help drive th turbo and keep it boost. Also if used in conjunction with normal anti lag (probably needed to get EGTs up high enough to flash the water to steam) it would help cool the EGTs and take some (thermal) presure off the turbo.

Just a wacky idea.

Chris.

[snowy slopes]

chuntington101 said:

Max, is there any publicly avalaible info on these external anti lag devices (i asume you mean like the scooby rocket box)??? It would be really intresting to find out more about them. Obviously i know you probably cant shed much light on it (or can you??? ).

and here is an off topic and wacky idea for you, have you ever come accross water being used for anti lag purposes? There was a idea of spraying a VERY fine mist of water into the exhaust manifold. hopefully the water would turn to steam and thus exspand around about 4000 times its original volume. This added volume would then help drive th turbo and keep it boost. Also if used in conjunction with normal anti lag (probably needed to get EGTs up high enough to flash the water to steam) it would help cool the EGTs and take some (thermal) presure off the turbo.

Just a wacky idea.

Chris.

Im sure i've seen an ecort rs turbo running a water injection thingy as a charge cooler type device, so i guess thats what you mean??

[Dagnut]

snowy slopes said:

chuntington101 said:

Max, is there any publicly avalaible info on these external anti lag devices (i asume you mean like the scooby rocket box)??? It would be really intresting to find out more about them. Obviously i know you probably cant shed much light on it (or can you??? ).

and here is an off topic and wacky idea for you, have you ever come accross water being used for anti lag purposes? There was a idea of spraying a VERY fine mist of water into the exhaust manifold. hopefully the water would turn to steam and thus exspand around about 4000 times its original volume. This added volume would then help drive th turbo and keep it boost. Also if used in conjunction with normal anti lag (probably needed to get EGTs up high enough to flash the water to steam) it would help cool the EGTs and take some (thermal) presure off the turbo.

Just a wacky idea.

Chris.

Im sure i've seen an ecort rs turbo running a water injection thingy as a charge cooler type device, so i guess thats what you mean??

He's taking about creating vapour in the manifold..which doesn't sound ideal for the turbo..but I could be wrong just guess work

[snowy slopes]

Ahhh, sounds very complicated to me

[John D.]

grippa said:

FOS Turning into Macdonalds drive thou

[anonymous-user]

_dobbo_ said:

Max_Torque said:

btw here is the "Choked restrictor Boost curve" for a WRC restricted specification engine (note, this is not "real data" but normalised data for confidentiality reasons!)

Engine Speed[rpm]	MAP[abs]	Est. Torque[Nm]
1000	1075	1912

Is that right? 1912nm at 1000 revs?

that curve is the boost you would "have" to run to choke the restrictor across the whole rpm range on a 2 litre 34mm restricted engine. As you can see, at say 1000rpm, you would have to apply a little over 10bar boost to do this (which would make circa 1900Nm if the engine could withstand it)

In reality, the engines cannot withstand those sorts of boost pressures and the resulting BMEP's. Basically, that table illustrates the point that a WRC engine is NOT restricted by the, er restrictor at low rpm!

As previously mentioned, a "typical" wrc factory engine can make >700Nm peak torque.

[anonymous-user]

chuntington101 said:

Max, is there any publicly avalaible info on these external anti lag devices (i asume you mean like the scooby rocket box)??? It would be really intresting to find out more about them. Obviously i know you probably cant shed much light on it (or can you??? ).

and here is an off topic and wacky idea for you, have you ever come accross water being used for anti lag purposes? There was a idea of spraying a VERY fine mist of water into the exhaust manifold. hopefully the water would turn to steam and thus exspand around about 4000 times its original volume. This added volume would then help drive th turbo and keep it boost. Also if used in conjunction with normal anti lag (probably needed to get EGTs up high enough to flash the water to steam) it would help cool the EGTs and take some (thermal) presure off the turbo.

Just a wacky idea.

Chris.

RE: als combustor systems, er, NO! (people keep that kind of thing very close to their chest! (the "trick" is developing a combustor flame holder that correctly anchors the flame front across a wide range of inlet massflows and temperatures (because you want it to stay lit across the engine speed and load range. The second trick is developing a closed loop turbo shaft speed control system which can manage the energy split between the engine combustion system and the "gas producer" system........)

Generally speaking, their would be little advantage to injecting water into the exhaust manifold, as when it vapourises it will cool the exhaust gas stream, so "total" energy will remain the same (higher Mdot but lower temp, PV=nRT etc) and turbines are primarily an "delta temperature" device (i.e. the exhaust stream expands across the turbine, reducing in temperature and releasing energy to the turbine blades. they are not "blown around" by the gas to any real extent)

However, i could see a case for limiting pre-turbine temps for some applications, so it might work in some limited cases. (what it won't do is add more "energy" into the exhaust stream, but it could allow you to use more of that energy)

[anonymous-user]

Max_Torque said:

if, imo, it is dificult to get those high BMEP's (>50bar) from one of those, how are the "aftermarket" people managing?? (and who is chekcing the accuracy and validity of their claims***)

Fuel helps, aftermarket tuners are not limited to an 102RON unleaded control fuel, you have people making their own brews of fuel which does push the performance atainable higher.

You are of course correct that a lot of figures are nonesence, but there are a few UK guys out there in the aftermarket world that are making serious performance engines work and produce results.

When i first started driving Subaru's in the 90's 300BHP was the suposed limit for a "chocolate" Impreza engine, we are now seeing 500BHP as normal in a road car and circa 900BHP out of a WRC technology based 2.0 with the apropriate externals.

The most popular configuration of choice for high power apps is the 2.3, because you can use the larger bore special sand cast closed deck block Subaru produced as a start point, combined with a long stroke crank to obtain the 2.3.

My own choice for my road car was to use a semi closed deck 2.0 that was standard in my PWRC homologated engine, but use a 2.5 crank with a bespoke Mahle forged high compresion piston. It running the stock external twin scroll setup that was PWRC homologated so is not a high power producer at only 354BHP, but it's producing nice torque of 542NM @ 3500rpm. The HC config with the relatively small twin scroll turbo makes for a very responsive everyday driver.

I've found with this pretty mild engine using a small 30% mix of 120RON oxigenated fuel mixed with SUL allows an extra 30NM at the same boost with an extra 6 degrees ignition dialed in. The serious tuners are playing around with some far from stock based fuels.

[Dagnut]

johnfelstead said:

Max_Torque said:

if, imo, it is dificult to get those high BMEP's (>50bar) from one of those, how are the "aftermarket" people managing?? (and who is chekcing the accuracy and validity of their claims***)

Fuel helps, aftermarket tuners are not limited to an 102RON unleaded control fuel, you have people making their own brews of fuel which does push the performance atainable higher.

You are of course correct that a lot of figures are nonesence, but there are a few UK guys out there in the aftermarket world that are making serious performance engines work and produce results.

When i first started driving Subaru's in the 90's 300BHP was the suposed limit for a "chocolate" Impreza engine, we are now seeing 500BHP as normal in a road car and circa 900BHP out of a WRC technology based 2.0 with the apropriate externals.

The most popular configuration of choice for high power apps is the 2.3, because you can use the larger bore special sand cast closed deck block Subaru produced as a start point, combined with a long stroke crank to obtain the 2.3.

My own choice for my road car was to use a semi closed deck 2.0 that was standard in my PWRC homologated engine, but use a 2.5 crank with a bespoke Mahle forged high compresion piston. It running the stock external twin scroll setup that was PWRC homologated so is not a high power producer at only 354BHP, but it's producing nice torque of 542NM @ 3500rpm. The HC config with the relatively small twin scroll turbo makes for a very responsive everyday driver.

I've found with this pretty mild engine using a small 30% mix of 120RON oxigenated fuel mixed with SUL allows an extra 30NM at the same boost with an extra 6 degrees ignition dialed in. The serious tuners are playing around with some far from stock based fuels.

Great info..a lot of people using NF octane booster as well, really makes a difference.

[anonymous-user]

NF works pretty well as a basic octane booster, the nice thing about using that in a Subaru is the ECU has a very responsive active knock control strategy, so when it senses a less det prone fuel it will advance the ignition to take advantage of it. Using an OB in some cars loses you performance because it slows the fuel burn down, if the engine cant alter it's timing for that you get a less eficient combustion.

I run two maps in my car, switching between them depending on which fuel is in use, the ECU then uses these base maps and fine tunes them actively to take acount of conditions and any small differences in the fuel batches.

I could pick up more torque if i wanted, as this PWRC spec turbo will produce 2.2BAR mid range with the waste gate closed, but i've settled on 1.8BAR being plenty on the spec of engine i have. It wont produce any more power though as it's flow limited, the engine can rev to 8000rpm but there is no point taking it past 6500rpm, by which time it's down at 1BAR of boost.

[Dagnut]

johnfelstead said:

NF works pretty well as a basic octane booster, the nice thing about using that in a Subaru is the ECU has a very responsive active knock control strategy, so when it senses a less det prone fuel it will advance the ignition to take advantage of it. Using an OB in some cars loses you performance because it slows the fuel burn down, if the engine cant alter it's timing for that you get a less eficient combustion.

I run two maps in my car, switching between them depending on which fuel is in use, the ECU then uses these base maps and fine tunes them actively to take acount of conditions and any small differences in the fuel batches.

I could pick up more torque if i wanted, as this PWRC spec turbo will produce 2.2BAR mid range with the waste gate closed, but i've settled on 1.8BAR being plenty on the spec of engine i have. It wont produce any more power though as it's flow limited, the engine can rev to 8000rpm but there is no point taking it past 6500rpm, by which time it's down at 1BAR of boost.

Are you running a simtec ecu?

[chuntington101]

Max, how effective is a conventional anti lag system in comparison to these external combustion chambers? Also how effective would a wrc style anti-lag system be with a much larger turbo, say something like a garrett gt42rs sized turbo?

Thanks,

Chris.