Faster car with less than 100 kg/h fuel flow

[Zynerji]

Let's go 1.5L v10 with a 2.5 Bar twin turbo, MGU-h/k.

[FW17]

I suppose they would use Direct injection, TJI and KERS to help the fuel efficiency. VIL, VVT and VVL can also be applied to get a few more percentage fuel savings..

Granted. An F1 V10 done right would probably still finish the race ahead of the turbos with 100kg of fuel since it would still be lighter by 100kgs!

Without the turbo and recovery system, a V10 3.0 would be very inefficient. And have a lot less power on 100kg/h fuel then the current hybrids. A rough estimate, if the V6TH has 50% efficiency and a V10 around 30, with the supposed 1000HP, a V10 would have only 600HP on 100kg/h...

It is not fair to use the old fuel consumption figures because I am assuming we modernize the V10s. The V10 was heavily limited by regulations. Technology has advanced so much since then. I suspect one of the reasons the V10 had used a tonne of fuel because it was advantageous for other uses such as cooling and combustion stability. I know a developed V10 with better cooling design, direct injection and other technolgies would be much more efficient.

We are also talking about overall speed as well. Assuming we had the cars weighing 600kg again they would be so much lighter that you won't need to turn the engine up all the time so some savings there too.

Toyota ran the V8 in lmp1 for quiet a few years against turbo cars, before switching to turbo engines.

[PlatinumZealot]

Yes. And it was fairly competitive. Let's imagine restrictions removed, lesser weight gets you really far in F1. 100kg is worth about 5 seconds of laptime.

[Jolle]

Just a small point... F1 went from turbo engines to NA not because they were faster (They were not) but because chargers were banned.

To get, let’s say, 1000 HP, the most efficient way (in size, weight and fuel economy) is a small ICE with a massive turbo.

[gruntguru]

A turbo isn’t an energy recovery system in the same sense as a KERS system; the energy recovered is used to force more air into the engine, but to burn that air you still need more fuel...

To a limited extent a turbocharger can do some compounding. If MAP is higher than EAP the pumping cycle of the engine will go positive and increase crankshaft power at zero cost. This is rarely the case in road car engines but can be significant in large stationary and marine engines.

One major disadvantage of the turbocharged engine is that it must run lower compression ratios; that actually hurts peak efficiency at full throttle......The advantage of the turbocharged engine is mainly at part-throttle operation where the lower compression ratio of the pistons results in less engine resistance, and therefore better economy (that’s why a small turbocharged engine is a good choice for a family car that is normally used at part-throttle around towns and on the motorway).

The part throttle advantage is not due to lower compression but rather the downsized engine. Less friction, less throttling loss.

Efficiency at peak load depends mostly on AFR. Turbo road cars typically run very rich at full load, to suppress detonation and reduce thermal stress. Formula 1 run very lean, also to suppress detonation and reduce thermal stress but mostly to improve thermal efficiency (and the difference in TE is massive - 30% vs 45% or more - a 50% improvement over the road car)

[PlatinumZealot]

I feel the naturally aspirated ruleset should havd been relaxed to allow innovations. There is so much that was not explored because of restrictions. I am thinking variable valve timing could have allowed pseudo Atkinson cycle operation to aid fuel efficiency in race stints. Things like variable intake runners.. Variable valve lift... Efficiency of 40% or therabouts might have been had.. Then add an advanced KERS and Advanced battery storage.

[ENGINE TUNER]

I feel the naturally aspirated ruleset should havd been relaxed to allow innovations. There is so much that was not explored because of restrictions. I am thinking variable valve timing could have allowed pseudo Atkinson cycle operation to aid fuel efficiency in race stints. Things like variable intake runners.. Variable valve lift... Efficiency of 40% or therabouts might have been had.. Then add an advanced KERS and Advanced battery storage.

Fuel efficiency didn't matter during the na period because refueling was allowed for most of it. Add in all those expensive and complicated systems and they still wouldn't approach the efficiency of the current PUs. Why throw all that lipstick on pigs that are ready for slaughter? Turbo rendered na obsolete in the 80s, why try to resurrect dinosaurs? Because you liked the sound of their roar? It is illogical. 1988 turbo motors were both fuel(150L) and boost limited(2.5bar) and still won EVERY race against unlimited 3.5L na engines. The na goose was cooked, if was nothing but foolishness to ban the turbos for 89.

[ENGINE TUNER]

Let's go 1.5L v10 with a 2.5 Bar twin turbo, MGU-h/k.

Why when a 1.5L 4 cylinder single turbo would make more power, use less fuel and weigh less and require less cooling?

[Tommy Cookers]

To get, let’s say, 1000 HP, the most efficient way (in size, weight and fuel economy) is a small ICE with a massive turbo.

if eg a 'massive turbo' means more than 5 bar MAP you would need a 2 stage compressor ie a 2 spool turbo if ...
you want to recover energy directly - the turbo is very efficient only at relatively low pressure ratio per stage

and ... doesn't the current turbo design also get help from the H that a stand-alone turbo design wouldn't have ?

btw and fwiw ....
once I signed off the dynamic response etc of a 3 stage air system that internally reached 216 bar

[Zynerji]

Let's go 1.5L v10 with a 2.5 Bar twin turbo, MGU-h/k.

Why when a 1.5L 4 cylinder single turbo would make more power, use less fuel and weigh less and require less cooling?

Did I forget 2 stroke and air cooled?

[FW17]

[Rodak]

There is so much that was not explored because of restrictions. I am thinking variable valve timing could have allowed pseudo Atkinson cycle operation to aid fuel efficiency in race stints. Things like variable intake runners.. Variable valve lift...

Yeah, there could have been some interesting things happen. Banning rotary valves always seemed odd to me. By the way, current F1 engines do have variable inlet runners.... I think; too lazy to check.

viewtopic.php?t=3045

[saviour stivala]

Yes. the present PU does have variable intake runners as did the NA 3-LITRE V10. But variable valve timing was not and is still not permitted.

[gruntguru]

Variable intake was introduced a few years ago. Haven't heard of that rule being wound back.

VVT is an obvious omission. Just about everything on the road these days has it. Cam phasers are mature technology and very reliable. . . and obviously very relevant.

(Not often used in race engines due to high compression, tight clearance volume - limiting the range of VVT. But if the engine designers can use it to advantage, why not let them?)

Banning rotary valves was a shocker. Particularly the way it was done - at a point when someone had gone a long way down the development track of a F1 rotary valve engine.

[FW17]

Why rotary valve has not seen use in prototype racing or in the real world?