F1technical.net

FW17 wrote:http://i66.tinypic.com/2dvifef.jpg


Looks like the variable length trumpet has incredibly short range in comparison to the other 3 engines

please someone clarify this for me, I can't understand why they use variable length trumpet, I thought that variable trumpet is useless for forced induction engines and I've also read in one of ferrari forums that ferrari has dropped them for 2016.

amho wrote:

FW17 wrote:http://i66.tinypic.com/2dvifef.jpg


Looks like the variable length trumpet has incredibly short range in comparison to the other 3 engines

please someone clarify this for me, I can't understand why they use variable length trumpet, I thought that variable trumpet is useless for forced induction engines and I've also read in one of ferrari forums that ferrari has dropped them for 2016.

Ferrari didn't have them before 2016.

amho wrote:

FW17 wrote:http://i66.tinypic.com/2dvifef.jpg


Looks like the variable length trumpet has incredibly short range in comparison to the other 3 engines

please someone clarify this for me, I can't understand why they use variable length trumpet, I thought that variable trumpet is useless for forced induction engines and I've also read in one of ferrari forums that ferrari has dropped them for 2016.

Why would it be useless? The operating principle of the ICE does not change by the addition of pressurised air from the outside. Pulse tuning on the intake tract still applies.

I think you have got Ferrari mixed up. Last season and the season before that Ferrari did not have variable trumpets due to not being enough space with the liquid to air inter cooler being in the V. Now that they have moved the intercooler out of the V, it is my understanding that they are currently using a L/A intercooler.

amho wrote:[.....]please someone clarify this for me, I can't understand why they use variable length trumpet, I thought that variable trumpet is useless for forced induction engines and I've also read in one of ferrari forums that ferrari has dropped them for 2016.

In this case it would not be to increase the charge-air flow as in an N/A engine, but ultimately to reduce charge-cycle work.
I'ts all about efficiency, albeit the gains will not be tremendous I think. These engines are running in a pretty narrow rpm range anyway....would be interesting to see how much efficiency improvement the variable length trumpets allow.

Abarth wrote:

amho wrote:[.....]please someone clarify this for me, I can't understand why they use variable length trumpet, I thought that variable trumpet is useless for forced induction engines and I've also read in one of ferrari forums that ferrari has dropped them for 2016.

In this case it would not be to increase the charge-air flow as in an N/A engine, but ultimately to reduce charge-cycle work.
I'ts all about efficiency, albeit the gains will not be tremendous I think. These engines are running in a pretty narrow rpm range anyway....would be interesting to see how much efficiency improvement the variable length trumpets allow.

'suppose it's a drivability thing. Perhaps it increases the usable RPM range by 10-20% or so.

Hasegawa quote in f1-sokuho magazine (print/e-book media):


estimating the gap to Mercedes to be about 50-60 hp
we havent even reached our set target yet, but of course we are able to see the path to achieving the target

hurril wrote:

Abarth wrote:

amho wrote:[.....]please someone clarify this for me, I can't understand why they use variable length trumpet, I thought that variable trumpet is useless for forced induction engines and I've also read in one of ferrari forums that ferrari has dropped them for 2016.

In this case it would not be to increase the charge-air flow as in an N/A engine, but ultimately to reduce charge-cycle work.
I'ts all about efficiency, albeit the gains will not be tremendous I think. These engines are running in a pretty narrow rpm range anyway....would be interesting to see how much efficiency improvement the variable length trumpets allow.

'suppose it's a drivability thing. Perhaps it increases the usable RPM range by 10-20% or so.

It will also increase the power in the range they currently use (except at the rpm where the previous fixed trumpet length was optimal)

What is the power band in these engines ~6,000 - 12,800 rpm? That's a pretty wide powerband, even from 8,000 - 12,800, that's still 4,800 rpm, which is a bit wider than the V8 power band of ~4,000 rpm.

godlameroso wrote:What is the power band in these engines ~6,000 - 12,800 rpm? That's a pretty wide powerband, even from 8,000 - 12,800, that's still 4,800 rpm, which is a bit wider than the V8 power band of ~4,000 rpm.

V8s had no power band to speak of compared to V6T. Rev drop between gears was about 2.000 for most tracks, and low power band was the reason cars were always in the rev limiters.

As of 2014, power band is not an issue at all. 2014 gear ratio differences had negligible effect on the overall speed of the cars, no matter how wide or close they were.

So with Alonso out, if this PU gets destroyed, (hoping it doesn't of course), will the next PU be his third of the season??

Thunder18 wrote:So with Alonso out, if this PU gets destroyed, (hoping it doesn't of course), will the next PU be his third of the season??

Yes. The driver will not affect.

I would think about the possibility to take the unlimited amount of PU's exploit then. This way you allow the reserve driver to have a clean start.

amho wrote:

FW17 wrote:http://i66.tinypic.com/2dvifef.jpg


Looks like the variable length trumpet has incredibly short range in comparison to the other 3 engines

please someone clarify this for me, I can't understand why they use variable length trumpet, I thought that variable trumpet is useless for forced induction engines and I've also read in one of ferrari forums that ferrari has dropped them for 2016.

For turbo street cars, mostly, no major difference given the complication.

Ok edit. Some street cars come with two stage intake manifolds - in both metal or plastic. Some are continuous scrolls - usually plastic. For the variable manifolds, besides the strength and dimensional stablility (for plastic) concerns under the heat and pressure of boost, the tightness of the seals over time is another question. So this extra design, precision, complexity and cost, might explain why variable intakes weren't adopted for turbocharged vehicles... my 2 cents

Variable intake has a small effect - perhaps equivalent to 0.5 psi of boost.

What effect could it have on comustion?

*Perhaps allowing a flatter torque curve is beneficial for MGU-H generator mode.