305 Is a Turd Correct?

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Boots97

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In my opinion:

4.3<305<350

That being said, because your 305 short block is still good, I'd mod it the same way you'd mod a 350. People have already posted great replies and you can still do a lot with a 305. If you'd REALLY wanted a 350, I'd rather just sell the truck and buy a truck that came with a 350 from the factory. Plenty of GMT400s with 350s around to where I wouldn't swap one in unless your current engine was FUBAR.

As someone who daily drives a Vortec 350, while it's nice to have the power and it's what I originally wanted, part of me wishes I would've bought a truck with a 305. I don't tow and only occasionally haul stuff so the power wasn't 100% worth it and I never get anything better than 17 mpg. It's partially why I plan on buying my parent's 2004 Honda Civic.
 

Komet

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I'd roll one in a stock application, but I don't see the point in building one when you can go get L31s out of the yard.
 

L31MaxExpress

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Personally starting with a 305, most of those were roller cam provisioned engines. If the short block was in solid shape, I would bolt parts to it that can transfer to a 350 or 383 later. It is easy to liven one up with long tube headers, decent exhaust and parhaps a pair of Etec170 heads. Learn to either tune the TBI system while the engine is stock or figure out a better EFI setup to run.
 

CumminsFever

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A good breathing 305 is a tolerable daily driver. In my dad's shop, we had a customer bring a '90 gmt400 in for an engine replacement. It had a 305. Junkyard gave us a 305 from a 94 cop car. That was equipped with a roller cam. It was smooth, quiet, and could get a small squawk from the tires just by smashing the go pedal. It was a rclb 4x4,got 20mpg highway driving.
The 305 isn't a monster, but it's a tolerable daily driver. I agree with the idea of bolting on parts that could later be used on a 350 or 383. Tune it and run it. As previously mentioned, the 305 has been known to go many miles, even when beat on.
 

DerekTheGreat

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I've got a 305 TBI in my Firebird, the same turd they put in the trucks, just with a factory roller cam. It was a reliable turd that couldn't get out of it's own way or smoke a tire on dry concrete. Early 20's me threw cylinder heads at it, Performer TBI intake, 3.23's + limited slip and an MSD ignition system. It gets 21.xx mpg instead of 24.xx on the highway but beats factory 350 TPI cars and happily roasts the tires from a stop. Compared to my '89 K1500, it's a lot of fun and has plenty of zip. It'll stay until it implodes.
 

l1lartur0

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Yes, a 305 is a turd. I owned 1 in my life, and will never own another 1. Bad MPGs and no power.
The 305 in my family's 1981 Olds Cutlass LS was a knocking, sputtering, hateful engine. Had around 50k miles on it before it gave up the ghost on a trip back from Galveston just south of Waco in the mid-80s.

The current truck has a 305 Vortec, and *knock on wood* it's been a reliable little powerplant. Truck has over 400k miles notched up - though a possible caveat is that the drivetrain could very well been rebuilt under the administration of one of its previous owners. Nevertheless, it does its job well for what I need from it: as a daily driver that ocassionally hauls light loads.
 

kennythewelder

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The 350, was built with performance in mind, in the late 1960s. Then, it was detuned for MPGs. The 305 was GMs attempt to get better MPGs out of the small block. By the time GM made the Vortec engines, things had evolved to where GM took the 305, to a decent level of performance for what it is. Personally, I have had several 350s and have 2 of them rite now. 1 in my 97 Silverado, and 1 in my 79 Corvette. The 350, was never designed for MPGs. My truck is at about 325 HP, at the crank. My Vette, is at about 475 HP, at the crank, give or take. In town, neither one, gets more than about 10 MPGs. The Vette is worse, of course, but I didn't get it for the MPGs. In 1999, I bought a 1993, WT, with a 4.3L. That was a grate truck. Decent MPHs, and decent power, after I did a performance upgrade on the exhaust. I let the 93 go, when the trans gave up at about 225,000 miles. My 97, Silverados rear end gave out at about 250,000 miles. Less than 2 weeks after I rebuilt it, with 373s, and an Eaton true track, the trans also gave up. I had it performance rebuilt with a HD master rebuild kit, Corvette servo's, and a shift kit. For a Dailey, get around truck, that doesn't haul a lot, I would have another 4.3L in a heart beat. IMO, the 4.3L is what GM was looking for, when they first built the 305, all those years ago. I bought my 97, in 2002, for my wife. When the 93s trans, bit the dust, I took the 97 from my wife, and bought her another vehicle. Not a GM, and not a truck. I sometimes think, I should sale my truck, and get a single cab, with a 4.3, but I have so much work in my 97, I hate to let it go.
 
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