Which normally aspirated engine leaves the highest bhp/liter output?

Peter,

My CBR1000RR has about 178 bhp at the flywheel which equates to 157bhp at the back wheel. So effectively I'm getting serious bhp/ltr. I think that the S2000 may have one of if not the highest bhp/ltr in the normally aspirated car world. The McLaren F1 and BMW M3 are both comfortably over 100bhp/ltr

Matt

 

lets not forget the 360, with 400hp and 3.56litters....

 

F1 Ferraris have 300hp/liter naturally aspirated. 3.0 with 900hp. Of course with boost top fuel dragsters have almost 1000hp/liter. i think they are 8.0 liters with almost 8000 hp. Takes alot of hp to go 0-150 in 1.5 seconds in 200 feet.

 

Blowers and turbos don't count, because they effectively make the engine bigger without actually making it physically bigger.

So definitely Honda S2000

 

The S2000 is, to my knowledge, the winner.

The Stradale is not far behind at 118bhp/liter.

 

So are you ignoring Matt's post about motorcycles? Some naturally aspirated liter bikes are pushing 170 crank hp or 170hp/liter. However, most of the 600cc bikes are making 120 hp so they are around 200hp/liter stock. All without outside help and for very reasonable money.

Larry

 

Mentioning F1 cars?

Ok then... 250cc motogp bikes are getting almost 100 hp. Hows that?

Theres QUITE A FEW people with literbikes who can put down 190hp to hte rear wheel. No NOS, or blowers.

 

It's amazing how much farther ahead the bike makers are than the car makers. I think they have more environmental restrictions that the bike makers.

 

True, but automotive fuel injection and engine management is probably 10-15 years ahead of bikes. A bike's advantage is being able to spin high rpm (same with F1), if you talked torque per liter it would be a slightly different story.

Larry

 

Well ... my snowmobile is a 440cc pushing 97hp ... that's 220hp/L. My bike is around 60-65hp for 250cc, which makes it 260hp/L. My old 80cc had 27hp ... woohoo 330hp/L. I win. What? No 2 strokes? Damn.


Anyone into boats PWCs and co. to tell us how these engines perform. They are way ahead as far as efficiency goes, iirc.

 

Why?. All modern bikes have engine management systems and fuel injection ... even Ducati!


To play this game you need to have separate categories for each type of engine, ie:

4 stroke petrol engine - Some MotoGP race engine, actually no a F1 engine.
2 stroke petrol engine - Some 125 or 250cc GP race engine.
4 stroke turbo petrol engine - BMW F1 engine - 1500hp out of 1.5 ltrs. Debateable whether it was breathing petrol
4 stroke supercharged petrol engine - Good question.
4 stroke supercharged any fuel engine - Top Fuel dragster.
4 stroke diesel engine - ?
2 stroke diesel engine - ?
4 stroke turbo diesel engine - ?
4 stroke supercharged diesel engine - ?
etc.

You must compare like with like!
Pete
ps: Bikes make more power simply because their service intervals are heaps shorter and owners accept that. Having your Ferrari services every 1000 miles is not acceptable to the poncy cafe larte (sp?) crowd

 

I am assuming you have an RGV250 or RS 250??? Am I correct?

 

Not so. With regular oil/tire changes, and a properly lubed chain... You shouldn't be running into any problems at all. Those japanese sportbike engines are made to last forever. (probably longer than your ferrari)

 

Hmmm, we seem to have miscommunicated. I said that bikes have shorter service intervals NOT that they would not last.

A Ducati in Australia is to be serviced every 1000 miles (1600 km), my Toyota car on the other hand is serviced every 10,000 km. I do not know the service intervals for Japanese bikes but I still believe it is a lot shorter than the equivalent car.

To make cars last the longer distance to the next service intervals DOES mean they have to be softer tune.

Pete

 

Nope. Make that a CR 250 (yup, dirtbike). And it's not stock . The bike is competitive at Canadian National level (Jean-Sebastien Roy's ex-bike). The rider isn't! LMAO

edit - btw, I go by TMR's quotes for power. Personally I can only say my bike is a 2000, and is heaps faster than a top shape piped 2004 CR250.
On the track or on the trails it's "holy-crap-the-tree-is-getting-way-to-close-no-ouch" fast. Has more low end than a 450cc thumper, and yet has that typical 2 stroke top end boost. I love it.

 

Horsepower = (Foot*Lbs)(RPM)/5252

Given constant torque, an increase in RPM will always increase power. Torque becomes harder to maintain the higher up the engine revs though.

 

PSk,

My Blade has oil service intervals of 8k miles. However, I'll be changing the oil every 4k miles as I believe that no matter how good oil technology has become, it still requires changing regularly when using high load and rpm.

Cars do tend to run for longer between services, unless it's a Mitsubishi Lancer Evolution which here in the UK has 4.5k mile intervals! However, the gap is getting closer.

I'd say that some of the 600cc sports bikes would have the highest specific N/A output, but then they need 15,000 revs to get there.

Matt

 

Most bike manufacturers have just started using FI regularly over the last few years...when was the last time you saw a new car with carbs? That's my only point, cars have been using it longer and it is more refined. Bikes will get there especially as the emissions requirements get more strict.

Larry


PS - I assume you are talking about valve adjustment intervals being closer together for bikes. While that is true, I don't see where bikes need a motor-out service to replace belts every couple of years

 

IF you believe the CS makes 118 HP/L, then that is the winner, as the Honda now sports a 2.2 L making the same 240 HP, so really it has about...110 hp/l. I liked the 2.0 I had better than the 04, and thought it looked better too!

 

LOL ... yes true. I think Ducati are the only manufacturer to use rubber bands to drive the cams

Pete