cruising air/fuel ratios??? What's typical?
12-20-2003, 04:17 PM
#1
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cruising air/fuel ratios??? What's typical? Hey guys,
I'm trying to get the best possible fuel milage from my ride. I have wideband O2s so I can see exact afr and tune accordingly. Right now I have it set up for about 15:1 to 15.5:1 when I'm at light load cruising.
Does anybody know what the factory LS1s are running at light load? Leaner? Richer?
I have an aftermarket AEM ECU so I can't relate to the LS1 edit numbers. Please help, my wallet is suffering from low mpg. I get about 12-13 around town. It's a completely stock 98 corvette engine.
Thanks
I'm trying to get the best possible fuel milage from my ride. I have wideband O2s so I can see exact afr and tune accordingly. Right now I have it set up for about 15:1 to 15.5:1 when I'm at light load cruising.
Does anybody know what the factory LS1s are running at light load? Leaner? Richer?
I have an aftermarket AEM ECU so I can't relate to the LS1 edit numbers. Please help, my wallet is suffering from low mpg. I get about 12-13 around town. It's a completely stock 98 corvette engine.
Thanks
12-20-2003, 08:52 PM
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Its pretty bad to have the car running really lean and still get horrible gas mileage. The stock pcm wiill try for 14.7 which is richer than you have it set.
Gary
Gary
12-20-2003, 09:54 PM
#5
The stock PCM shoot for 14.7 when in closed loop, but uses different a/f ratio's when in open loop.
Open loop a/f's differ from 13.1 to 14.7 depending on the load of the engine (not including Performance Enrichment).
Are your Follower tables set correctly? Does the car backfire on the way down? Is there a BIG difference between your freeway MPG and 'around town' MPG?
Open loop a/f's differ from 13.1 to 14.7 depending on the load of the engine (not including Performance Enrichment).
Are your Follower tables set correctly? Does the car backfire on the way down? Is there a BIG difference between your freeway MPG and 'around town' MPG?
12-21-2003, 03:21 PM
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Thanks for the response guys. It turns out I was a lot richer than I thought. I ran my truck on the dyno last night. I did a lot of constant load testing. I was able to tune for most driving situations. It turns out most of the time I was running about 12.5 to 13:1. On the dyno I was able to tune my fuel map one cell at a time and changed them to run about 14.7:1. It was a little interesting once I got it back on the street because I was running about 16:1 cruising through traffic. It sure smoothed everything out. Then I have it set to go to 13.5 to 14.1 when I give it some gas. And about 12:1 under full throttle.
I also tuned for max power. To the rear wheels I got:
301 hp @ 5800 rpm
320 ft-lb @ 4500 rpm
The torque stayed above 300 from 3000 to 5000rpm. It also was over 300 hp from 5700 to my redline of 6300.
I was pleasantly surprised to get those numbers. Not bad for a stock corvette engine through an automatic.
I also tuned for max power. To the rear wheels I got:
301 hp @ 5800 rpm
320 ft-lb @ 4500 rpm
The torque stayed above 300 from 3000 to 5000rpm. It also was over 300 hp from 5700 to my redline of 6300.
I was pleasantly surprised to get those numbers. Not bad for a stock corvette engine through an automatic.
