Dr L-88

What are the best (for the money, not necessarily the most expensive) devices for measuring air to fuel ratio and engine vacuum ?

olescarb

To me the most accurate way to check air/fuel mixture is with a 5-gas exhaust gas analyzer because it allow you to read the mis-fire rate (HC), engine efficiency (co2), air/fuel mixture (CO), exhaust dilution (o2) and if the spark timing is too advanced for the octane of the gasoline (NOx). Any smog station can give you a print out of the readings for $30 or $40, a wide-band "oxygen" sensor based air/fuel meter is a great tool but the accuracy of the readings can be effected by engine misfire or any exhaust leaks. I use a portable 5-gas analyzer plus we have both Innovate and FAST wide-band sensor based air/fuel meters that we use for tuning. If you are interested the following link is to a article on air/fuel mixture tuning

http://www.enginebuildermag.com/2008...fuel-equation/

Any brand vacuum gauge is fine depending on what you are doing or if you have money to spend Bosch has a engine analyzer (MTS5200) that can allow you to look at the vacuum signal of each cylinder in real time if you are looking for an advanced diagnostic tool.

I hope this helps Henry @ oles carb

Dr L-88

Have any of you used this one, and if so, were you satisfied with it?

Thanks

http://www.ebay.com/itm/Edelbrock-6593-Electrical-Air-Fuel-Ratio-Monitors-EDE6593-/360831709538?pt=Race_Car_Parts&hash=item54033ef162&vxp=mtr

olescarb

[QUOTE=Dr L-88;1588170670]Have any of you used this one, and if so, were you satisfied with it?

No, I have not used the edelbrock unit but it uses a narrow band "oxygen" sensor which is only accurate at 14.7/1 A/F mixture. Innovate offers a wide band unit http://www.summitracing.com/parts/inn-3802/overview/ that uses a wide band sensor that is a lot more accurate as long as the misfire rate is low and no exhaust leaks.

Dr L-88

I'm well before the tuner / ricer generation.......................but this looks pretty interesting.

olescarb

[QUOTE=Dr L-88;1588170993]I'm well before the tuner / ricer generation.......................but this looks pretty interesting.

I don't understand the before the tuner / richer generation reference but as long as the exhaust sample reference is un-diluted (no leaks) and the misfire rate is low the a/f mixture readings are dead on.
Henry @ oles carb

devildog

I have an Innovate which I have used for some years on my 61. It is easy to use and responsive. I suggest weld pungs in each exhaust pipe and switch the O2 sensor for reading in each exhaust.

I just run the cable thru the cowl vent to use while driving on highway.

Joe

cbernhardt

I also have an older Innovate LM1 which I used to tune the Ramjet 350 in my wife's '62. I have had no problems with it. One of the reasons I chose this unit was that it has an analog output which I was able to route into the Ramjet controller so that I could log the engine parameters and the A/F ratio in the same file. This made comparisons of changes much easier.

Charles