Towing w/ a radix
Oct 14, 2007 | 09:30 AM
#11
Also anytime you are in boost(turbo or SC) it requires a richer fuel mixture say 11-12:1 AFR rather than 14.7:1 when not in boost. So it is more than just increasing the fuel flow to match the airflow. That richer mixture is what makes the 2 MPG difference under cruising conditions in my case, even though I am revving a lot higher in 3rd gear. So the real loss from the richer mixture is actually greater than 2 MPG.
The SC does making passing and getting rolling a breeze when towing though.
The SC does making passing and getting rolling a breeze when towing though.
Oct 14, 2007 | 08:41 PM
#12
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Joined: Sep 2003
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From: Las Vegas, NV
I agree that keeping out of power enrichment is going to be better. You're much better with an N/A engine that downshifts when it needs to than going into boost to make the power you need. Only diesels get better milage when towing with a turbo, not gas engines.
Oct 15, 2007 | 08:29 PM
#13
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From: BOULEVARDS OF BOOST CALIFORNIA
I live in California and there is only a halve dozen BIG mountains to climb in this state and I came from Illinois were mountains are not a big thing but most mountains take less then 3 minutes to climb and being in PE for 3 minutes strait is not all that much to worry about. I just towed a crew cab HD 2500 on a tandem trailer behind a 2007 crew cab 5.3 1500 up some big mountains with no problem. Keeping in in third gear and keeping the rpm range in the 2300-2800 range helps keep it out of PE 80% of the time like someone earlier said gear reduction works wonders. I do feel if you are towing over 10000 lbs often get a diesel!. Also 12.5 AFR PE compared to 10.1 COT that the factory has you at is no big savings.
Oct 15, 2007 | 08:31 PM
#14
I live in California and there is only a halve dozen BIG mountains to climb in this state and I came from Illinois were mountains are not a big thing but most mountains take less then 3 minutes to climb and being in PE for 3 minutes strait is not all that much to worry about. I just towed a crew cab HD 2500 on a tandem trailer behind a 2007 crew cab 5.3 1500 up some big mountains with no problem. Keeping in in third gear and keeping the rpm range in the 2300-2800 range helps keep it out of PE 80% of the time like someone earlier said gear reduction works wonders. I do feel if you are towing over 10000 lbs often get a diesel!
Oct 15, 2007 | 09:13 PM
#19
I live in California and there is only a halve dozen BIG mountains to climb in this state and I came from Illinois were mountains are not a big thing but most mountains take less then 3 minutes to climb and being in PE for 3 minutes strait is not all that much to worry about. I just towed a crew cab HD 2500 on a tandem trailer behind a 2007 crew cab 5.3 1500 up some big mountains with no problem. Keeping in in third gear and keeping the rpm range in the 2300-2800 range helps keep it out of PE 80% of the time like someone earlier said gear reduction works wonders. I do feel if you are towing over 10000 lbs often get a diesel!. Also 12.5 AFR PE compared to 10.1 COT that the factory has you at is no big savings.
Oct 15, 2007 | 09:19 PM
#20
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Joined: Sep 2003
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From: Las Vegas, NV
I live in California and there is only a halve dozen BIG mountains to climb in this state and I came from Illinois were mountains are not a big thing but most mountains take less then 3 minutes to climb and being in PE for 3 minutes strait is not all that much to worry about. I just towed a crew cab HD 2500 on a tandem trailer behind a 2007 crew cab 5.3 1500 up some big mountains with no problem. Keeping in in third gear and keeping the rpm range in the 2300-2800 range helps keep it out of PE 80% of the time like someone earlier said gear reduction works wonders. I do feel if you are towing over 10000 lbs often get a diesel!. Also 12.5 AFR PE compared to 10.1 COT that the factory has you at is no big savings.
When you were in p.e. for 3 minutes straight I'm guessing this is something you worked the a/f ratio on? I would be concerned about cooking the cats.