350 vs 305?

[81Scottsdale520]

So my 350 is starting to die, as soon as i got home and put it in park i left it on cause i heard a clinging noise. i popped the hood thinking it was something metal hitting the body BUT it was inside the motor i took it for a lil drive up the street and when i press the brakes but when i press the gas then it doesnt rattle anymore. Letting it sit now til i figure out a decision. But anyways my uncle has a 305 that he is willing to sell at a good price, my question is my 350 worth fixing instead of swapping the 350 for a 305?

[andrewmp6]

If its just a driver the 305 if it runs right should be fine.If your looking for power rebuild the 350 and beef it up.

[INSIDIOUS '86]

Build the 350 and run the 305 while building the 350

Nothing wrong with a 305 just have too keep in mind that a 350 was built for power and the 305 built to save gas and do the same work as a 350. Both succeeded. A 305 is a good engine to have for a daily driver. In my build thread is a good example of a 305. You don't build them for power really.

[school boy]

use a mild cam in the 305 and you wont see much difference from the 350 unless it was tired.

[old Rusty C10]

305 is a horrid motor as far as power. I had one in my truck and swapped for the 350 and it was a whole lot better. I agree with Insidious throw the 305 in there if you need to have the truck running while you build or get a new 350.. and don't pay more than $100 for that 305 they are glorified boat anchors

[INSIDIOUS '86]

The le9 the H.O. And lb9 tpi 305 are all high comp piston and decent head 305s. A rv cam and an intake and carb with headers and exhaust and you can't tell a same setup 350 and 305 apart. I would disagree with your statement except the making power part. After about 300hp they start falling further and further away from a 305. All that means is one should stick to an engines purpose. A lot of 305s suffered the heavy emissions and horrible ign timing of the 80s a lot were replaced with lower performing 305s from auto stores. My friends target master 305 couldn't hold a candle to my old high mileage le9 305

[motornut]

I usally tear out the dying 305s from my cars,drop in 350s and run them
this 305 in my 79 runs really smooth,best i've seen in a while...
I've found the older folks look after them better,ones that buy them new too
over the years a lot of issues came back to the cams braking down from not changing the oil.

[kalbert]

You probably won't notice a difference as long as the 305 is in good condition. A worn out motor is a worn out motor, makes no difference how big it is. Both motors were built to meet a broad range of driving styles and a narrow set of emission requirements, so neither is going to set the world on fire. When new there would maybe have been a %15 difference in power, and probably not even %10 difference in fuel economy. Putting speed parts on is a different story... The same money spent on a 350 will net more return than on a 305, but that doesn't mean you can't do it. I equipped an LB9 Camaro with domed pistons, a moderate cam from TPIS who's part number escapes me, head work, and the usual bolt on stuff. It made just past the 300 mark on the engine dyno, and in the car got between 6 and 16 MPG depending on what you were expecting it to do. With drag radials it went high 13's. Take all that with a bag of softener salt though, I don't expect anyone to buy it. This is the Internet and everybody has a 305 Camaro that will "outrun my buddies Corvette" Point was all those parts on an auto equipped L98 instead would have been low 13's, similar economy, and would have been the difference between a good time and a great time.

I'd say swap in the 305 and drive it while you build the 350 to your liking.

[Smoke_Dog]

Just save the money and do the 5.3 or 6.0 mod!!!

[bdiamond]

I'll bet the flywheel is broke...

[kalbert]

Originally Posted by bdiamond

I'll bet the flywheel is broke...

That's a good bet. If I had a nickel for every time a guy came to me with a bad knock and a rattle that turned out to be only a cracked flex plate I'd have several nickles.

[Tdubbyount]

Originally Posted by kalbert

That's a good bet. If I had a nickel for every time a guy came to me with a bad knock and a rattle that turned out to be only a cracked flex plate I'd have several nickles.

Hahaha! I love it. Sounds like a very possible cause. Ive seen it a couple times myself. On the other hand, if its the motor, go with the 350 if you can. Your right foot will be much happier. Your wallet however, not so much.