Sorry if this question has been asked before. I don't seem to be able to find an answer from my searches. I'm new to EFI and ECU tuning, so hopefully my questions will make sense.

Is there a practical engine rpm limit that the 16197427 PCM can safely manage the engine? Putting it another way, how high can a 16197427 controlled V8 engine spin before the PCM can no longer keep up with fuel and spark calculations?

I'm presently collecting parts for a project that will use a stroked GM 454 (496 with a 4L80e transmission). After doing a fair amount of reading on this forum and over at Gear Head EFI, I feel the 16197427 PCM would be a good choice for engine management. My plan is to modify the 16197427 motherboard for MPFI. I understand it's still a batch fired fuel injection schema. I also plan to use the DIS Northstar ignition system for spark.

My question came up because I've recently stumbled across some articles that talk about the raw processing limitations of some of the OEM ECU's, and their effects on maximum RPM. Just curious to know if my plans for the 16197427 are even possible...

I'm guessing there is no easy answer to my question, but maybe from some of the experiences of others, there might be a safe RPM limit recommendation to not cross over.

I hope this all made sense.

Thanks in advance for your thoughts.

David

 

There really isn't a limit unless one is running a 14K RPM Indy engine. The reason is that the injection and ignition timing are handled in hardware.

The biggest issue will be the limited upper RPM of the tables. In $0E it looks like the main SA and main VE table do go to 6400 RPM.

RBob.

 

Honestly even lack of control above 6,400 rpm is not a huge issue. I have used $0D on a 406 small block with dual TBI units and a tunnel ram on a 406 small block with a solid roller cam. It was turning 7,200 rpm. The entry for fuel and timing at 6,400 is used from 6,400+ and in my experience the VE is dropping by that point and you might lose a touch of HP from the fueling going rich, but its honestly safer to be a touch fat at that RPM anyway.

 

Agree, although some code bases do have relatively low upper RPM limits. Some as low as 3600 RPM for spark advance. I did check the $0E code and found that it is at 6400 RPM. Was a bit surprised.

RBob.

 

Thank you RBob and Fast355!

This is great news. I'm feeling very optimistic about this.

I would love to use something a little more modern like the 12200411 for engine and transmission control, but I haven't found a way past the high admission price for all the kit needed to tune these OBDII controllers. I completely understand the great value in the HPTuners and EFILive packages for people who do this for a living. But for me it's a little steep for someone just getting started.

Thanks again,

David