MadMav
Colorado Springs, CO
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For mountain towing the turbo will be the best bet by far.
Mav
"A fifth wheel trailer is a bi-level towable mobile home."
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music69
Tennessee
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MadMav wrote:For mountain towing the turbo will be the best bet by far.
Mav
??? Doubt it. The EB has to boost pressure by 70% (10 psi) to just *match* the 6.2 natural displacement (air flow) at any rpm, regardless of ambient pressures.
* This post was
edited 02/10/12 08:36am by music69 *
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music69
Tennessee
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Specs on the GM 6.2: GM 6.2 Dyno
Points of note:
~350 ft/lbs @ 1500 rpm
~380 ft/lbs @ 2000 rpm
417 peak ft/lbs @ 4300 rpm
There's good reason you'll never see Ford line up their EB against the GM 6.2 or Tundra 5.7. I'm not knocking on the EB at all, but some folks seem to get a little carried away with the notion of turbos, and what they can (and can't) do.
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goducks10
Keizer OR
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music69 wrote:Specs on the GM 6.2: GM 6.2 Dyno
Points of note:
~350 ft/lbs @ 1500 rpm
~380 ft/lbs @ 2000 rpm
417 peak ft/lbs @ 4300 rpm
There's good reason you'll never see Ford line up their EB against the GM 6.2 or Tundra 5.7. I'm not knocking on the EB at all, but some folks seem to get a little carried away with the notion of turbos, and what they can (and can't) do.
Not sure where your gettng those dyno results from but they look kinda high to me. Heres some form another site that are more realistic. Those might be engine ratings but no motor puts out the rated TQ at the rear wheels on a dyno.
Another thing to factor in is the loss of HP/TQ at higher elevations, the Eco won't lose any like the 6.2 will. So unless you just tow at sea leavel you will struggle to keep up at mtn passes.
http://www.hypertech.com/PerformanceGrap........m/32010_2011_2012_GM_2_F_Models_6_2L.pdf
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music69
Tennessee
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goducks10 wrote:Not sure where your gettng those dyno results from but they look kinda high to me. Heres some form another site that are more realistic. Those might be engine ratings but no motor puts out the rated TQ at the rear wheels on a dyno.
Another thing to factor in is the loss of HP/TQ at higher elevations, the Eco won't lose any like the 6.2 will. So unless you just tow at sea leavel you will struggle to keep up at mtn passes.
Those numbers are from the link provided, which are GM specs at the crankshaft (the same SAE method Ford specs their motors). The EB must boost pressure to compensate for it's lower displacement, where the 6.2 is using natural aspiration.
6.2L x 2000 rpm = 12400 L/m of air
3.5L x 2000 rpm = 7000 L/m of air
The EB needs to boost pressure by (12400-7000)/7000 = 77% to just *equal* the 6.2L oxygen flow, and that's true at any altitude or O2 concentration.
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ronhuntfish
Michigan
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To answer your question...
I have a 2011 Silverado with the 6.2L, max tow package, crew cab 4X4, max trailer weight of 10,400. I have a TT that is 33feet from hitch to bumper. It is about 6200 pounds loaded to travel. This summer we took a trip west (5000 miles towing) and never had a problem. Always had plenty of power. Drove in mtns, in 103degree heat, and was never concerned. Got about 10mpg for the trip. When not towing I get about 1.5mpg less than I did with my 5.3L Silverado.
The only thing I would consider is tires. Mine has P rated tires. I think it would have been better with LT, but I have no verifiable proof of that, since I never changed them to compare.
It does state that 91 octane gas is recommended, but have been using only 87 octane for a while now with now known problems, and 43,000 miles.
Crossroads Sunset Trail 29QB
2011 Chevy Silverado, 6.2L, 3.73, 10,400 Max tow.
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MadMav
Colorado Springs, CO
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music69 wrote:MadMav wrote:For mountain towing the turbo will be the best bet by far.
Mav
??? Doubt it. The EB has to boost pressure by 70% (10 psi) to just *match* the 6.2 natural displacement (air flow) at any rpm, regardless of ambient pressures.
You don't know much about altitude's effect on power do you. A forced induction engine losses power at 50% the rate of a naturally asperated engine due to elevation. Therefor towing in the mountains at altitude is much better with a forced induction engine.
Mav
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music69
Tennessee
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MadMav wrote:You don't know much about altitude's effect on power do you. A forced induction engine losses power at 50% the rate of a naturally asperated engine due to elevation. Therefor towing in the mountains at altitude is much better with a forced induction engine.
Mav
See post above. Oxygen concentration falls linearly with atmospheric pressure as you climb. The 6.2L pulls 6.2L per rev, where the 3.5L draws 3.5L per rev. The turbos "compensate" by boosting air pressure above ambient. If the EB is capable of compensating for the full difference in natural displacement, then at best, the turbo 3.5 would perform identical to the 6.2L. That's true at all elevations (ambient atmospheric pressures). There's no magic, unless there's some wizardry that I'm not aware of? I'm certainly open to learn.
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music69
Tennessee
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ronhuntfish wrote:To answer your question...
I have a 2011 Silverado with the 6.2L, max tow package, crew cab 4X4, max trailer weight of 10,400. I have a TT that is 33feet from hitch to bumper. It is about 6200 pounds loaded to travel. This summer we took a trip west (5000 miles towing) and never had a problem. Always had plenty of power. Drove in mtns, in 103degree heat, and was never concerned. Got about 10mpg for the trip. When not towing I get about 1.5mpg less than I did with my 5.3L Silverado.
The only thing I would consider is tires. Mine has P rated tires. I think it would have been better with LT, but I have no verifiable proof of that, since I never changed them to compare.
It does state that 91 octane gas is recommended, but have been using only 87 octane for a while now with now known problems, and 43,000 miles.
Good to hear. Your camper is similar to mine (Sunset Trail ST30BH), and I'm currently pulling w/ an '08 5.3L/3.73. Did the 6.2/6-spd/3.73 combo make as big a difference as it seems that it would? (i.e., do you feel that it was worth the added expense and a little worse mpg?)
* This post was
edited 02/10/12 11:02am by music69 *
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ronhuntfish
Michigan
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music69 wrote:ronhuntfish wrote:To answer your question...
I have a 2011 Silverado with the 6.2L, max tow package, crew cab 4X4, max trailer weight of 10,400. I have a TT that is 33feet from hitch to bumper. It is about 6200 pounds loaded to travel. This summer we took a trip west (5000 miles towing) and never had a problem. Always had plenty of power. Drove in mtns, in 103degree heat, and was never concerned. Got about 10mpg for the trip. When not towing I get about 1.5mpg less than I did with my 5.3L Silverado.
The only thing I would consider is tires. Mine has P rated tires. I think it would have been better with LT, but I have no verifiable proof of that, since I never changed them to compare.
It does state that 91 octane gas is recommended, but have been using only 87 octane for a while now with now known problems, and 43,000 miles.
Good to hear. Your camper is similar to mine (Sunset Trail ST30BH), and I'm currently pulling w/ an '08 5.3L/3.73. Did the 6.2/6-spd/3.73 combo make as big a difference as it seems that it would? (i.e., do you feel that it was worth the added expense and a little worse mpg?)
Well, I bought this truck just before I bought the TT so I can't really compare how the two towed it. I too had concerns on how the old truck would tow, and wanted to make sure i had enough truck (old one was an 08 with 75,000 miles) for TT before we made our big family trip west. That being said, I am very happy with the truck and I do think it was worth it. It runs great and there is for sure a improvment in power and towing capability. Maybe if I did less towing I'd feel different.
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