Maximum Torque Per Litre

[900T-R]

Pumaracing said:

Yeah well don't get me started on you bloody colonials and your reluctance to leave the 19th century and imperial measurements. It's high time we invaded you again, gave you a bloody good thrashing, annexed you back into the Queen's Commonwealth and dragged you kicking and screaming into the 21st century and stopped you being the only country in the world that can't cope with metric measurements.

While we're at it we could ban religion over there, abolish the Republican party which is near as dammit the same thing, release Sarah Palin back into the wild and then shoot the daft b1tch from a helicopter and stick a broom handle ten inches up Newt Gingrich's arse so he knows what his first two wives felt like after he shafted them.

[powerstroke]

Pumaracing said:

Stan Weiss said:

With most of the engines in the states listed in ci I have the same PITA using litre. Over here it is torque per ci.

Stan

Yeah well don't get me started on you bloody colonials and your reluctance to leave the 19th century and imperial measurements. It's high time we invaded you again, gave you a bloody good thrashing, annexed you back into the Queen's Commonwealth and dragged you kicking and screaming into the 21st century and stopped you being the only country in the world that can't cope with metric measurements.

While we're at it we could ban religion over there, abolish the Republican party which is near as dammit the same thing, release Sarah Palin back into the wild and then shoot the daft b1tch from a helicopter and stick a broom handle ten inches up Newt Gingrich's arse so he knows what his first two wives felt like after he shafted them.

Commie!!!!!

[Yuxi]

I worked on a gasoline engine family project last year which is due to go into production in about 8 years time, the premium high technology engine in this family makes 390Nm at 1500rpm and a peak torque of 418Nm, this engine is just under 1900cc. Thats 164ft/lb per litre. This is a high volume engine (200k units per annum +) not a race engine.

[DVandrews]

Yuxi said:

I worked on a gasoline engine family project last year which is due to go into production in about 8 years time, the premium high technology engine in this family makes 390Nm at 1500rpm and a peak torque of 418Nm, this engine is just under 1900cc. Thats 164ft/lb per litre. This is a high volume engine (200k units per annum +) not a race engine.

Naturally aspirated or forced induction?

Dave

[Yuxi]

DVandrews said:

Yuxi said:

I worked on a gasoline engine family project last year which is due to go into production in about 8 years time, the premium high technology engine in this family makes 390Nm at 1500rpm and a peak torque of 418Nm, this engine is just under 1900cc. Thats 164ft/lb per litre. This is a high volume engine (200k units per annum +) not a race engine.

Naturally aspirated or forced induction?

Dave

This variant has turbo and super chargers, dual cam phasing, cooled egr, DI and port injection, amongst other things

[900T-R]

DVandrews said:

Naturally aspirated or forced induction?

Dave

Let me take a wild guess...

[SWR Performance]

Well, I just read a magazine front page claiming a 418 bhp, 12 000 rpm NA Pinto. Guess that is very probable. Not.

Of the top of my head from self-built and dynoed I can list 142Nm from 1183cc's.. 5-valve head.

[Stan Weiss]

Pumaracing said:

Yeah well don't get me started on you bloody colonials and your reluctance to leave the 19th century and imperial measurements. It's high time we invaded you again, gave you a bloody good thrashing, annexed you back into the Queen's Commonwealth and dragged you kicking and screaming into the 21st century and stopped you being the only country in the world that can't cope with metric measurements.

While we're at it we could ban religion over there, abolish the Republican party which is near as dammit the same thing, release Sarah Palin back into the wild and then shoot the daft b1tch from a helicopter and stick a broom handle ten inches up Newt Gingrich's arse so he knows what his first two wives felt like after he shafted them.

Dave,
Please do not hold back and tell me what you real think.

The highest developed N/A 2 valve engine that I know of is the 500 ci NHRA Pro Stock engine. I am not sure how old these numbers are. Torque 840 @ 8100 / HP 1432 @ 9700 - If my conversion is correct 102.5 litre

Check it out on the dyno - http://youtu.be/rKH2RWZdZhM

Stan

[Mr2Mike]

Pumaracing said:

I have two thoughts on the matter. Firstly that perhaps the crossplane V8 crank arrangement makes some difference to the pulse tuning compared to flat plane 4 pot cranks. Secondly that maybe it's a matter of cylinder size. Big cylinders are harder to fill and obtain high bhp per litre figures from but they have a much larger ratio of volume to surface area than small cylinders and therefore possibly better thermal efficiency. i.e. less heat is lost to the cooling system. Maybe this helps the peak torque somewhat.

I'd be interested in any theory on the subject.

Everyone this side of the pond knows that American BHP's tend to be significantly smaller than European ones. Presuming that they don't have a different definition of RPM, that means their pounds-feet must be a bit under par so you get more of them to the cubic milliperch.

[Pumaracing]

Stan Weiss said:

Dave,
Please do not hold back and tell me what you real think.

The highest developed N/A 2 valve engine that I know of is the 500 ci NHRA Pro Stock engine. I am not sure how old these numbers are. Torque 840 @ 8100 / HP 1432 @ 9700 - If my conversion is correct 102.5 litre

Check it out on the dyno - http://youtu.be/rKH2RWZdZhM

Stan

They are certainly impressive but they don't use pump fuel. They run on racing fuel with octanes around 120 and CRs of 17 or so. We couldn't possibly build anything like that for normal classes of racing or fast road use. They also don't have to last very long which was another of my conditions. However even allowing for all that it's a pretty staggering torque per litre.

Do you have any views on the cross plane v flat plane crank issue?

[ringram]

Brummmie said:

504lbs/ft at the wheels with my 6823cc LS engine = 73.86lbsft with 15% losses is around 87lbs/ft at the fly?
Could be utter rubbish, it makes 80lbs/ft rear wheel, at idle 800rpm.

Not far off from you mate, from engine dyno 84ft/lb per litre

605ft/lb from 7.183L LS v8

[dom9]

SWR Performance said:

Well, I just read a magazine front page claiming a 418 bhp, 12 000 rpm NA Pinto. Guess that is very probable. Not.

Of the top of my head from self-built and dynoed I can list 142Nm from 1183cc's.. 5-valve head.

Would be interested to hear more about that Pinto! I remember all the Dave Walker articles in CCC converting the Pinto head to twin plug etc and they were struggling to see over 200bhp.

Assume the 1183cc engine was a Yamaha derived bike engine?

[SWR Performance]

dom9 said:

Would be interested to hear more about that Pinto! I remember all the Dave Walker articles in CCC converting the Pinto head to twin plug etc and they were struggling to see over 200bhp.

Assume the 1183cc engine was a Yamaha derived bike engine?

Well, the Classic Ford magazine (I think it was that mag, slips my mind at this time) had that on their front page this month. If it turns out to be boosted, it's output is not impressive, as I know people here going to scrappers, bolting on a VERY carefully mapped turbo kit to a bog stock Sierra IS engine they have successfully made 400 bhp without even taking the valve covers off. Mind you, it doesn't last forever, but it actually survive a couple hours at a track day or a weekend if they are lucky. At £150 a piece it's cheap fun.

Yes, Yamaha FZR 1000 ultra-big-bore one, running pump 98RON gas.

[Tango13]

Pumaracing said:

Do you have any views on the cross plane v flat plane crank issue?

I can remember back in the mists of time Audi being kicked out of the DTM for changing their V8 cranks from flat plane to cross plane or vice versa, can't remember what they did exactly just that they got booted.

Motorcycle engines have had some interesting things done with their crankshafts over the years, mostly on race bikes but some road bikes too.

Honda built a single crank V4 two stroke that fired all four cylinders within about 60~80 deg of crank rotation. The engine produced less peak horsepower than the previous engine that had two cylinders firing together but it had much easier to ride, was easier on it's tyres and was faster over race distance.

Laverda used to build three cylinder engines first with a 180 deg then later on 120 deg crankshafts which gave totally different engine characteristics, Triumph currently sell triples with IIRC 120deg cranks while Yamahas' R1 has a cross plane crank.

My 955cc triple puts out 71.2lbs ft of torque per litre while a Ducati 999cc V-twin is putting out 81lbs ft but both these outputs are at 8,000rpm plus.

[Mr2Mike]

Tango13 said:

Honda built a single crank V4 two stroke that fired all four cylinders within about 60~80 deg of crank rotation.

What model was that? I don't understand how a single crank 2 stroke V engine would work, since two cylinders would have to share the same crankcase space. This is why the RG500 was a square 4 and the RD500 was a twin crank V4 lookalike engine.

[spend]

Do they have any connection to that weird single derived from a twin that had an extra rod and pivot to do the balancing?

I did once have a madcap ponder whether you could make an oil pump out of that schema like 4 texas beam oil pumps in the sump

Pumaracing said:

Do you have any views on the cross plane v flat plane crank issue?

It would seem to me that having power surges every 90deg makes the difference, yet flat plane V8's don't seem to get the ample torque though (but maybe thats a marketing thing making them revvy, racey & bhp rich).

[Tango13]

Mr2Mike said:

Tango13 said:

Honda built a single crank V4 two stroke that fired all four cylinders within about 60~80 deg of crank rotation.

What model was that? I don't understand how a single crank 2 stroke V engine would work, since two cylinders would have to share the same crankcase space. This is why the RG500 was a square 4 and the RD500 was a twin crank V4 lookalike engine.

It was the NSR 500, each piston/con rod had its own big end journal and the engine had a realativly long crank.

The original NSR 500 fired a piston every 90 deg and had a power delivery that was utterly rabid. Then Honda changed the firing order so it fired two pistons together so the power delivery was like a twin and only slightly barking before realising a big single produced better traction and tightened the firing order up even more.

The Crankshaft on an RGV 250 or the JDM only TZR V-twin was just as long as a parallel twin RG or TZR for the same reason.

[Tango13]

spend said:

Do they have any connection to that weird single derived from a twin that had an extra rod and pivot to do the balancing?

I did once have a madcap ponder whether you could make an oil pump out of that schema like 4 texas beam oil pumps in the sump

The single with the extra rod and balance weight was the Ducati SuperMono although BMW have something similar with their F800 parallel twin.

[Huff]

The current Yamaha R1 has an inline 4 with a crossplane crank:

http://www.ashonbikes.com/cross-plane_crank

[VHPD]

DVandrews said:

The params I use on the spread sheet are..

4v engines
70-80 lb/ft road going
80-90 lb/ft serious road engine
90-94 lb/ft race engine

Dave

My Rover K series engine built by www.dvapower.com and mapped by Dave Walker made 89.81ft lbs/litre on Emerald's rollers. The real achievement of the Builder and Mapper is how well it behaves around town