Are there one or two decent (accurate) air fuel monitoring systems out there that work well but don't break the bank?

Spend the money on a LM1

I just bought an LM-2 which is the sucessor to the LM-1. I have to say that at this point I am not happy with it. It does a great job on the AFR, but the RPM module does not work with a stock GM HEI (no box). I was warned about this up front and the vendor suggested I buy the LM-1 because everything works great with the LM-1.

Problem is it is no longer made. You can still get a new one from back stock but I hated to invest in a product that was discontinued before I even bought it.

If you don't care about mapping RPM it is fine. It has a very nice recording system which is a must in my book.

It still may be the best one out there but I was really wanting the RPM piece to work properly. I think it does work OK if you are running an MSD box and get the tach feed from there.

Spend the money on a LM1

i just bought one on Ebay, paid less then $200.00

got it today, not installed yet!

Nice. Looks like the way to go. Thanks!

I just bought an LM-2 which is the sucessor to the LM-1. I have to say that at this point I am not happy with it. It does a great job on the AFR, but the RPM module does not work with a stock GM HEI (no box). I was warned about this up front and the vendor suggested I buy the LM-1 because everything works great with the LM-1.

Problem is it is no longer made. You can still get a new one from back stock but I hated to invest in a product that was discontinued before I even bought it.

If you don't care about mapping RPM it is fine. It has a very nice recording system which is a must in my book.

It still may be the best one out there but I was really wanting the RPM piece to work properly. I think it does work OK if you are running an MSD box and get the tach feed from there.

Have you posted your questions on the forum ? For my money the forum is as good or better then the unit itself .

I bought an AEM and have been happy

Have you posted your questions on the forum ? For my money the forum is as good or better then the unit itself .

I have spoken to Philipe many times at Innovate and done all he said and nothing works. I think it is a design flaw in the LM-2. It's weird that it worked great on the LM-1 then they screwed it up. Live and learn...I was warned ahead of time.

The AF monitor piece works great though.

All the good AFR monitors use either the bosch or NGK heated wideband sensors.
The NGK is more expensive.
Many can be ordered with either.
They are all equally accurate.

The "biggie" is what you can do with them.

You need to see rpm, AFR, and manifold vacuum all at the same time.
I have all the gauges in my dash, but trying to remember what they all say and tuning from them is tough.
Really, you need to datalog.
and you need rpm and vacuum in addition to afr. Knowing you went lean does little good if you don't know "under what conditions"

You will wonder how you ever did without when you get it installed.
It is a great tool.