[WEC] Rebellion Racing

[TF110]

I knew you meant that, sorry. I guess I was just rehashing the scenario they face. Maybe they can bring the weight down by next season. At least the engine makes good power.

[Mike E]

Via Mat Fernandez:
Rebellion considering options for another engine in 15 - current V8 not offering more power despite higher energy alloc. (Source:@autohebdo)

Guess they are looking at that AER.

[TF110]

Could talk to Toyota about their turbo 4 ran in Super GT and Super Formula. Will be interesting to see what they do. Matt Hernandez also mentions Charles Pic as talking with the team in Bahrain.

[Juntos]

Toyota is giving Rebellion nothing but bills. AER seems a much better choice at the moment.

[carbon_titanium]

surely oreca will have to modify tub and subframes to fit the AER in the car. Anyway this possible switch is a smart move; the 3.4 V8 torque release is ridiculous compared to the other engines.

[Deleted]

Hopefully something else as I don't want the privateer sub cat becoming all-AER spec class, seeing as the prospect of new teams is quickly vanishing (again...) for next year.

Weren't Judd, Zytek, HPD and maybe even Audi the other options being (in consideration to be) developed for this year's P1 market already?

[JoestForEver]

Originally Posted by Chiana

Hopefully something else as I don't want the privateer sub cat becoming all-AER spec class, seeing as the prospect of new teams is quickly vanishing (again...) for next year.

Weren't Judd, Zytek, HPD and maybe even Audi the other options being (in consideration to be) developed for this year's P1 market already?

The Zytek 2.2l turbo comes with a ERS system used by GT500 NSX. As for Judd, I couldn't recall any news about that?

[Deleted]

Originally Posted by JoestForEver

The Zytek 2.2l turbo comes with a ERS system used by GT500 NSX. As for Judd, I couldn't recall any news about that?

http://www.engdev.com/new-lmp1-engine-for-2014/

Of course, that is 13 months old now

[TF110]

Have a read on Rebellion's twitter of the ongoing discussion. Theyre not complaining so much about the engine. Theyre speaking of the way the hybrid cars accelerate. They also speak of 'capacity' being an issue. Sounds to me they dont want a bigger, heavier engine. Maybe theyd like to have a small hybrid unit but still be able to run at a light weight?

[Deleted]

So Rebellion has great top speed, but crap acceleration and likely cornering in comparison to works cars.

In one of the earlier press releases they said they strictly said no to hybrid because of much higher costs and the fact that it would make them lose the race-by-race BoP adjustments / aided values.

If they implemented hybrid after all and went to 2MJ (or even 1MJ if ACO was to allow that), they'd have to beg FIA and ACO to change the regs so that the performance balancing wouldn't be hybrids against non-hybrids, but factories vs privateers of the past. The H/L subcategorization, at least in official form, is soon gonna be obsolete anyway

Of course, then you could have private teams with hybrids & non-hybrids receiving same BoP breaks against factories, which could leave to moanings...

[TF110]

No engine they buy will match the instant torque and power of the electric motors. Theyll have to run something like those v12 diesels.

[carbon_titanium]

Originally Posted by TF110

No engine they buy will match the instant torque and power of the electric motors. Theyll have to run something like those v12 diesels.

The actual 3.4 should not develope more than 450Nm in theory (the same engine used in SC430 GT500 had a torque peak close to 400Nm); the AER engine is twin turbo, so at least we could expect 650Nm. With a comparable power output, it is a great torque boost. Acceleration will improve a lot.
Problem is that the engine will make the car much more heavier and unbalanced on rear.

[TF110]

They are not the same engine. They share a common architecture, but theyre not the same 'RV8'.

[chernaudi]

Even the 3.7 Toyota factory spec engine (based on the 3.4) makes more torque on it's own--not much, but more torque is more torque.

The problem is that for Rebellion to get the torque to accelerate the way that they want, they either need some form of hybrid system, a forced induction engine (be it turbocharger or pressure-wave supercharger--that a technology that I'm surprised that no one has tried out yet), or a huge capacity engine, probably 5-5.5 liters, with 5.5 being the theoretical maximum for privateer-spec engines or stock block engines for private teams.

There's decent enough stock block engines out there from a power-end of things: the GM LS is a sound choice, and Ford still have the 5.0 Cammer DP engine on offer, the newer Coyote engine used in the Mustang GT and V8 F-150 trucks, or the new 5.2 liter flatplane crank GT350 engine used in the upcoming Shelby GT350 Mustang.

But the problem is that they are still stock block engines, and I don't know if Rebellion or anyone else could get much in the way of BOP breaks for that, even when you consider that the 5.2 GT350 engine stock makes over 500bhp, which is more than Toyota claim for their 3.7 V8, and with more torque in race spec.

It's about what do you gain, and what do you lose. Hell, Zytek and Judd have 4.4/4.5 liter versions of their old LMP2/LMP1 engines for sale, but they're not selling.

One thing that I do see across the board--including private teams--is a probably shift to forced induction engines, mostly turbo engines, which are powerful, have lots of torque, and are fuel efficient.

Maybe in due time Toyota will dig out the old 2.1 liter IMSA GTP engine in an updated form and offer it to customers, and even use it or a development of it in the TS050?

[TF110]

They understate the engine power. The THS-R is claimed 520ps engine (not under 500hp) and 480ps hybrid. I dont doubt the Rebellion engine makes 550-600hp, but its a customer engine. If Toyota make a new customer engine itll be based off the GT500/Super Formula.

[carbon_titanium]

To me is really unlikely to think about 550-600hp for the rebellion engine... true is they have a huge fuel flow break but to me at best around 540hp is the power output. I say this because the r-one basicly hasn't a real high downforce package yet, so with a LD design + 600hp at le mans the r-one had to mark top speed close or over 340km/h.
Anyway I know that the RV8K of rebellion isn't exactly the same engine used in super GT, that's the reason why I think that the rebellion engine has more torque using the same displacement.

an interesting engine for lmp1-L could be the GM 5.5 used in the corvette DP, updated with DI. Usually corvette DP consumes 76L in around 45 minutes, with DI the mandatory LMP1-L 73L can last more than 50 minutes!
the engine developes a lot of torque (more than 600Nm) and being an LS small block it should not be so heavy!

[MyNameIsNigel]

In this interview by endurance-info.com, Mathias Beche claims that the Toyota engine currently used by Rebellion would produce a power output of (only) 520 HP.

Based on the current max fuel flow rate for LMP1-Ls (i.e. 104.9 kg/h) and assuming a BSFC target of the order of 220 g/kWh, that should in theory lead to a peak power output of approx. 475-480 kW, i.e. a power figure closer to 650 HP.

Now, it could be that the Toyota engine used by Rebellion cannot achieve the aforementioned BSFC target.

If the power deficit is so huge, that should lead Rebellion to contemplate using a different engine in the future.

[carbon_titanium]

Unrestricted and without fuel flows surely the old rv8k can reach 600hp, but to respect mandatory fuel flows values somehow the engine is detuned. 520Hp is a realistic value, less than expected but realistic.
The R-one needs a huge aero configuration development first of all and then an engine with much more torque... or nothing at all if they will just keep on fighting only against the kolles fake lotus...

[silente]

If the quote (520 hp) is true, it is not surprising they are not so much faster than p2 cars...This is just a bit better than a normal p2 engine...

[TF110]

If only 520hp is being made then theyre top speed is amazing for such a low amount. Sounds like a driver is underrating the engine like he's supposed to.

[PorscheFanNo1]

Originally Posted by TF110

If only 520hp is being made then theyre top speed is amazing for such a low amount. Sounds like a driver is underrating the engine like he's supposed to.

An aerodynamicly inefficient car is usually quick in a straight line, cause it has too low downforce figures, and low drag as a result.
Also, the hybrid's only go on full power at the beginning of the straights, the last 300 meters they are just going like a quarter throttle to maintain the speed while consuming the least amount of fuel. So the hybrids this year has usually had low topspeed numbers, while the non hybrids have been full throttle longer, cause they have less toys to play around with for optimal fuel usage over a lap.

[TF110]

That doesnt explain away their top speed being right there in qualifying, where coasting is less of a factor. Mostly the speed traps aren't at the end of the straight anyway. A car like Porsche or Toyota probably has less drag than the Rebellion, and more downforce. Its the hybrid power thats the biggest difference. Instant power and torque is something they cant match.

[GTRMagic]

Originally Posted by silente

If the quote (520 hp) is true, it is not surprising they are not so much faster than p2 cars...This is just a bit better than a normal p2 engine...

Why not an engine from a Panoz.. or similar... they seemed to last all day, and should be good for over 650bhp... and sound 'right'

[Mike E]

Tweet from Mat Fernandez:

"New source (@autosprint) echoing Rebellion's quest for another engine. Article mentions talks with AER, Judd and, most surprising, Cosworth!
"

[MyNameIsNigel]

According to German SportAuto magazine, Toyota have reportedly announced at Sao Paulo that they will stop supplying engines to customer LMP1 teams starting from next year. This evidently and directly impacts Rebellion Racing. The AER engine is identified as a likely replacement.