Can't decide what to do. Suggestions? Thoughts?

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thedog52

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Reece
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Hello all. I have a 1991 Suburban 2500. It has the 350 TBI, and 4L80. It is 4X4. It is dead nuts reliable. I drove it to Florida lasy year (over 1k miles one way for me) and it routinely goes to the lake, hunting/camping trips, etc. I use this truck for everything. I've pulled a tri toon with it. It didnt like it, but it pulled it. Here lately, I've noticed the power just seems gone. Its happened over time. It is so gutless it isnt fun to even drive anymore. Starts and runs fine, just zero power. The odometer broke at 180k. I have no idea how many miles are on her. I would be willing to bet atleast 250k. I am considering pulling the tired 350 out, and going LS. I am also thinking about doing a vortec 350, just to make things simple. Cost (from what I gathered) would be very close. I just dont know that I care to go through the frustration of making an LS work. This suburban has working AC, and it looks like I'd likely have to figure out a new mount for that, plus whatever else pops up. I really don't want to have the thing sitting for a long period of time trying to work through all the little things. That is why I am considering the vortec 350. I know I'd need a different intake, and the computer would have to be tuned. That stuff doesnt bother me. I hate having a vehicle down for a long period.

From what I can find online, a rebuilt vortec is around $2800. Intake is like $500, and computer chip is $500. A 6.0 complete in my area fresh from a junkyard is $1700, then I'd need the harness worked, PCM, serpentine setup, pedal, and whatever else pops up. From my estimation, if I scrounge around, I'd be looking at $4-$5k, plus the time required to get the little stuff working.

This vehicle is used for work and play. It is not a hot rod. I dont care if it makes 500hp. Yeah it would be awesome to have a boosted 6.0 animal, but I don't really need that. I just want something that can get up to speed quickly, yank a trailer, and be reliable. What do you guys think?
 

Ricko1966

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SQ HAF KRU

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You might even consider a fresh long block, carb intake, with a Holley or FItech throttle body EFI, they work really well ....run a little better than a carb, you might even see an increase in your MPGs
 

Grit dog

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I like @Ricko1966 idea the best.
Maintain the ease of not hassling with all the LS changes. And have you a good pulling motor that should be as reliable as any small block.
Seems like that fits your priorities the best.
 

gmbellew

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Ricko1966

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^^^^ looks like,and probably is a stock 5.7 TBI engine with a lt1 350 roller cam. This would be a dirt cheap build if you had a usable TBI 350 core.
 
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thedog52

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I appreciate all your responses. I did some research, I believe the burb has either 3.64 or 3.73 rear gear, which means its chugging along at 70mph around 1900 rpm. No wonder it cant tow worth crap. Im now considering changing out gears first and see what that does
 

Ricko1966

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I appreciate all your responses. I did some research, I believe the burb has either 3.64 or 3.73 rear gear, which means its chugging along at 70mph around 1900 rpm. No wonder it cant tow worth crap. Im now considering changing out gears first and see what that does
Run compression and check vacuum readings,I'd bet your engine is pretty worn. What tires are on it?
 

thedog52

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They are 32" tall tires. Engine doesnt burn a drop of oil, which makes me think maybe it isnt so bad? Heads could be garbage though. Ive thought about just throwing some vortec heads on there and tuning it.
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Ricko1966

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They are 32" tall tires. Engine doesnt burn a drop of oil, which makes me think maybe it isnt so bad? Heads could be garbage though. Ive thought about just throwing some vortec heads on there and tuning it.
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Are you towing in O.D.? Just a pair of vortec heads isn't going to be enough difference to warrant the cost,the effort,and the problems. People bag on the swirl port heads,but they do their job as intended,low end grunt and mpg.
 

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