Forum » General Tuning Discussion » Individual Lambda vs EGT for initial calibration

Individual Lambda vs EGT for initial calibration

General Tuning Discussion

Discuss all things tuning in this section. News, products, problems and results. 


Page 1
Author
388 Views

Hey guys,

I am at a bit of a turning point where I am starting to run Motec M1 level of ECU's on customers cars with all the usual fruit, (EFR turbo, sequential gearbox etc.)

Most of these clients are not local to me so I would be going with remote support at a later date to keep the car up to date as they do events etc.

I am about to pull the trigger on a AEM 4-lambda setup with backpressure compensation.

My thoughts were do have all these cars install individual Lambda ports on the manifold runners AS WELL AS egt ports at time of manifold construction or tuning, car would have the AEM 4-lambda installed and patched into the CAN network for tuning purposes to optimise cylinder lambda.

Afterwards it would be removed, and EGT sensors left in there for further monitoring / logging.

Am I shooting in the right direction by going this path / offering these services for potential clients to gain the most out of their setups. The main push for this has been a spate of different intake manifolds having some fairly large differences between cylinder filling, as well as being able to confidently trim on EGT knowing each cylinder is initially calibrated correctly.

Happy for any other tips from those that do this / calibrate high end setups as thats where I feel I am headed, so wish to gear up accordingly.

Cheers

Ben

Ultimately the more data you have, the better informed your tuning decisions can become. That being said I personally never had the opportunity to tune via individual cylinder lambda until the last 18 months and that didn't stop me turning out several tunes that ended up setting world records on the drag strip. I guess my point is that it's nice to have and if I had an option then yes, I'd love to have individual cylinder lambda, but it's not going to stop you producing a quality job if you have enough data to rely on.

The other issue to consider is the M1 ECU won't communicate directly with the AEM 4 channel UEGO. The M1 will only take lambda input from either a Motec LTC or PLM. I got around this on our 86 because we were using a Motec CDL3 dash too, so I could input the AEM lambda data into the dash and then re-transmit the data replicating the LTC CAN template. Not impossible, but perhaps difficult to do on every car. You could also write your own code in Build but again this sin't necessarily going to translate to every car you tune.

The other issue you will find is that the AEM lambda numbers wont match a LTC in the collector (or any other brand of wideband probably). The internal calibration seems to vary dramatically from brand to brand so you can only use the lambda data realistically for cylinder matching, which is ok since that's why you're using it - I still use collector lambda to adjust my overall mixture and consequently the back pressure compensation becomes a little less important too if you're using the individual lambda in this way.

My own experience has been that EGT is a useful addition that has served me well in individual cylinder tuning on high end applications. Yes, compared to individual cylinder lambda, there may still be discrepancies but these tend to be at lower load/boost where you're less concerned about it. Individual lambda is great, but does add a layer of expense and complexity that might not offer the ultimate gains you might expect.

I'm not sure if the above helps or hinders your decision sorry.