Best LS / LT - GM V8 for Daily Driver - Decent MPG?

wesinls

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So my 2018 Colorado commuter truck got totaled and with the 25k I've decided to buy a vehicle I've always wanted...2 door Tahoe and have it be my daily driver. - yep dumd as fuk idea, I know,

But the kicker is, that not everyone knows, is they actually made a few of these in a Diesel...which for me in California, means no smog (1997 and older = no smog).  What's also nice is that the diesel Tahoe's (at least in the 1997 model - other years maybe too?) comes with a 4L80 - so a nice strong trans - the diesel's also up the tow rating from 5k to 7k.... Anyway - random info I geek out on and figure I'd share.

I bought the one below a few days ago ...decent price given how clean it is and the rarity of it - and for close to or less what I got for my Colorado I'll have commuter car that should go up in value.

So - to get to the point of my post:

What LS or LT engine would make sense for a commuter in this thing - nothing too crazy but also not a waste of time and money? An LS1 from and 2000ish vette is around 3k off ebay with 80ish k miles and seems like a good option?...a 4.8 or 5 .3 out of a Silverado ?  I'm not too up to speed on the LT engines...been reading about them....seems like they are more $ and newer? 6.0 / LS2 maybe...idk.

No smog gear needed will make things a lot easier.

I'd like to stick with something a Holley Terminator can support as I'm familiar with them - and Dakota digital sells a dash for the Tahoe's which will allow me to get gauges up easily.

Any recommendations? 

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WOW.  Super cool concept.  What is your MPG goal? What MPG does it get with the diesel?  I did a quick google search and it weight 6000+ lbs.  LS engines are not MPG gods, a '05 2wd single cab with a 4.8 / 5 speed manual only averaged 15.  I think the diesel cool factor outweighs the LS.

 
WOW.  Super cool concept.  What is your MPG goal? What MPG does it get with the diesel?  I did a quick google search and it weight 6000+ lbs.  LS engines are not MPG gods, a '05 2wd single cab with a 4.8 / 5 speed manual only averaged 15.  I think the diesel cool factor outweighs the LS.
Around 16 from what I've read so far is what it gets now....I haven't driven it yet - I bought it from Texas and waiting for UShip bids...or might fly and drive it home.

Around the same or better would be cool....I drive 30 miles one way to work 4 days a week - mostly highway.

 
^ This? Major HP and torque can be made with a diesel. 

 
And with the right gearing, mileage... 

 
I don't know if the state will ever require some sort of pre-97 smog but that would be my concern considering how costly that motor swap could get. You would need not only a motor but what about the trans? Is that trans plug and play with an LS or does it use shift logic calibrated for the low revving and torquey 6.5? Rear end gears? Wouldn't they need to be changed out for something happier going down the road at LS RPMs? The 6.5 has plenty of aftermarket for it but will make a very loud commuter I would imagine. 

 
So you went from a bumper and tailgate repair and pocketing $15k on a 6 year old Colorado (but decided not to do it because it was too much of a hassle) to LS swapping a 25 year old diesel Tahoe (that normally comes with an LS anyway) to avoid smog.

Seems logical to me.

Peas

 
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So you went from a bumper and tailgate repair and pocketing $15k on a 6 year old Colorado (but decided not to do it because it was too much of a hassle) to LS swapping a 25 year old diesel Tahoe (that normally comes with an LS anyway) to avoid smog.

Seems logical to me.

Peas
Look, us offroad types may not be the sharpest tool in the shed, but man we got Ideas that won't stop......plus my dad was a TV repair man.....awesome set of tools!

 
Are you sure about the 1997 no smog?

May be a different situation but I registered a 1987 Porsche and had to have it smogged. Maybe the transfer is why but I was told Ill have to do it every 2 years

 
Are you sure about the 1997 no smog?

May be a different situation but I registered a 1987 Porsche and had to have it smogged. Maybe the transfer is why but I was told Ill have to do it every 2 years
Yes:

Your vehicle does not need a smog inspection if your:

  • Gasoline-powered vehicle is a 1975 year model or older (This includes motorcycles and trailers.)
  • Diesel-powered vehicle is a 1997 and older year model OR with a Gross Vehicle Weight of more than 14,000 pounds.

Smog Inspections - California DMV

 
So you went from a bumper and tailgate repair and pocketing $15k on a 6 year old Colorado (but decided not to do it because it was too much of a hassle) to LS swapping a 25 year old diesel Tahoe (that normally comes with an LS anyway) to avoid smog.

Seems logical to me.

Peas
1997 Tahoe didn't come with an LS...but thanks for your great input buddy.

 
I don't know if the state will ever require some sort of pre-97 smog but that would be my concern considering how costly that motor swap could get. You would need not only a motor but what about the trans? Is that trans plug and play with an LS or does it use shift logic calibrated for the low revving and torquey 6.5? Rear end gears? Wouldn't they need to be changed out for something happier going down the road at LS RPMs? The 6.5 has plenty of aftermarket for it but will make a very loud commuter I would imagine. 
4L80 is in it now - .LS engines bolt right up to them. and gearing should be 3:73 in the rear....not sure yet. The Holley Terminator max takes care of the rest of the settings...shift points, etc.

Price for swap 
3500 for engine,  1000 for exhaust, 2500 for Holley - another 1000 or so for misc. stuff, engine mounts, fuel pump, fuel lines, etc.....so around 7k.  Right at the 25k of my budget is the hope.

I'm also not ditching the idea of keeping the diesel...I know nothing abiout them but plan to keep it for a while and learn about them...maybe I'll leave it, IDK.

Pipe dream of why I've always wanted one of these....I like the body style, and a someday a built LS3 on an RCD lift with 33's would be a fun toy, but for now a commuter. 

 
A 2 door is rare enough but the diesel would make everyone do a doubletake. I forgot to mention suspension. Springs and shocks may be special to the diesel. Again, I don't know. Sounds like an awful fun project.

 
1997 Tahoe didn't come with an LS...but thanks for your great input buddy.
Yes I see. I just went back and reread your original post. I do know that pre 2000 tahoes had vortecs. Still seems like a huge waste of time and money to build something so mediocre and also ruin a rare diesel (even though it's a 6.5) tahoe just to avoid an emissions test (even though you shouldn't have any trouble passing one) for a commuter vehicle when you could have had a much later model commuter and pocketed a fair amount of cash. I have a hard time subscribing to the idea that a 97 Tahoe will go up in value regardless of what powerplant someone put in it.

Maybe use the extra $15k from insurance to buy the 2 door Tahoe you want and fix/keep the Colorado for a commuter 

Peas

 
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Yes I see. I just went back and reread your original post. I do know that pre 2000 tahoes had vortecs. Still seems like a huge waste of time and money to build something so mediocre and also ruin a rare diesel (even though it's a 6.5) tahoe just to avoid an emissions test (even though you shouldn't have any trouble passing one) for a commuter vehicle when you could have had a much later model commuter and pocketed a fair amount of cash. I have a hard time subscribing to the idea that a 97 Tahoe will go up in value regardless of what powerplant someone put in it.

Maybe use the extra $15k from insurance to buy the 2 door Tahoe you want and fix/keep the Colorado for a commuter 

Peas
You'd be surprised what they are going for - and they keep going up....If I swap out the engine, I'll keep everything so that I can put it back to stock...square body blazer going up, as are the Tahoe's.

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