Supercharger blanking plate

[Yega 10]

Could you point him in the direction of this thread Jim?

[Yandards 0]

Hallo!

 

Riley is quite correct when he says that the charger is only lubricated by the engine oil supply at the bearings.

 

The sealing strips are, I believe, made up of a hard PTFE based item and as such are self lubricating.

 

If you look at any of the VW engines they all return emissions to the inlet air supply for regulatory purposes.

 

As for boost return deletion, aside from oil vapour you will also loose some engine efficiency as the recycling of boost air is removed from the system, the downside of boost return is that the tiny intercooler on the G60 can't cope with the recycled boost air at all well which robs power from the engine.

 

The boost return system also does some other clever tricks, the ISV is 2 way on a G60 for starters; it provides both air into the inlet manifold from the boost return to clean up the idle behaviour and it also dumps manifold pressure into the boost return line from 5600 RPM to 6200 RPM (ECU RPM cut point) by 0.15 bar. Finally the ISV dumps inlet manifold pressure to boost return when engine knock is detected by a factor of 0.4 bar.

 

So if you want to run boost return deletion you will need to a filter for the underside of the throttle body that goes to boost return to prevent dirt ingress into the engine, a filter on the ISV so that can continue to function as required and finally consider that without an ECU remap you will loose boost pressure into the engine gradually from 5600 RPM upwards.

 

As for what would I do, I would be happy to run without lubricating the PTFE seals in the charger with some gunk every few miles, but I do feel the boost return system is useful in that it makes the engine more efficient - you just need a better chargecooling system - which was why I ran a PWR charge cooler setup and BBM solid boost hoses instead of the plastic crap.

 

I don't have any hard figures and I was going to fit a CNC G60 cylinder head (which would have been very interesting) but on a standard charger & pulley, RSR outlet, BBM solid boost pipes, PWR chargecooler, knife edged throttle body and a DG custom ECU map my G60 was keeping up with Jim's VR through the gears so I suspect it was around the 190bhp mark with ease - all that and my max boost pressure never got above 0.7 bar.

 

A smaller pulley does achieve all that but I could still fit a smaller pulley and port the charger for even more (If I still had a G60!).