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Some early results 

I had a dyno session booked for 25th March at SAS.

I was advised that while initial results looked promising, the fueling was a little lean.

Prior to the run I'd not been pushing the engine too hard as I did have a feeling that this 

would be the case based on experience with similar head work on C30SE engines.

 

However I should have had a little more faith in the ecu programming and learning capabilities

 to push harder. SAS used a wide band lambda sensor and readout that indicated the lambda.

Looking around the internet I found a product made by www.innovatemotorsports.com

which is a kit containing the wideband lambda and integrated display and data logger (LM-1). 

Another member in our club already had one of these units, good enough recommendation so yet 

another ebay purchase is made.....

 

So now I can look at fueling during my own test runs and record the data to view back home.

With each run I pushed a little harder, and did find that the fueling became richer, but I still regarded it a 

little lean in places. 

 

 

Approximately I'm looking for a drop in lambda from 0.9 to about 0.82 as 

boost rises to max, this plot shows a eventual fall to 0.8, but then it 

rises again with rpm.........what rpm ?, yes I know, can only estimate the rpm 

for now, the LM-1 kit with a auxillary device will allow logging of rpm and some 

other inputs, ie map would also be good. I will be ordering this very soon.  

Also what I needed was some data from a standard LC setup ;-) , big thanks 

to Phil Gummery for allowing me to weld a lambda boss into his exhaust, then 

a few runs up the road and some data logging

 

The plots do look quite similar, but without rpm or map it's difficult to correlate exactly 

what is happening.

   

I have also been taking logs of the ALDL data stream, which MR had checked over 

for me, one noticeable point was a lack of any combustion knock...actually a good 

thing !, but unusual for a LC to have so little, for now I can only put this down to a 

cleaner air charge, I think before quite a bit of oil vapour was being burnt.

 

By 8th April 2006 I covered approx 500miles, power feels quite good.

Time for another spin on the rolling road at SAS in Aldershot, during a club rolling road

 dayto find out exactly what power I now have. 

This time Tim at SAS bolted a sensitive knock sensor to an inlet manifold stud, he 

was able to monitor for knock through some headphones. He commented that while

 there was a little, it was insignificant and would not have been picked up by the LC 

knock sensor, in other words nothing to worry about. I did manage to get a fueling 

plot from one of the dyno runs:-

 

 

This plot was taken during a 5th gear run accelerating to 172mph, something not possible on

 the open road !

It also contradicts the earlier plot which shows a lean part at higher rpm, while this one shows 

a rich plot for the same period. However there is still a lean part mid-way. I think the lean spike 

indicates either a miss-fire 

as the lambda is measuring the un-burnt oxygen, or there really is a very lean snap ?? 

I really do need to plot rpm/map/tps ect before any real judgment can be made about where 

to add fuel.

 

Ok so here's the dyno plot from SAS :-

429bhp and 416ft/lb torque, I'm quite pleased, especially if you compare to the plot from last year:-

 

 

 

I have some way to go yet though.......

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