Rescue Rogers

So for anyone that has an air fuel ration gauge, what would be the preferred readings for part throttle acceleration, cruise and power. I have a 14.2 on average reading at idle, it does jump a little but its pretty close. But thats fine. So what I need to know is what the off idle readings should be. Off idle acceleration and cruise its 12.5 to 12.9. Is 13.5 what I should be shooting for or higher? Thanks for any info or opinions.

Scott

Kingtal0n

For stock engines it can be quite different than modified engines

I stick 14.8 to 15.4 idle
15.2 to 16.4 cruise
13.5 to 14.2 part throttle (up to 4" Hg)
12.5 to 13.0 part throttle (3" to 1" Hg)
12.5:1 WOT (0" Hg to 6psi boost)
12.0:1 WOT (6psi to 10psi boost)
11.5:1 WOT (10 to 14psi boost)
11 flat for 15-18psi of boost or even 10.8:1

This is for gasoline, 93 octane, 9.5:1 compression, high mileage engine using a turbocharger.

Rescue Rogers

Thanks. I'll add this to give everyone a better idea of where I'm at

14.2 idle
12.5 to 13 at cruise
10 at wot with the 4 barrel in
First fill up read about 11 miles per gallon but thats with a lot of idling and testing
The 1902 has a .026/.037 stock rod and I jumped up to a .072 jet since it was so lean with a .069 jet
Im going to bring it one jet size down to see what happens at cruise and get some readings, then maybe start with the rods. I didnt look to see the Hg" through transition, its about 17hg to 20 hg at cruise

I've got a modified 327. 93 octane, 11:1 compression, aluminum 205 heads, CompCams .501 intake/.510 exhaust and Dewitts radiator with a big single spal fan. It runs great, lots of power everywhere, but it is rich.

Its a copycat build of a Hotrod Magazine story that got 450HP with my intake and 460 with a single plane and headers. I'm guessng I'm down around 420 to 450 hp range because I'm not runnning the headers, but do have 2.5" ramshorn though the side exhaust. All the midrange torque and hp readings should be the same.

I'll keep playing with the jets and rods. Its a New old stock 1902 Edelbrock quadrajet that I've done a few Cliff Ruggles mods to, to get it running properly. I've got a calibration kit that came with some rods and jets so I've got a lot of combos to go through.

resdoggie

Your idle is fine. Work on main jet size next for cruise. My Holley liked smaller primary jets, #67's, to get a cruise afr of 13.8:1. I had #65's and afr of 14.5:1 but the engine just seemed a bit off so hence the 67's. My wot was 12.8:1 and vacuum 0", so that worked for me. I think you know what direction you need to go and you have a Qjet vice Holley but the principles are the same. Work one fuel circuit at a time only if it needs work. Enjoy!