Tuning with AF meter
 

This was brought up on another thread and I asked a few questions but thought this deserved its own. Ron said he was running in the 15s and 16s for AF mixture and from what I have read it seems that would be a bit lean seeing as the stoichiometric number is 14.7 parts air to 1 part fuel. Timing was alos mentioned and I was wondering how you can tell when it is best to make a timing change or a mixture change? And last can anyone make recommendations as to what brand meter works best and what is needed?

Re: Tuning with AF meter
 

15 and 16 is not uncommon for part throttle mixtures. Not good for power.

Re: Tuning with AF meter
 

Speaking AF meters, anyone know what sort of readings you should get at idle?

Re: Tuning with AF meter
 

This is an important distinction. The carburetor Ol' Ron was talking about is on my engine, in a 3300 lb '53 Victoria. We're seeing 15s and 16s in easy steady cruise, but when you call for more power the A/F drops to the 12s and 13s as it should.

Re: Tuning with AF meter
 

Hey. How 'bout telling a dummy what an AF meter is.:confused:

Re: Tuning with AF meter
 

Sorry Henry. Air/Fuel mixture.

Re: Tuning with AF meter
 

I get the same readings as Richard running 2 94's. I also have a vacuum gauge which reads 13-15 at cruising speeds, 20 at idle.
Butch

Re: Tuning with AF meter
 

It sounds like you guys are running alittle lean of stokeometric, which if memory serves me right is 17:1. I thought that with the bad reputation of flatheads overheating abit rich might be helpful. Say 17.5:1. I sure won't claim to be correct with todays modern fuels which change things abit. Just some random thoughts. Rod

Re: Tuning with AF meter
 

Butch>>>I also have a vacuum gauge which reads 13-15 at cruising speeds, 20 at idle.>>>

Out of curiosity, what units are marked on your guage? PSI, KPa, bar, etc.? Thanks.

Jack E/NJ

Re: Tuning with AF meter
 

I took the time to refresh my memory and it all seems better now. Rod

Re: Tuning with AF meter
 

Rowdy number represents the air so the higher it is the leaner it is. Exact mixture is 14.7:1. Under power you want it lower and like others said art part throttle cruising you want it a little higher.

Re: Tuning with AF meter
 

Like I said I had to refresh my memory as it has been 20 years since tech school, but books are still on the shelf and have to read from time to time. Rod