Tuning - airflow and EGR

pondweed · Post by **pondweed** » Wed Sep 26, 2007 10:38 am

again with reference to the improvements on the CDT Rover/BMW 2.0d unit, I wonder whether:
1. HDi airflow is a limit to bhp on the standard cars and whether opening up the intakes has been sucessful? (CDTs were deliberately choked by BMW before they let Rover go so it didnt compete with their own 320d)
2. Has anyone developed an EGR bypass for the HDi engine? (Rover/BMW/landrovers benefit from a special casting that doesnt have any of the restrictive valve blocking airflow, and there is a stub to reattach the now-non-functioning exhaust entry)
3. Are there Mass Airflow meter (or any other) problems with the HDi engine that need sorting/checking to ensure best running?

mbell666 · Post by **mbell666** » Wed Sep 26, 2007 12:26 pm

1) not sure what you mean there, I am not aware of any restrictions but in the air system to limit the bhp.

2) Most people round here haven't done anything with the egr (apart from when it is bust). If they do they normally just remove and block the vacuum pump that drives the egr.

3) reports of Mass Air-flow meter failures seam to be pretty low for the HDi's.

pondweed · Post by **pondweed** » Wed Sep 26, 2007 3:51 pm

[quote="mbell666"]1) not sure what you mean there, I am not aware of any restrictions but in the air system to limit the bhp.
quote]
thats all very helpful thanks. Re: point1, your reply is a bit ambiguous too (!) but I guess I meant it became very clear on the inlet route into the R75/MGZT CDT airbox, their were all sorts of over-restrictive baffles which did more that just keep spray out, in opinion of day-to-day users anxious to improve operating efficiency.

I'll have a look....havent opened bonnet yet...

mbell666 · Post by **mbell666** » Wed Sep 26, 2007 8:08 pm

I not familiar with the BMW/MG "lump" so wasn't certain what you where on about.

I've never taken my air system to pieces but am not aware of any baffles or other things inserted to reduce air flow. The air intake is on the right of the engine bay somewhere around the bottom of the air-box. I think it just a pipe feed into the air box. Probably fairly easy to take a look.