Thanks for sharing this clip. Certainly interesting to ponder.Holm86 wrote:
Its being explained pretty well in this clip. Look from around 2.15 mins in.
Thanks for sharing this clip. Certainly interesting to ponder.Holm86 wrote:
Its being explained pretty well in this clip. Look from around 2.15 mins in.
Curious as to what mapping experience you have a high boost turbo engines :s Boost makes a massive difference to torque and likewise where that boost occurs will have a significant impact on the power curve.321apex wrote:In essence what you are saying in practical terms is not true. Please read carefully what I wrote - we are speaking of "location" along the RPM axis where power or torque peaks occur.Abarth wrote:
What????? Variation in cam timing and/or valve lift profile do exactly what boost variation does, it allows more or less combustion air at a given operating point.
If you can control boost via software (which is standard these days) you can shape torque (and therefore power) curves very arbitrarily, of course within the constraints of engine robustness, allowed fuel flow or other driveability demands (i.e. response, especially at low revs, etc)
Holding inlet and exhaust geometry as a constant, the cam timing has the overwhelming impact in determining these RPM areas. Boost only move it up or down in "general vicinity" of those areas. The higher you dial in the boost, there is even a tendency to move the locations of those peaks LOWER. As an example in low boost mode of a given engine you may see a power peak at 10000 rpm, and at the maximum possible "safe" boost limit you may make tons more power but the peak may slide down to 9700 RPM.
Do you follow?
IMHO of course.
and the power curve probably very flat since it is not limited by what the engine could make, but limited by what you can get through the restrictormrluke wrote:Curious as to what mapping experience you have a high boost turbo engines :s Boost makes a massive difference to torque and likewise where that boost occurs will have a significant impact on the power curve.321apex wrote:In essence what you are saying in practical terms is not true. Please read carefully what I wrote - we are speaking of "location" along the RPM axis where power or torque peaks occur.Abarth wrote:
What????? Variation in cam timing and/or valve lift profile do exactly what boost variation does, it allows more or less combustion air at a given operating point.
If you can control boost via software (which is standard these days) you can shape torque (and therefore power) curves very arbitrarily, of course within the constraints of engine robustness, allowed fuel flow or other driveability demands (i.e. response, especially at low revs, etc)
Holding inlet and exhaust geometry as a constant, the cam timing has the overwhelming impact in determining these RPM areas. Boost only move it up or down in "general vicinity" of those areas. The higher you dial in the boost, there is even a tendency to move the locations of those peaks LOWER. As an example in low boost mode of a given engine you may see a power peak at 10000 rpm, and at the maximum possible "safe" boost limit you may make tons more power but the peak may slide down to 9700 RPM.
Do you follow?
IMHO of course.
For example, by running WRC Style anti lag you can achieve max power in an rpm range that usually would not be sufficient to spool the turbo.
Do you both mean an application restricted with an orifice in the air inlet?langwadt wrote:Curious as to what mapping experience you have a high boost turbo engines :s Boost makes a massive difference to torque and likewise where that boost occurs will have a significant impact on the power curve.mrluke wrote:
In essence what you are saying in practical terms is not true. Please read carefully what I wrote - we are speaking of "location" along the RPM axis where power or torque peaks occur.
Holding inlet and exhaust geometry as a constant, the cam timing has the overwhelming impact in determining these RPM areas. Boost only move it up or down in "general vicinity" of those areas. The higher you dial in the boost, there is even a tendency to move the locations of those peaks LOWER. As an example in low boost mode of a given engine you may see a power peak at 10000 rpm, and at the maximum possible "safe" boost limit you may make tons more power but the peak may slide down to 9700 RPM.
Do you follow?
IMHO of course.
For example, by running WRC Style anti lag you can achieve max power in an rpm range that usually would not be sufficient to spool the turbo.
and the power curve probably very flat since it is not limited by what the engine could make, but limited by what you can get through the restrictor
321apex wrote:Do you both mean an application restricted with an orifice in the air inlet?langwadt wrote:Curious as to what mapping experience you have a high boost turbo engines :s Boost makes a massive difference to torque and likewise where that boost occurs will have a significant impact on the power curve.mrluke wrote:
In essence what you are saying in practical terms is not true. Please read carefully what I wrote - we are speaking of "location" along the RPM axis where power or torque peaks occur.
Holding inlet and exhaust geometry as a constant, the cam timing has the overwhelming impact in determining these RPM areas. Boost only move it up or down in "general vicinity" of those areas. The higher you dial in the boost, there is even a tendency to move the locations of those peaks LOWER. As an example in low boost mode of a given engine you may see a power peak at 10000 rpm, and at the maximum possible "safe" boost limit you may make tons more power but the peak may slide down to 9700 RPM.
Do you follow?
IMHO of course.
For example, by running WRC Style anti lag you can achieve max power in an rpm range that usually would not be sufficient to spool the turbo.
and the power curve probably very flat since it is not limited by what the engine could make, but limited by what you can get through the restrictor
This is what I found googling:tuj wrote:Supposedly Renault is talking with/seeking outside experts to help them with what appear to be structural issues with their engine. From what I understand, they have never done this before, always wanting to preserve their technology. Makes you wonder who they are talking to? Cosworth? And now there is already a rumor about RBR wanting to switch powerplants for 2015.....
Until today I have not thought that such problems could exist. But you have to take it a bit more serious if Minardi is the source.Minardi wrote:According to circulating information, the situation seems more difficult than that and not easy to solve. It seems that Red Bull are exploring a possible change of engine for 2015. I have heard that Renault, struggling to solve the obvious problems with its turbo V6 'power unit', has gone beyond the walls of its Viry factory and is now "shopping" around for technical fixes. That has practically never happened before as, quite rightly, Renault has always sought to preserve its technology. This news can only feed suspicions of structural problems in the engine that are not easy to solve in the short term.
Isn't that a little over the top. The Lotus F1 shakedown went fine according to Renault en LotusF1. Renault definitely has enough in house expertise about the ICE and Turbo, maybe the electronic part they might lack some knowledge. I know that Ferrari and Mercedes both started a separate hybrid technologies unit in their engine department. Both hired a lot of engineers with electrical engineering backgrounds. RBR has a contract until 2018 or 2019 with Renault as their works partner I don't think they will abandon that. But Viry worked with smallest budget and the smallest work force, so maybe it isn't a surprise that they are lacking behind?tuj wrote:Supposedly Renault is talking with/seeking outside experts to help them with what appear to be structural issues with their engine. From what I understand, they have never done this before, always wanting to preserve their technology. Makes you wonder who they are talking to? Cosworth? And now there is already a rumor about RBR wanting to switch powerplants for 2015.....
The title of that article is... better concentrate on the content of that article.Kiril Varbanov wrote:To be honest, I find Renault issues rumors exaggerated. Engine manufacturer with such resources and experience cannot be in the dark.
Still, the headlines say: Renault could ask for reliability break once F1 season is underway - http://www.autosport.com/news/report.php/id/112519
According to their public face, yes. From what I heard, the shakedown actually went in fits and starts, with the car stopping numerous times for software or hardware fixes. Now some of that is to be expected, but if Renault believes their engines can only run 250km, that's a major problem that they might not have time to fix. We'll have to wait for Bahrain, but my prediction is that none of the Renault teams will do more than 250km on a single powerplant.The Lotus F1 shakedown went fine according to Renault en LotusF1
langwadt wrote: yes WRC runs a 34mm air restrictor on the inlet, limiting the power to 300 something or there about
F1 runs a 100kg/h fuel restriction limiting the power to 500-600 depending on how they can use it
in both cases it has the effect of cutting the top of the normally peaky power curve of a highly tuned engine
making it mostly flat in the range where an unrestricted engine could have made more power but is limited
by the fuel or air limit
Sorry! What the abbreviation FMEA stads for?Abarth wrote:I
OTOH, back when I was involved in design and project management and were doing FMEA, I always said that we will never have enough fantasy to figure out all troubles ahead.
And I was always proven right, unfortunately...
Why would they hide the ''fact'' that the Lotus shakedown didnt go well and then admit that the STR shakedown didnt go well?tuj wrote:According to their public face, yes. From what I heard, the shakedown actually went in fits and starts, with the car stopping numerous times for software or hardware fixes. Now some of that is to be expected, but if Renault believes their engines can only run 250km, that's a major problem that they might not have time to fix. We'll have to wait for Bahrain, but my prediction is that none of the Renault teams will do more than 250km on a single powerplant.The Lotus F1 shakedown went fine according to Renault en LotusF1