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Discussion Starter · #1 ·
So ive been doing some resarch on an ls swap in my truck and a buddy of mine said dont waste the time or money just go big block simpler and proven. I want fuel injection either way and reliabilly is a big factor as well.
This will go in my 77 k10 with 1tons and 38in tall tires and soon 4l80e trans i really dont want a trailer queen i like driving my truck everywhere. If i go ls it will be an lq9 maybe with a small turbo any opinions would be great thx guys
 

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I have a bbc and it will be the last one I own.

Sure they are simple and make good power. But they are heavy, gas sucking hogs. Even after 10 years of driving my 454, I still get surprised how much fuel it can drink.

You can make the same power with a LS and get twice the mpg. And LS engines liter the salvage yards. Once you make the swap, I'm sure your friend will see the light.

A 5.3 liter LS with a pair of T3's from the first generation 300zx turbo or a 280zx will work very well. I get these turbos all day from U-Pull-It salvage yard for around 60.00. A stock super 60 T3 is good for 300hp, so two should be good for 600.

As you know, 38" require lots of gears, right?
 

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Discussion Starter · #5 ·
Well its street driven and here in AZ there is pretty much everything to do offroad wise the truck will be taken everywhere was just mainly concerned with street manners and simplicity. As for gas mileage what's the best you guys think I could get? Before the swap to one tons and 38s with 35s. 373s I was getting like 12 city and I never calculated highway and that was with a rebuilt 355 stock cam headers intake and a poorly tuned 1406
 

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in a 1 ton.. no streetmannered ls will make the lowend torque that a bbc can..
not even the 6.2ltr
talk to people that use the ls daily to tow.. or loaded down.. and see what mpg they are getting..
the 1 ton drivetrain takes power to turn it.. torque is your friend...
I'd get a duramax before I'd drop a ls in a 1 ton if I was working it..
the low end torque of a big block with the loaded mpg of a smallblock
 

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check out pirate 4x4 for ls and other info. also ls1wiringharness.com for wiring harness info, welders series for engine mount adapters and other mounts etc, nook and tranny lsx info for general info etc. there isa write up on an ls swap in one if the issues of truckin web. they put a 6.0l ls in an 82 blazer. should be roughly the same scenario as what you have there. just google it. lots of pics in the article.
 

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SFC equals specific fuel consumption,,,
An engine requires an amount of fuel and air to make a certain amount of power. A block contributes very little to the fuel consumption other than the adverse effect of weight.
For 4x4 use you need usable torque more than peak horse power..Gearing can make up for torque.This can go in circles all day,so,lets determine what you need for power,then determine how to get there?
A long stroke LS engine can make plenty of power and torque in a smaller package.
any modern engine with good fuel management and ignition control will make more power and burn less fuel than older technologies,especially carbs.
The LS engine line has a lot of optional and after market equipment available.You can stroke the LS engine for torque.If you need a really big engine then build a 540 BB or bigger?
What do you need? How much fuel is too much?
 

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Is cost a factor at all? Swapping in a 6.0L and 6 speed trans will probably cost you about 2-3 grand for a simple swap. Building a 454 bbc is going to cost you more than that and then you have to install it. the LS is cheaper.

If you need big torque are you open to a supercharger or turbo? this will add the same amount to either engine and will make either one capable of more power than you need.

The LS is more efficent and will return better mileage. I have a extcab ext bed 09 2500HD and if I'm easy on it I get low 20's unloaded and about 18-19mpg loaded. Most BBC trucks can't touch that, and most diesels do better than that.

If you're planning to tow a lot of weight for many many miles (100,000+) then a diesel is really the way to go. If you're just towing 20% of the time (like I do) an LS is the way to go. If you need more torque for really heavy loads then I'd go with the steepest gear you can and/or a turbo.

Something else to keep in mind is that for durability using good oil and not lugging the engine can go a LONG way. With those tires are trans I'd go with a 4.56 gear at a MINIMUM. Going with a steeper gear will have little effect on mileage but it will help your engine last a lot longer.
 

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My dad had a bbc in his truck 2006 silverado 8.1 liter. I had the 5.3 Ls in my tahoe. I got about 15 mpg in a big heavy truck in normal city light-to-light driving, and 24+ on the highway. My dad's truck got... wait for it... a whopping 9MPG HIGHWAY. Yikes.
LS > big block any day of the week.
 

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Discussion Starter · #11 ·
Thx guys towing is not rarely gonna happen maybe quads but I was planning on turboing the ls if went thought route and I don't see the real need for a diesel swap so Turbo lq9 it thx guys
 

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So ive been doing some resarch on an ls swap in my truck and a buddy of mine said dont waste the time or money just go big block simpler and proven. I want fuel injection either way and reliabilly is a big factor as well.
This will go in my 77 k10 with 1tons and 38in tall tires and soon 4l80e trans i really dont want a trailer queen i like driving my truck everywhere. If i go ls it will be an lq9 maybe with a small turbo any opinions would be great thx guys
What's the reason for the 4L80E trans?
 

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Thx guys towing is not rarely gonna happen maybe quads but I was planning on turboing the ls if went thought route and I don't see the real need for a diesel swap so Turbo lq9 it thx guys
A 6.0 with a cam, headwork, and normal bolt ons will make plenty of power to move your truck. No need for a turbo
 

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I personally would say go the diesel route. If you can find a later model duramax then that is what I would use. I have an ext cab short bed 2500HD 4x4 with a LQ9 6.0L and I get horrible gas milage. it's about 14 on the highway and about 9 city. Over all I average right around 11.5mpg. I do have slightly larger tires on the truck and the truck also has the 4.10 gear option instead of the 3.73 standard gear option. I do however love the truck and the engine. it would suprise most people with how quick they are.

if you go the 6.0L route then I would suggest stroking it to a 408. the only problem then is that you will have upwards of what you would have had into a BBC but yet still not have the power of a BBC. Again this is why I say you should look into the Duramax.

here are some numbers from the Duramax engine.
01-04' 6.6L LB7 which for the early years had 235hp/500tq but for the later years made 300hp/520tq

05-06' LLY which had 310hp/520tq in 05' and 310hp/605tq in 06'

late 06-07' LBZ which had 360hp/650tq

if you were able to take the emission equipment off of these and run a free flowing exhuast with a tune upgrade It should be had at all to make 450hp and 750tq and still average 20mpg. You'll spend a bit more finding the engine but I think it would be well worth it.
 

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I personally would say go the diesel route. If you can find a later model duramax then that is what I would use.

here are some numbers from the Duramax engine.
01-04' 6.6L LB7 which for the early years had 235hp/500tq but for the later years made 300hp/520tq

05-06' LLY which had 310hp/520tq in 05' and 310hp/605tq in 06'

late 06-07' LBZ which had 360hp/650tq

if you were able to take the emission equipment off of these and run a free flowing exhuast with a tune upgrade It should be had at all to make 450hp and 750tq and still average 20mpg. You'll spend a bit more finding the engine but I think it would be well worth it.
This makes sense to me.
 

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I must have missed the op mentioning diesel.
I totally support going diesel too. Its pretty involved since there is a lot to change, but the benefits are huge. Despite how much I love the duramax, the 12v or early 24v cummins would be cheaper to swap in. If you can get your hands on a duramax then go for that, but the cummins will be cheaper normally.

Either way, diesel would be an awesome investment especially if you plan to drive the truck a lot.
 

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Discussion Starter · #18 ·
I would love a diesel in my truck its just I have tons of help with the ls I have a few friends running them in camaros and blazers and wouldn't the cost be alot more then either a stout big block or decent ls
 

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I would love a diesel in my truck its just I have tons of help with the ls I have a few friends running them in camaros and blazers and wouldn't the cost be alot more then either a stout big block or decent ls
It would cost a little more initially but with the money you'll save on gas the diesel will end up costing less
 
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