Torque! Rocket power vs LS power

[olds307 and 403]

Well, I guess I can't argue with that type of quantative data. It's official, all LS engines suck.

Below 4000 rpm. I towed my old 16 foot Vanguard with my Inlaws 04 Avalanche 5.3/4L60E/3.73 I believe. My 94 did better in the low rpms, towing the same boat. I sorry that these trucks don't perform below 4000 rpm. Above 4000 rpm is different story. I don't know why GM tuned them like this.

 

[olds307 and 403]

Can't imagine why anyone would buy gas trucks if towing any kind of weight is going to be a regular part of the program

Our old 05 6.6 Duramax/Allison was a much better towing truck than this 11 6L/6spd. It had about 350,000 km on the Duramax.

 

[ck80]

Apparently a 6.2 is the truck to get, too bad very few are equipped with them. The rest are a dog fest. Again, not talking about the 2014 and up direct injection motors, way better.

Disagree.

Since you're looking 2013-down years it's really the 8.1L trucks are the ones to get. Gets you a superior motor and out of an ls altogether.

 

[Supercharged111]

Below 4000 rpm. I towed my old 16 foot Vanguard with my Inlaws 04 Avalanche 5.3/4L60E/3.73 I believe. My 94 did better in the low rpms, towing the same boat. I sorry that these trucks don't perform below 4000 rpm. Above 4000 rpm is different story. I don't know why GM tuned them like this.

My observation has been that they cross over closer to 3000, but same idea. Far as I can tell, they lack low end torque for emissions. The cam profiles suppress cylinder pressures which keeps NOx at bay. The rest of the motor breathes which gives it legs.

 

[84 W40]

That graph of the olds 350 reminds me of a stock W31 motor with a modern grind cam that bumped hp level. The Tq is about the same when it came off the assembly line 51 years ago a W31, correct me if I'm wrong getting older. Could that olds put out little more TQ at a higher rpm absolutely it depends on the builder.
Both engines put out great numbers, ls has the advantage and better heads.
When comes to peak TQ at a certain rpm its all preference.

 

[olds307 and 403]

What LS have variable cam timing? I am wondering if most of trucks I drove don't have it? No one said the LS doesn't have a big advantage in the higher rpm, especially with the Olds stock iron heads, under 200 cfm intake and maybe 160 cfm in non W31 form. Probably 210/170 in W31 form.

 

[Supercharged111]

What LS have variable cam timing? I am wondering if most of trucks I drove don't have it? No one said the LS doesn't have a big advantage in the higher rpm, especially with the Olds stock iron heads, under 200 cfm intake and maybe 160 cfm in non W31 form. Probably 210/170 in W31 form.

It only came on the GenIV stuff, and not all of it. Maybe GenV too, but 100% not on the GenIII stuff.

 

[Northernregal]

Back in the day a coworker and I had identical 2001 5.3 powered 1500s. Mine was a ROCKET until I got a new 2006 2500HD. My coworkers truck was absolutely garbage, no power, never had the right gear and pretty much felt like a 4.3 V6.

I put 300k km on that truck and 160k km on the 06, 6.0. The 6.0 had 4.11 gears and drove like an old farm truck that was worn out. I don't think it's the motors, I think it's the way GM had then matched to the trans and the tuning.

I had a 2004 Avalanche with a 5.3 and when I moved in 2016 I did a trip with a way overloaded trailer, probably 10k lbs. The Avalanche ran hot and had to be limped up hills. When I played with it on EFI live the knock sensors were all over the place and I could never tune them properly so it lived in the low octane map.

Like anything, tuning and sensors make a huge difference. If you went for a ride in my regal when it was N/A, you would absolutely change your tune. An animal for a "low compression" LS with only a cam and tuned by a moron.

 

[olds307 and 403]

Back in the day a coworker and I had identical 2001 5.3 powered 1500s. Mine was a ROCKET until I got a new 2006 2500HD. My coworkers truck was absolutely garbage, no power, never had the right gear and pretty much felt like a 4.3 V6.

I put 300k km on that truck and 160k km on the 06, 6.0. The 6.0 had 4.11 gears and drove like an old farm truck that was worn out. I don't think it's the motors, I think it's the way GM had then matched to the trans and the tuning.

I had a 2004 Avalanche with a 5.3 and when I moved in 2016 I did a trip with a way overloaded trailer, probably 10k lbs. The Avalanche ran hot and had to be limped up hills. When I played with it on EFI live the knock sensors were all over the place and I could never tune them properly so it lived in the low octane map.

Like anything, tuning and sensors make a huge difference. If you went for a ride in my regal when it was N/A, you would absolutely change your tune. An animal for a "low compression" LS with only a cam and tuned by a moron.

I have never disputed any of this, it has to be a tune issue, has to be. GM must be wildly optimistic and obviously only some are hitting the mark. That 6L dyno test was with Holley software, no doubt way better than a stock truck tune. I assumed the lousy low end tune was protecting the fragile 4L60-70E. The shift programming on the 6 spd was also garbage on the 11 with the 5.3, always hunting and never finding low rpm power. My only experience with these motors is the stock truck tune. When I borrowed my Inlaws 04 Avalanche, I ready was to be impressed, wow 295 hp and 335 ft/lbs. It had to be way more than the 307 headed Olds 350 in my 94 Z71, it wasn't where it counted as a truck. I was warned that the head light fell out and along with blowing fuses, it really disappointed me. The only bonus was better mileage. All rest were the same, disappointing. When I finally drove the two 17's, 5.3/8spd wow what a difference, they went like hell. I should have bought my BIL's 17 GMC for the 28K he sold it for, a steal in today's market. Way better mileage than my lousy Dakota.

 

[Clone TIE Pilot]

Probably the DBW controls, they are designed to learn to go "lazy" over time to conserve gas. Its one of the many reasons I hate DBW, the response is unpredictable because of the self learning feature .