Rick

I'm after a favour if possible. Apparently in a recent issue Dave Walker did a RR test on the ST170 engine while altering the VVT. A photo/scan of the article would be much appreciated

Rick

tabetha

You have pm
tabetha

Big Will_

If you get any info Rick, that would be interesting to see

RichieST

iTrader: (2)

I'd lke to see it too

SiZT

tbh its most likely information that you'll already know

tabetha

I have the article and, it's more to do with mpg on soft cam setting at crusing mode.
"I pretty much covered all the mapping then did a power run with the cam on the soft setting.
The run was then repeated on the power setting and the two power curves(power and economy) compared.
I was quite happy with the results but then I switched to the economy map for some light throttle and cruise tweaking of the mixture.
I usually do one map for full power and then set up another map for road driving where I weaken out the mixture a little at 50/60/70 mph in top gear.
Just out of curiosity I decided to see what the cam was doing on part throttle as opposed to full throttle power runs.
The result was very interesting.
For power the map needed to switch at about 2500rpm but on half throttle at 3500rpm it needed to stay on the soft cam timing.
The actual power differenc eon 40% throttle was the same with the cam switched either way, but the fuel consumption changed drastically.
On the power cam timing I was using twice the fuel of the softer setting, to get the same AFR.
I seldom theorise because I prefer to measure things, but in this instance I think the fuel on the power cam timing setting was going straight through the engine and out the exhaust.
Therefore you had to put a lot more fuel into the engine to run the same mixture as you had on the softer cam setting.
I set the car up to run soft cam timing up tp 2500rpm but then only only to switch after 50% throttle.
It's in the MAY edition of PPC
tabetha