RS4 100 to 300km/h in 25.5 sec.!

[Särås]

Looks like its nice on higways, but i could say that im still going to have orginal size on my Turbos...
/J

[njw123]

Ok, so the MTM K16s are laggy until high revs...

Is there a hybrid turbo option? I thought these had twin vanes. Small ones with little lag low down, and then larger ones for a big kick later...

[dodgydave]

Ok, so the MTM K16s are laggy until high revs...

Is there a hybrid turbo option? I thought these had twin vanes. Small ones with little lag low down, and then larger ones for a big kick later...

No they are bog standard turbos just bigger. If you are talking about the new VTG turbos as found on the new 997 they are way to big to be fitted in the already packed engine back of a RS4. See she bottom picture on here: http://www.turbos.bwauto.com/en/products/vtg.asp

Dave

[flashyg]

My friend has exactly the same issue with these turbos. His car is being dismantled to establish if there is a fault as he has been informed by mtm and dahlback that these turbos spool up well before 4500 rpm!

in the video it did not look like you could reliably say that the car was wide open throttle at the start of the video. To me it looked like he was just holding off. If that is lag then its pretty bad and my friend will be annoyed.

What is this cars HP and can it be reconfirmed that spool up is defo from 5k?
Thanks
G

[S4RS4]

Ok, so the MTM K16s are laggy until high revs...

Is there a hybrid turbo option? I thought these had twin vanes. Small ones with little lag low down, and then larger ones for a big kick later...

No they are bog standard turbos just bigger. If you are talking about the new VTG turbos as found on the new 997 they are way to big to be fitted in the already packed engine back of a RS4. See she bottom picture on here: http://www.turbos.bwauto.com/en/products/vtg.asp

Dave

You are correct in saying they are not VTG but I think you will find these are hybrid turbos and quite different to standard.

[dodgydave]

Ok, so the MTM K16s are laggy until high revs...

Is there a hybrid turbo option? I thought these had twin vanes. Small ones with little lag low down, and then larger ones for a big kick later...

No they are bog standard turbos just bigger. If you are talking about the new VTG turbos as found on the new 997 they are way to big to be fitted in the already packed engine back of a RS4. See she bottom picture on here: http://www.turbos.bwauto.com/en/products/vtg.asp

Dave

You are correct in saying they are not VTG but I think you will find these are hybrid turbos and quite different to standard.

Bog standard in saying no VTG !

What makes a turbo hybrid ?

As far as I understand they're off-the-shelf turbos with different wheels, mostly just compressor, fitted. Maybe some machining done. So meaning a mix and match turbo.

Hybrid sounds more fancy than it really is IMHO.

[S4RS4]

No they are bog standard turbos just bigger. If you are talking about the new VTG turbos as found on the new 997 they are way to big to be fitted in the already packed engine back of a RS4. See she bottom picture on here: http://www.turbos.bwauto.com/en/products/vtg.asp

Dave

You are correct in saying they are not VTG but I think you will find these are hybrid turbos and quite different to standard.

Bog standard in saying no VTG !

What makes a turbo hybrid ?

As far as I understand they're off-the-shelf turbos with different wheels, mostly just compressor, fitted. Maybe some machining done. So meaning a mix and match turbo.

Hybrid sounds more fancy than it really is IMHO.

A hybrid turbo is generally something that mixes two families of turbos together. In some cases, it can be Garrett cold sides on KKK hot sides. In this case, it is the K1 series (K16) and K2 series (K24) that are used. They are anything but off the shelf turbos with a different compressor wheel! They have a pretty rare centre section (bearing housing) on this application and much tighter tolerances are used than off the shelf turbos. There is also some special machining on the turbine wheels. To finish, they are hand built in very small numbers.

[njw123]

Ok, thanks.

So does this mean that if I want more power than I already have (460bhp, MTM-3), whatever turbos are used will result in either more lag, or the power simply being dumped much higher up the rev range?

I guess everyone wants more power, but if it has to come at the expense of everyday driveability, then maybe I should keep the car as it is..?

[S4RS4]

Ok, thanks.

So does this mean that if I want more power than I already have (460bhp, MTM-3), whatever turbos are used will result in either more lag, or the power simply being dumped much higher up the rev range?

I guess everyone wants more power, but if it has to come at the expense of everyday driveability, then maybe I should keep the car as it is..?

You can get a good compromise using RS6 K04 turbos with a little fettling. You can get 500 - 520 if you have headwork etc. Ask Mihnea. In my opinion (and experience), if you want much more than that (with some reliability in mind), you need to go up in the turbo group size. You can use GT 25's or these K16/24's but you are absolutely right that you will have more lag but mucho power higher up the rev range. HTH