Ferrari Power Unit Hardware & Software

[saviour stivala]

The best of the NA engines with around 19mm valve lift and most of the combustion chamber formed by the necessity of the 4 valve pockets inside the piston were struggling to get past 12:1 compression ratio.
The more the maximum combustion power the more the need for reliability, better fuel consumption and better harvesting when said maximum combustion power mode is used during the race. When used during qualifying those said three things are not as critical.

[Dr. Acula]

I am more leaning towards Ferrari has a disgustingly powerful combustion process that is so damaging to engine life that they only use it when necessary. If there are limits on compression ratio, they are probably very close to it.

The rules limit the compression ration to 18:1 which is insanely high already for a natural aspirated petrol engine, let alone a heavely turbo charged one.
...

But not exceptionally high for a direct injection engine. Most Diesel engines are using in excess of 18:1. Of course you can get away with such a high compression when the fuel burns slower, hence limiting the temperatures. And it is also well known that higher compression improves efficiency. Even the old V8 in F1 used compression ratios of about 16:1 (only limited due to the short stroke used)

That doesn't matter much. Did we see a significant jump in compression ratio when direct injection was introduced in petrol roadcar engines? No we didn't. Comparing Diesel and Petrol is like comparing Apple and Oranges.

The rules in F1 doesn't allow HCCI. That's why they run a TJI setup. But even with TJI, the fuel needs time to mix properly with the air in the cylinder otherwise it will not burn down properly and basically you would waste fuel, something you have to prevent under the current regulations.
This means you have to start to inject fuel quite early, long before the piston reaches TDC.
The thing that allows this high compression ratios in F1 is actually the fact that the overall mixture in the cylinder in very very lean.

Actually this is also a problem in direct injected petrol road cars under partial load. Because the cylinder aren't filled that well with air under partial load, the fuel has problems to mix properly and this creates a lot of particulate matter if burned. What they do in road cars now is actually to add a port injection system which only injects fuel under partial load and alows a cleaner combustion this way.

[saviour stivala]

In my opinion the TJI combustion system is not compatible with formula 1 direct injection rules, not even when inverted on its side to meet exhaust side entry injection because it still injects and ignites in a pre-combustion chamber.

[ringo]

I believe we did see a jump in compression ratio with the direct injected road cars.
Take the 911 turbo for instance that went from 9:1 compression ratio to 9.8:1 when it was changed to direct injection in 2009.
The increased CR is not solely responsible for the power improvement, (460hp to 530hp), as the displacement increased, but there was a night and day difference with power and also fuel economy.
The race cars are also not limited by emissions, so they will further exploit compression ratio. On the other hand increased boost pressures also accomplishes the same thing, so there is a balance between turbo boost and compression ratio. The real lynch pin for all of this is the fuel chemistry and how much allowance it has for temperature and compression.

From basic calculations i suspect compression ratio is in the 14.5:1 range currently with these engines. Correct me if i am wrong.

[subcritical71]

Regarding bleeding air into the turbine from the compressor, i don't think that would be very helpful and doesn't have anything to do with acceleration since the MGUK can only output 120kW.
It is possible to get more power from the turbine by dropping the pressure at its outlet, and in turn harvest more or increase boost pressure, but why dump boost to make boost?

Here's how I think the bleeding air from the compressor could work. Just to note, I don't think they are doing it for a power advantage but more for an aerodynamic advantage. Having a low speed aero advantage would allow greater acceleration and therefore maximize its benefit on the straight. Let me explain.

High level lets break down its usage into 3 phases.

• Phase 1: From standstill to a point when no longer traction limited

• Phase 2: Coming out of slow speed corner until no longer traction limited

• Phase 3: No longer traction limited

During phase 1, the MGU-K is unable to be used until 100kph. From the start my idea would be that the turbo is spooled up electrically and producing more air than the engine demands. This excess are is routed to the exhaust where it mixes with the normal exhaust gases. When the combined exhaust gases exit the tailpipe it aids in the rear wing efficiency and adds downforce. This would allow greater power to be applied at the critical first moments of the race. When the speed is over 100kph the MGU-K can be brought in. The MGU-K can add enough power to keep the rear wheels from loosing traction until it hits 120kW or when you are no longer traction limited. After this the teams normal deployment/harvest strategy can be assumed since you already have made the early acceleration advantage.

During phase 2, this is essentially phase 1 but being able to use the MGU-K immediately. Also limiting its output in order to prevent wheel spin.

Phase 3, normal strategies apply.

[godlameroso]

In my opinion the TJI combustion system is not compatible with formula 1 direct injection rules, not even when inverted on its side to meet exhaust side entry injection because it still injects and ignites in a pre-combustion chamber.

Are you familiar with spark plug non-foulers?

[63l8qrrfy6]

In my opinion the TJI combustion system is not compatible with formula 1 direct injection rules, not even when inverted on its side to meet exhaust side entry injection because it still injects and ignites in a pre-combustion chamber.

Since TJI is a Mahle system an they are a big Ferrari partner would you say that the Ferrari combustion system is illegal ?

[saviour stivala]

In my opinion the TJI combustion system is not compatible with formula 1 direct injection rules, not even when inverted on its side to meet exhaust side entry injection because it still injects and ignites in a pre-combustion chamber.

Are you familiar with spark plug non-foulers?

Yes I am, in fact in the height of their popularity (side-valve/flat-head) era I use to make them on my lathe for others to save them having to re-bore their engine, that was a time when a re-bore was regarded as a swear word.

[saviour stivala]

Malhe TJI combustion system is not compatible with the FIA direct injection rules. Because it injects and ignites in a pre-combustion chamber.
Because Malhe is a FERRARI partner it doesn’t mean FERRARI are using Malhe TJI combustion system.

[Dr. Acula]

Malhe TJI combustion system is not compatible with the FIA direct injection rules. Because it injects and ignites in a pre-combustion chamber.
Because Malhe is a FERRARI partner it doesn’t mean FERRARI are using Malhe TJI combustion system.

Sorry, but:

5.10.2 There may only be one fuel injector per cylinder and no fuel injectors are permitted upstream of the intake valves or downstream of the exhaust valves. Only approved parts may be used and the list of parts approved by the FIA, and the approval procedure, may be found in the Appendix to the Technical Regulations.

doesn't prohibit a TJI system like the one from Mahle at all. "Direct Injection" isn't even particularly stated in the rules. The fuel injection must happen somewhere between the inlet and exhaust valves, that's all the FIA wants.

But one funny thing, what does the FIA actually refer to with the term "fuel injector"? The nozzle or the whole part with electrical connections and everything? Because if they mean the whole part, you can use one "fuel injector" with multiple nozzles.

[gruntguru]

There has been lots of discussion of this here in various threads. The intent and benefits of TJI could be achieved by a single direct injector spraying towards the exterior of the prechamber (containing the spark plug). Early injection will create the homogeneous lean mixture throughout. A brief injection during the compression stroke will add extra fuel to the lean mixture which is transferring into the prechamber during this period. The result would be rich mixture in the prechamber and lean mixture in the main chamber.

[saviour stivala]

“there has been lots of discussion of this (Malhe TJI combustion system) here in various threads”. Yes there was, and also elsewhere where the speculation started about what the formula one engine combustion chamber is like and or the process is like.
“the intents and benefits of ‘TJI’ could be achieved by a single direct injector spraying towards the exterior of the ‘prechamber’ (containg the spark-plug)” so the formula one engine uses a ‘pre-combustion chamber’. That is the original rubber band like reasoning to justify his claims, by the original discoverer of what goes on inside the FI engine combustion and or what the combustion chamber is like. This after the original discoverer inside a week's time had changed his mind from manufacturers (are using HCCI) to manufacturers (are using Malhe TJI).

[godlameroso]

“there has been lots of discussion of this (Malhe TJI combustion system) here in various threads”. Yes there was, and also elsewhere where the speculation started about what the formula one engine combustion chamber is like and or the process is like.
“the intents and benefits of ‘TJI’ could be achieved by a single direct injector spraying towards the exterior of the ‘prechamber’ (containg the spark-plug)” so the formula one engine uses a ‘pre-combustion chamber’. That is the original rubber band like reasoning to justify his claims, by the original discoverer of what goes on inside the FI engine combustion and or what the combustion chamber is like. This after the original discoverer inside a week's time had changed his mind from manufacturers (are using HCCI) to manufacturers (are using Malhe TJI).

So is this a hint that the combustion process is conventional?

[subcritical71]

So is this a hint that the combustion process is conventional?

For some very old history....
https://www.motorsportmagazine.com/opin ... t-ignition

[Tommy Cookers]

history that states the F1 fuel is octane limited as road fuel

so in 2016 they were running on 2013-rule fuel not 2014 or 2015 or 2016-rule fuel