383 Stroker or 6.0 LS??

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RoryH19

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Appreciate you sharing your experience. What type of mileage are you getting? Did you go with the 6L/4L80E setup?


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Np. Escalades have a 4l65e. They are stronger than a 4l60e but not as strong as the 4l80e. The other nice thing I had with my swap is both original driveshaft still worked.
Mileage I'd estimate at 18. I have a 3 in lift and 33x12.5 in tires.
I'll moving to 3.73 gears so it may change.
 

mcarlo86

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The longer stroke of a 383 probably would make more bottom end torque if you get the right cam and flat top pistons so you have decent compression. I would bet that a 454 bbc with the gear ratio you have mated to a 4L80E would be comparable economy to a built 383 and would tow better cross country. Someone earlier in this thread mentioned something about having to get his foot in a 6.0 when towing because they make their power at higher RPM's. I agree with that. I like the LS engines, but they do tend to make their peak torque at higher RPM's than a 383 would (or a 454). If you go with a 6.0 LS, I would suggest 4.11 gears with the tire size you have. Try to get you cruising RPM's near the peak torque RPM for the engine for best combination of fuel economy, towing ability, and driveability.
 

Craig Nedrow

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I tow quite a bit, using a 32h hp 355 sbc, a solid balanced motor. I now have a 454, cost to swap including motor was 2500.00. The BBC is much more fun to drive, all that torque, and when the four barrels kick in, it is a stead push. Have a few (3) Gen three motors. Very easy to maintain, have great power potential with just a small cam and a little tuning, they are tire shredders. My longtime friend has an LS3 (Gen lV) just as fast as my LS, but get better mpg with the VVT. Just to wet your appetite:
ZL1 run yesterday.
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a professionally built 400 sb with the right heads pistons cooling and cam would not fail and would provide the torque you need for towing. if you are mostly concerned about mileage, buy a late model truck
 

Rashad Baker

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a professionally built 400 sb with the right heads pistons cooling and cam would not fail and would provide the torque you need for towing. if you are mostly concerned about mileage, buy a late model truck
Not too concerned about about mileage, however I want to know what I can get


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illmanners

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Let's be honest here. If you are going to be towing 4K, an LS "may" get a tad better MPG, but expecting decent MPG from a gasoline engine when towing is like trying to make a silk purse out of a sows' ear. From a cost and ease of installation standpoint, with as few changes as possible, I'd vote the 383 with Vortec or Aluminum heads (the Chinese and Australian knock-offs on e-bay seem to be working well. I've used them both with no problems. ) Regardless of which engine you use, if you are going to tow anything, you WILL have a tranny temp gauge, cooler and run full synthetic fluid. Heat is what kills auto trans and when you tow, you build a lot of heat in the tranny. Synthetic tranny fluid lubricates and cools better and faster, promotes faster shifts.
 

Vbb199

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@eskimomann209 I'm right there with you. And everyone makes very good points. The one i know of and really what got me interested in the 8.1l was a guy screen named Dirtylarry over on the 67-72 forum. While most other things on that site are hit or miss at best. His build up was very thorough and detailed from start to end. I also really like the nv4500 and np205 setup he did.

http://67-72chevytrucks.com/vboard/showthread.php?t=298696

That being said. Its production stopped in 2009 and it was replaced with the 6.0. Probably for a reason decided by the bean counters and engineers at gm, as well as stricter emissions standards.

One thing I think we can all agree on, a 350, 383, 454, 5.3, 6.0, 8.1 really whatever engine to put into a square is a very fun choice to be stuck with.


Not sure if this ever materialized, but if so, wait until they hit the yards.. An engine "well over 8 liters"

https://www.google.com/amp/s/gmauth...g-new-engine-larger-than-new-6-6l-v8-l8t/amp/


I'd take that all damn day just because it's not 5.3, 6.0 or 6.2 lol
 

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Ricko1966

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I've seen this sh!t argued so many ways .If you run side by side comparisons of a 5.3 truck and a 5.7 vortec truck using EPA,Fuelly, Who ever you want you come up with mileage numbers that are almost identical and horsepower and torque differences that are not dramatic. The difference in HP and torque a few bolt ons would make up.And stupid simple to install a small block where a small block came out.No special anything needed. If I were going to run the 700r4 I would Install a drain plug drain and fill often. Filter every 30k or so. For stupid simple and most value for your dollar stay sbc.

Just for fun I just went to edmunds and fuelly compared a 97 silverado 5.7 and a 2001 silverado 5.3 hp the 5.3 wins by 30 hp. Torque the small block wins by 5 lbs, the sbc torque was at 2800rpm the 5.3 was at 4000 rpm.mpg was pretty much identical.Torque pulls trailers, horsepower sells trucks.
 
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Ricko1966

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The MPG you're angling to get is all relative to tire size and gear ratio.

I've had people argue, but I've gotten 20-22 mpg on a 3.08 geared burban with stock tire size.
If you're angling to get ok MPG, just don't go running 4.56's on a small tire or some weird ****.

There's a nice balance on ratio and tire size with towing.

Tell me your whole package I would be so happy to have a 20/22 mpg full size truck.
 

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383!

383!

383!


I have a 2008 GMC 2500 W/T with a 6.0L, and while it is an awesome engine and the truck is great at getting **** done, it is so NOT a square. Nothing about it would feel normal being under the hood of a low tech 70s-80s vehicle. The sound of the mini starter alone is just wrong. IMO LS engines look out of place under the hood with the plastic cover and all the wires, not to mention the electrical nightmare that is OBD2- it will forever be a needy pain in the ass. Sensors, coils, computers, etc. You can fix a SBC with a hammer and a pair of channel locks.

You have a simple dependable bulletproof truck, keep it that way. If you're worried about towing get a set of gears and a trans cooler. Not expensive, and readily available. If you want more power, by all means I get it, go ahead and use that 383, or even a BBC.

But LS swaps into squares drive me nuts. Might as well just buy a newer truck at that point. Yuck, no thanks
 
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Vbb199

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Tell me your whole package I would be so happy to have a 20/22 mpg full size truck.


Was my old burb.
100% stock, absolutely no mods.
90 Throttle body injected 350, 700r4, 3.08 rear gear and whatever factory tire size was.
It was incredibly dinky tires on a 15" wheel
 

mcarlo86

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Was my old burb.
100% stock, absolutely no mods.
90 Throttle body injected 350, 700r4, 3.08 rear gear and whatever factory tire size was.
It was incredibly dinky tires on a 15" wheel

Probably was 235 75R 15's. They are about a 29" tire I think.
 

RecklessWOT

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Probably was 235 75R 15's. They are about a 29" tire I think.
Haha, yep. That's what size the bald goodyear wranglers were on my '87 Burb when I got it. Thing looked like a damn station wagon, running boards were like a few inches off the ground.
 

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