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Is the pressure ratio biased towards the compressor or turbine. When you say 30%, does that mean the PR is 30% higher on the compressor side or the turbine side? Sorry I realize now it's a silly question.

http://www.f1analisitecnica.com/2016/02 ... a-nei.html" target="_blank

2015 ICE and turbocharger + 2016 MGU-K, MGU-H and ES for the first test session.

Makes a lot of sense to use known good parts at the first test to help evaluate the new MGU units and energy store. They should get solid information to compare with last years figures before bolting in the new ICE which would add an extra unknown variable if used at first

Joseki wrote:http://www.f1analisitecnica.com/2016/02 ... a-nei.html" target="_blank" target="_blank

2015 ICE and turbocharger + 2016 MGU-K, MGU-H and ES for the first test session.

Source must be from Italy?

They're using the 2015 engine but 2016 ERS+turbo. To me this means they managed to keep all the components the same size, hopefully they improved their respective outputs enough.

I think Monday will see the complete new unit.

Joseki wrote:http://www.f1analisitecnica.com/2016/02 ... a-nei.html" target="_blank" target="_blank

2015 ICE and turbocharger + 2016 MGU-K, MGU-H and ES for the first test session.

How can this be true...Wazari said number of times 2016 ICE is their strongest point of development this winter.
I hope this is false if not,if for some reason complete 2016 PU is not ready, it would be quite embaressing for Honda.

Honda play down recent rumors.

http://www.pitpass.com/55489/Honda-play ... ity-claims

GoranF1 wrote:Honda play down recent rumors.

http://www.pitpass.com/55489/Honda-play ... ity-claims" target="_blank

I feel that if the plan was to ruin the 2015 engine with 2016 ERS he would have said so, why not?

I would say McLaren have never been the most open team and in this regard I'm sure Ron would prefer to roll back the clock to before when Red Bull got involved and made the sport 'more open'.

pgfpro wrote:

PlatinumZealot wrote:

pgfpro wrote: From my own experience the compressor PR and turbine PR don't always run close PR numbers. Depending on rpm, boost there can be as much as a 30% difference.

My DD turbo Talon, compressor PR verse turbine PR is
30% PR difference @ 4500 rpm@25 lbs.
12% PR difference @ 5500rpm@28lbs.
9% PR difference @ 6500rpm@28lbs.
0% PR difference @ 7500rpm@28lbs.
9% PR difference @ 8500rpm@28lbs.
Now on this setup its kinda a hybrid turbo, but even when I match the compressor size more to the turbine size the numbers on my turbo simulator show a higher PR % difference.

I have a lot more examples from customer cars with data logs showing more of the same.

Did you have four pressure sensors? Inlet and entry for both compressor and turbine? Or was it all compared to atmospheric pressure... remember the losses in the intake and exhaust pipe is significant so you might get different numbers. But anyway I do agree that the PR can be different.

Actually nine sensors. Two compressors inlet and outlet. Two turbine inlet and outlet. One wheel speed sensor on the compressor side. I did this for data reasons when I was running my stage compound system. The example above is now just my single turbo system with five sensors.

Most radial turbo manufacturers well tell you anything past 40% PR difference on either side of 0 will be a poor compressor turbine match.

OK good info.

As far as the MGU-H unit, I think it has been discussed at length as to the lack of performance from this unit last year. I think it's a combination of the lack of turbine output and the matching of turbine, compressor and MGU-H unit. As others have mentioned, it's like a puzzle where all the pieces need to fit nicely for this technology to work at desired efficiency. Obviously Honda missed the mark in this area and hopefully learned from their mistakes. I think they have. How well they have corrected this issues remain to be seen but again from my understanding, dyno results have been good.

I have not heard about using the 2015 ICE + 2016 spec ERS for testing, although I wouldn't be surprised if they did in the initial testing days along side the 2016 ICE to get relative benchmarks for all the components. Again, it's the media and who do you believe? I have not heard anything new with regards to testing or "reliability" issues except for minor concerns.

ringo wrote:

gruntguru wrote:

Per wrote:You really need to treat the compressor and turbine as two separate components when you discuss their sizing. The only thing they have in common is their RPM.

. . . . and the massflow. Turbine massflow is always equal to compressor massflow plus fuel flow (about 4 or 5% extra)
. . . . and the pressure ratio. Turbine PR cannot be a lot different to compressor PR.

Exhaust flow, pressure ratio and temperature dictate the turbine size.

You are probably thinking a proper gas turbine that has constant pressure combustion.

Not at all.

I am thinking firstly about the piston engine and what pressure you can apply to the intake and the exhaust. Running the exhaust pressure significantly higher than the intake creates:
- loss of crankshaft power due to pumping work
- loss of crankshaft power due to poor scavenge and charge dilution
- detonation
- durability issue due to higher temperature

Secondly - thinking about the turbine, you do not want to run the exhaust pressure significantly lower than the intake (certainly not 30% lower PR as in pgfpro's example) because you are throwing away energy that could be recovered by the turbine. For a normal turbocharged application, lower is better. There is no opportunity to recover exhaust energy beyond what is needed to drive the compressor but the piston engine will benefit from any reduction in BP.

Ok i see now that you have elaborated on it.
I guess the valve timing is also important as you mentioned scavenge.