Any theories on the strange McLaren-Mercedes exhaust note?

[Jag_Warrior]

Something related to the blown diffuser probably... but what could it be?

[Zico]

Im thinking something along the lines of an ALS type of throttling while off the throttle to reduce the on-off effect on the blown diffuser to reduce twitchyness at the expense of increased rear brake bias for compensation?

[steveaki13]

I am not clever enough to add anything to this discussion. :dozey:

So I really shouldn't have posted here.... Sorry. :s mokin:

[wedge]

Something related to the blown diffuser probably... but what could it be?

Doubt it though I could be wrong. McLaren has the contemporary design. Another team has there's directed more at the floor rather than into the diffuser.

[Zico]

Doubt it though I could be wrong. McLaren has the contemporary design. Another team has there's directed more at the floor rather than into the diffuser.

I think it was Martin Brundle iirc who comented on the strange exhaust being something to do with the blown diffuser, had me wondering how it might work also.

[555-04Q2]

Exhaust note? They must be cheating!

[ShiftingGears]

Exhaust note? They must be cheating!

Beat me to it! :p :

[SGWilko]

It is entirely possible it is one or both of the following;

Ignition timing on the overrun changed to create more airflow while throttle not 'on load',

or,

Position/outlet aspect/shape of exhausts is causing such strange acoustics.

[Ranger]

I think they may still have asymmetric exhaust outlets. They definitely had it before the blown diffuser modification.

[SGWilko]

I think they may still have asymmetric exhaust outlets. They definitely had it before the blown diffuser modification.

Not quite. The exhaust pipes are same diameter and profile for both banks of the engine, but the cooling outlets in the bodywork from into which the exhausts would exit, where asymetrical, due to differing cooling requirements of water and oil radiators, which reside on opposite sides of the car.

[Zico]

It is entirely possible it is one or both of the following;

Ignition timing on the overrun changed to create more airflow while throttle not 'on load',

or,

Position/outlet aspect/shape of exhausts is causing such strange acoustics.

Yes, it was the note on the overrun that it sounded the most noticable difference

I found this technical PDF that looks at all the F1 Season 2010 - Aerodynamic & Mechanical Updates - Version 3
Updated 7th June 2010 includes blown diffusers, very informative and interesting.

http://www.f1-forecast.com/index.php?option=com_content&view=article&id=112&Itemid=161&lang=en

..though I think we wil have to wait for version 4 to see details of the latest McLaren updates.

[Saint Devote]

This is something that Pat Symonds wrote about in F1 Racing over a month ago. While he was at Renault they worked on it but could not get it to work reliably.

He reckons that Red Bull already have some such system on the RB6 only the engine not change is not as pronounced as on the RB6. There were quite a few in pitlane that noticed the RBR possibility quite a few months ago - hence this is Mclaren following the RBR lead.

I reckon it is a form of traction control but there is a loophole because TC is banned as a controlling of the rear wheels directly - not throttle-ignition.

[Roamy]

they were sucking water off the track and funneling it through the exhaust

[Valve Bounce]

Possibly a resonance inducer for the diffuser.

[SGWilko]

This is something that Pat Symonds wrote about in F1 Racing over a month ago. While he was at Renault they worked on it but could not get it to work reliably.

He reckons that Red Bull already have some such system on the RB6 only the engine not change is not as pronounced as on the RB6. There were quite a few in pitlane that noticed the RBR possibility quite a few months ago - hence this is Mclaren following the RBR lead.

I reckon it is a form of traction control but there is a loophole because TC is banned as a controlling of the rear wheels directly - not throttle-ignition.

We may be at cross purposes here, but I read somewhere - of course, now I want to find it, do you think I can??? - that RBR are using the overrun ignition in qually, but for reliability, as their solution has an impact on engine life, it is not used in the races.

[SGWilko]

Possibly a resonance inducer for the diffuser.

Bit like a flux capacitor? ;)

[Mia 01]

It´s obviously traction control who is forbidded. Cheaters.

Time for Horner to act!

But ofcourse, the ECU is made by MacLaren for all teams.

Clever.

[wedge]

Ignition retardation? That would melt the exhausts unless McLaren found something with the ECU?


http://scarbsf1.wordpress.com/2010/07/10/red-bull-map-q-the-secret-to-the-teams-q3-pace/

Of course this gain doesn’t come for free, the heat of combustion now takes place in the exhaust port, so that the exhaust valve, cylinder head and exhaust pipe all suffer excessive heat. This will affect them, as they cannot withstand this sort of thermal load for long periods. Equally the process burns additional fuel, in the race this is a negative thing as fuel is limited and no refuelling is allowed.

[Mark]

We may be at cross purposes here, but I read somewhere - of course, now I want to find it, do you think I can??? - that RBR are using the overrun ignition in qually, but for reliability, as their solution has an impact on engine life, it is not used in the races.

That would explain their qualifying pace then! And how they can't manage to put it together in the races.

[RJL25]

its just evidence that they are cheating...


to be serious, obviously it's to do with the blown diffuser, they've done something very tricky and far too complicated for us normal people to understand in order to maintain steady exhaust flow when off the throttle.

[ShiftingGears]

Ignition retardation? That would melt the exhausts unless McLaren found something with the ECU?

That was my first thought - surely it's not just what RBR already do for qualifying.

[Mark]

I thought I'd do a bit of googling on this and put in "McLarens exhaust note" and got this thread as the first result!

[Zico]

That would explain their qualifying pace then! And how they can't manage to put it together in the races.

It all makes sense now..

[Sonic]

I thought I'd do a bit of googling on this and put in "McLarens exhaust note" and got this thread as the first result!

Because we are the only ones smart enough to notice ;) LOL!

[Jag_Warrior]

I thought I'd do a bit of googling on this and put in "McLarens exhaust note" and got this thread as the first result!

Hot diggity dog! I made the funny papers! :bounce: :D

It's too bad we can't get Steve Matchett to post here. But I guess he mostly hangs around the SpeedTV board when he does post.