5.7 vortec vs 5.3l or 6.0 swap

[L31MaxExpress]

Nope, T56 and dinky 10 bolt. How much more do you think you are making than a built 6.0?

Between 1,000 and 3,500 about 60+ TQ over a 6.0L.

T56 and a dinky 7.5 lose about 15%. A 4L60E and 7.5 eat about 18%. A 4L60E with an 8.5 and a clutch fan eat about 22%.

Your LS1 is atleast 70 ft/lbs off this 383.

Remembering drivetrain loss builds as RPM builds. That 15% at peak hp probably drops to about 11-12% at peak torque.

 

[90west]

First off I want to say thank you to all of the guys that actually have first hand experience on this subject it really wears me out when you have a question and ppl reply with misinformation they found second hand.
Secondly as of right now I’m really leaning towards just bumping up the 350 just because I’ve done the “ls swap” on a jeep tj I had and it was great, problem is it can end up nickel and dimeing you to death with all of the little things you forget you need till your already into the swap then our truck is sitting waiting on parts to be delivered instead of making money but that’s just my opinion

 

[L31MaxExpress]

A stock LQ4 that makes 320 hp and 380 tq is lucky to dyno 240 hp and 280 tq in a 2500 truck with an 80E and 10.5FF. I have seen one do a bit better with a 9.5 semif float.

Stone stock 242 hp and 280 tq.

https://www.webservice99.com/hypertech/PerformanceGraphs/gm/6_0L_2003_2007_GM_Classic_CK1500_2500_3500_32500.pdf

 

[0xDEADBEEF]

I thought we moved past talking about stock ...

LOL @ 1000 rpm. Even turbo diesels don't drive around at 1000 rpm.

 

[L31MaxExpress]

I thought we moved past talking about stock ...

LOL @ 1000 rpm. Even turbo diesels don't drive around at 1000 rpm.

I don't drag it down to 1,000 rpm, but after tuning it I did alter my converter settings to drag it down to 1,200 rpm rather than the 1,500 rpm I had it at. I found 28 ft/lbs more at 1,800 rpm during the tuning session. Gas is getting more expensive and keeping that 2,800 rpm converter locked when I do not need the torque multiplication only helps mpg.

My old 5.13 geared 10.5 has a leaking axle shaft and worn spider gears and needs the drum brakes rebuilt, for a temporary measure, I swapped a 3.73 G80 I got local for $250 in its place. Will rebuild the other 10.5 later and swap it to disc brakes along with a powertrax locker so that it is fresh and ready to go. I may tame back the gears to a 4.10 or 4.56 tops as the 383 has enough grunt that 5.13s are overkill even dragging my travel trailer. At 40 mph around town I roll along in overdrive at 1,200 rpm now. On the highway I am at 2,100 rpm at 70 and 2,400 rpm at 80. Running around DFW in traffic at the posted 60 mph the 28 ft/lbs increase is noticeable as I am right at 1,800 at 60. LT275/70R16 tires. ~3,500 rpm is an important number to me because that is a little over peak torque and I tend to modulate the accelerator at a point to where my transmission shifts around peak torque when I am accelerating. Rarely a need to floor it in 99.5% of my normal driving.