What is Aston Martin up to?

[ss_collins]

So th homologated engine route looks a good way to go... but bear in mind there are these rumours that won't go away of a Ferrari LMP...

[Bentley03]

Originally Posted by ss_collins

So th homologated engine route looks a good way to go... but bear in mind there are these rumours that won't go away of a Ferrari LMP...

You're not trying to tell us this thread should be renamed 'What is Ferrari up to?', are you?

[gwyllion]

Or Maserati finally doing it right by building a real prototype

[ss_collins]

I'm not saying anything. Though I strongly suspect that a new works LMP1 has been in a wind tunnel - and it may be yellow.
Anyway - I think the homologated engine rules were introduced at the Italians behest...

[ger80]

Originally Posted by ss_collins

I'm not saying anything. Though I strongly suspect that a new works LMP1 has been in a wind tunnel - and it may be yellow.
Anyway - I think the homologated engine rules were introduced at the Italians behest...

But the yellow car is not an italian car?

[gwyllion]

Originally Posted by ger80

But the yellow car is not an italian car?

... and has a bigger displacement than 6 liter.

[Francesco]

the main problem with Maserati engine for Le Mans is that it need to be built in 1000 units in a year... and also counting all the enzo + all the MC12 you come near to 500 cars...

maybe a good engine would be the one in the 599 GTB Fiorano which has a lot in common with the Enzo-Mc12, and which actually can be seen in some road going cars with 630+ Cv

[ss_collins]

It looks like the Autosport launch will be the GT2 Vantage then - not ground shaking... artists impression on various sites including racecar (news section)

Or is there more to come... (in the voice that makes hindy jump and down and go tellmetellmetellme)

[AMT]

Originally Posted by David L

Thanks very much for clearing this up AMT..

It was Robin Hamilton that was widely quoted as saying that the T385 was a derivative of the T600..

Regards

That doesn't surprise me.

[Gil Abobeleira]

Originally Posted by gwyllion

... and has a bigger displacement than 6 liter.

Hmmmm, something along the lines of this one, then:

[canam]

Originally Posted by knighty

Yup, just worked it out along the same lines too, the data I have below is from race engine magazine when they interviewed Jason Hill about the Prodrive GT1 aston engine project.

2005 AM V12 with 2 x 31.2mm restrictors = 1530mm area = 585bhp

2006 AM V12 with 2 x 30.8mm restrictors = 1490mm area = 570bhp

2007 AM V12 with 2 x 30.7mm restrictors = 1480mm area = 570bhp

Divide the power by the restrictor area and I get an average ratio of 0.383……therefore for 2008 P1 engine using a homologated GT1 base motor…...

2 x 33.7 P1 homologated GT1 restrictors = 1784mm = 683bhp

2 x 34mm P1 homologated GT1 restrictors (Aircon) = 1816mm = 695bhp

So yes, I now agree!......as the P1 engine will be spinning faster that in its GT1 guise I'd also say it was good for just under 700bhp

If I was Mr Judd I'd be pretty peeved looking at those numbers :-(

These numbers make very interesting reading; however, where would the Aston engine be revving to get this power (as the displacement will not change) and what will its fuel consumption look like. Although the diesels have overcome this to a degree, how much heavier would the Aston motor be over, say, a Judd.

[phoenix]

Originally Posted by canam

These numbers make very interesting reading; however, where would the Aston engine be revving to get this power (as the displacement will not change) and what will its fuel consumption look like.

All other things about the engine remaining equal, the engine will have to rev 22% faster to generate 695 bhp than it was spinning to generate 570 bhp. Fuel consumption would increase by the same amount.

[Truckosaurus]

Would the larger restrictors not mean the extra power is released without having to rev higher?

[phoenix]

Originally Posted by Truckosaurus

Would the larger restrictors not mean the extra power is released without having to rev higher?

No, because restrictors are effectively rev-limiters - they restrict the engine breathing beyond a certain limit putting an effective cap on power by limiting revs.

[HORNDAWG]

Originally Posted by Truckosaurus

Would the larger restrictors not mean the extra power is released without having to rev higher?

Yes. With a larger restrictor you get more air, consequently you can now feed it more fuel because of the greater volume of air. Remap the ignition curve and timing and at a given (set) rpm you could/should produce more power as you now can burn more fuel. At least that is my rudimentary knowledge of how it works. Fuel+air=power, up to the given mechanical limitations of the engine you are working with.


L.P.

[Truckosaurus]

Originally Posted by Truckosaurus

Would the larger restrictors not mean the extra power is released without having to rev higher?

Originally Posted by phoenix

No

Originally Posted by HORNDAWG

Yes

Anyone like to make a Casting Vote?

[canam]

I think it is necessary to consider the size of the engine. With a given restrictor and engine size, the air/fuel mixture is optimised at which point the power peaks. Beyond this rev level, the mixture is suboptimal--overfuelled. A bigger restrictor will have no discernable impact on power below this rev level as the air/fuel mixture is balanced up to that limit. Increased air flow allows for increased fuel usage--which IMO is only beneficial if the revs are higher.

You need higher revs to get additional power. That's my vote.

[JAG]

Originally Posted by phoenix

All other things about the engine remaining equal, the engine will have to rev 22% faster to generate 695 bhp than it was spinning to generate 570 bhp. Fuel consumption would increase by the same amount.

570bhp appears incredibly conservative, the absolute minimum quoted is always 600bhp, and as stated above, I would think they're closer to 620bhp.

I don't recall the V12 LMR reving much higher than the Aston V12, despite producing over 650bhp with the same displacment.

WRC and rallycross engines are very similar, but the 34mm restrictor on a WRC car produces 350bhp, the rallycross car more like 550bhp wih a 38mm-40mm restrictor.

I don't believe a rallycross cars revs anymore than 1500rpm higher than the wrc machine, if that.

[Francesco]

AM has used 2 VERY different engines during the season... the "normal" spec. used by Team Modena, Jet Alliance ecc.. and the "EVO LM" pack used from Le Mans by official team, Larbre and from Spa 24 from BMS... the "evo" engine is at least 20Hp more powerful from what i know...

[canam]

Originally Posted by JAG

WRC and rallycross engines are very similar, but the 34mm restrictor on a WRC car produces 350bhp, the rallycross car more like 550bhp wih a 38mm-40mm restrictor.

I don't believe a rallycross cars revs anymore than 1500rpm higher than the wrc machine, if that.

Are these turbo engines or NA units? the 34mm restrictor was imposed on forced induction engines I beleive. The link between revs and power is broken as you have a third variable--boost pressure.

[FIRE]

WRC = turbo

[gwyllion]

Originally Posted by Francesco

AM has used 2 VERY different engines during the season... the "normal" spec. used by Team Modena, Jet Alliance ecc.. and the "EVO LM" pack used from Le Mans by official team, Larbre and from Spa 24 from BMS... the "evo" engine is at least 20Hp more powerful from what i know...

Maybe because they ran with air conditioning and thus got a bigger restrictor

[phoenix]

Originally Posted by JAG

WRC and rallycross engines are very similar, but the 34mm restrictor on a WRC car produces 350bhp, the rallycross car more like 550bhp wih a 38mm-40mm restrictor.

I don't believe a rallycross cars revs anymore than 1500rpm higher than the wrc machine, if that.

With turbo engines such as these things are a little different - although the limit is still to the air flow.

For example: a 34 mm restrictor may allow a 2 litre engine to generate 306 ft/lb and 350 BHP at 1.5 bar boost at 6000 rpm. Increasing the restrictor size to 40 mm allows 38% more airflow, so the engine could be fed the same level of boost at higher rpm, or more boost at the same rpm. Or a combination of both - 2 bar at 7500 rpm, for example, would require approximately a 38% increase in airflow.

One way or another, the engine with the larger restrictor will be able to breath more air, burn more fuel and make more power.

To get substantially more air into a normally aspirated race engine per minute would normally require the engine to rev higher as there is no boost pressure to adjust and there is no other simple way of getting more air in.

[dj choc ice]

yes, WRC engines are 2.0 litre 4 cylinder single turbo, around 300-350bhp

[AU N EGL]

DBR9 In keeping with GT1 regulations, the AM DBR9 uses the DB9 road car’s bonded-aluminium chassis, but with the addition of a Prodrive-designed steel roll cage.

The race engine has been designed by our engineers and is also built on site. As regulations dictate, it is based on the DB9’s 6-litre V12 aluminium cylinder block and head. All the internals are then purpose-designed for competition use, including a new crank shaft, con rods, pistons, cylinder linings and cam shafts. Even with the standard FIA air restriction, the engine still produces more than 600bhp and more than 700 Nm of torque.

DBS9 Our engineers have tuned the standard 12 cylinder, six litre engine to produce approximately 550bhp.

Wasn't the DBR9s red lining about 7000 rpms?

I also think Jag is correct at 620bhp being the most list as the hp.

Fuel Consumption? Wild Guess here, 1.5 km / Liter or 100 liter tank and runs about 50 min on a tank of fuel ??