Horsepower per litre

[Ayahuasca]

In order to avoid doing work today I pondered on this:


Merlin engine (start of WW2) - 37
(end of WW2) - 96

Griffith 500 - 64

2012 Formula One - 308

Ferrari F40 - 162

Porsche 993 - 76

Porsche 959 - 158

Land Rover Defender - 49

Wartsila-Sulzer RTA96-C - 5
(largest marine diesel)

Briggs & Stratton Lawnmower - 46

OS 10 LA model aircraft engine - 153



Maximum horsepower per engine litre of capacity. I believe all are forced induction apart from the 993, the TVR, the lawnmower and the model plane.

Any more interesting power per litres to ponder?

[otolith]

Power per kg of engine, or per litre of space that the engine occupies is more interesting.

[Layacable]

Lotus 71T ('80s F1 car).

602bhp per litre.


(In qualifying trim, at this state of tune the engine would only last 12 laps before needing a rebuild.)

Edited by Layacable on Tuesday 10th September 21:27

[anarki]

Evo 8 FQ-400 - 201bhp/litre

Efini spec RX7 - 212.3bhp/litre

Renault's 1.5 litre Turbo used in the 1986 F1 season. In qualifying trim, power could be boosted all the way to 1,500bhp, giving 1,000bhp/litre, although in the races, they ran at around 800bhp (a "mere" 533bhp/litre).

[Willy Nilly]

do jet/gas turbines have a displacement as such? They are internal combustion so must have

[otolith]

It's a meaningless metric for engines which work on radically different principles.

[Jimbo.]

Top Fuel dragster?

[Matt UK]

I think I read in EVO that the Ferrari 458 Speciale has the highest specific BHP for any nat asp engine.
597 bhp means the Speciale delivers 133 bhp-per-litre

And seeing as we are going to turbos for everything (rumoured even for the 458 replacement) this could well represent a high point for this type of road car engine.

Edited by Matt UK on Tuesday 10th September 21:41

[anonymous-user]

BMW S1000RR 193HP/litre. Normally aspirated and available from a showroom near you.

[Tango13]

The most powerful varients of the Merlin were the 133/134 models used in the post war de Havilland Hornet which put out 2030 HP which works out to 75 HP/Litre.

The Griffon put out 2420 HP but was a 37 litre engine vs the 27 litres of the Merlin so only generated 65.5 HP/litre

[leafspring]

1960 Land Rover petrol engine

77bhp / 2.286litre = 33.683bhp per litre

[Ayahuasca]

I guess lower HP per litre translates to less stressed, more relaxed and reliable performance hence the ultra relaxed marine diesel plodding its lonely way for thousands of miles across the oceans...

[chrissull]

Caparo T1?
Pretty sure that's mental bhp/litre, can't remember 100% but I think it's a 3.5l NA v8, with near 600 bhp.

[skyrover]

HP per litre is a pointless comparison as it completely ignores power delivery and usefulness

[SteveSteveson]

wormus said:

BMW S1000RR 193HP/litre. Normally aspirated and available from a showroom near you.

GSXR 600 - 206 bhp/l

Two strokes will do even better. An RS 125 makes 226 BHP/l

[rsox87]

Indeed they will - my TM K11b kart engine makes 32bhp from 100cc........at 20,500rpm!

A 231bhp RX8 makes 177bhp/l which is pretty good too. Small and efficient is the way to go for specific displacement, which is what makes the 4.5l 458 Speciale motor noteworthy - 133bhp/l from 4.5l is some going.

[stevesingo]

I like torque/litre as it is not dependant on rpms. Any NA over 90lb/ft per litre?

[CraigyMc]

stevesingo said:

I like torque/litre as it is not dependant on rpms. Any NA over 90lb/ft per litre?

Not feasible to get much above 100 on normal octane petrol, due to bmep.

Tells you nothing about torque at the wheels though, because of a fascinating device called a transmission.

C

[CraigyMc]

Jimbo. said:

Top Fuel dragster?

Very approximately, 1000bhp/litre.

C

[stevesingo]

CraigyMc said:

stevesingo said:

I like torque/litre as it is not dependant on rpms. Any NA over 90lb/ft per litre?

Not feasible to get much above 100 on normal octane petrol, due to bmep.

Tells you nothing about torque at the wheels though, because of a fascinating device called a transmission.

C

Not easy to quote tractive effort though, is it?

I've yet to see onything over 93-94 lb/ft litre on pump fuel. F1, I belive is about 96lb/ft litre.

Road cars, I think the max is 911GT3 at about 86lb/ft litre.