Is "all original" worth keeping a 305?

[BaseModel]

Hey guys! I purchased a (total CRAP) '86 GMC that was promised to be reliable and get me to Texas with no issues, but which is yet again sitting in front of my Mechanic's to chase a wire issue, after already having to replace the starter, battery, AND carb. Really, it makes me sick to think about.

In the mean time, to get me down to Fort Hood before my PCS leave ends, I found a super straight '84 K-10 Scottsdale for a song. Runs good... smokes like it's getting paid to do it, though. I definitely have a valve cover leak on the passenger side and most likely a good bit of blow-by as well. Fixed the breather tube slipping off to stop the regurgitated oil from seeping onto the headers for the time being, but this truck was bought with the intent on getting me to Texas and around post until my car makes it back from Germany, at which point it will be a really awesome project. This leads me to my question:

This '84 is all original. Totally. When rebuilding her, is it worth keeping the 305 (as opposed to going with a crate or rebuilt 350) due to it being the original equipment? I know 305's won't ever make as much power as 350's, dollar for dollar, but you know what? I don't need a powerhouse. I need a good, reliable truck. That's it. But really is it worth keeping the 305 and rebuilding her for collector value?

[andrewmp6]

Depends if its short bed or long bed and how stock the truck is.

[BaseModel]

Long bed, it's completely stock right now. i would be making slight tweaks here and there, though.

[andrewmp6]

To me its a mass production truck do whatever you want.Some others will say leave it as stock as you can.

[Man With A Gun]

If you're trying to sell the truck to somebody, it will be just as easy to find someone who'd rather have a NOM 350 as someone who prefers the original 305.

Get what you want IMO.

[RandyP]

You guys watch way too much Barrett Jackson... numbers matching square body, LOL.

[N2TRUX]

Average Joe consumer would prefer that the 305 was replaced with a 350.

[68c10owner]

I`m replacing the 305 in my 85 GMC SWB with a crate 350 as soon as I can afford it. I was told it probably isnt the original engine anyway but not really worried about numbers matching on a truck unless it was a original SWB 454 truck like my 75 GMC was.

[MalibuSSwagon]

I'd just swap it to whatever you want. My 305 did the job and was actually in good shape when I removed it to put in a 5.3L. Really unless you have a low production edition like a sport or something, original is not a big deal. I thought mine was rare with a factory installed SM465 but it turns out due to clever marketing that many C10s left the factory with a "Muncie" 4 speed

[slotard]

I'd prefer a better engine. You might consider an ps swap although they are more work. The main reason I'm not considering efi on my engine is I want overdrive. An lq4/4l60e might work well if you aren't doing a lot of heavy towing.

[cadillac_al]

Originally Posted by 68c10owner

I`m replacing the 305 in my 85 GMC SWB with a crate 350 as soon as I can afford it. I was told it probably isnt the original engine anyway but not really worried about numbers matching on a truck unless it was a original SWB 454 truck like my 75 GMC was.

Did those '75 truck 454's have peanut port heads on them? I have heard much conflicting info on when the peanut ports were first used. I think I have it nailed down to 75 or 76. I am looking at a 75 truck 454 that is a few miles away from me so I can't pull a valve cover to know for sure. TIA and sorry for the hijack.

[jjmorrse]

Caution, long-winded opinion by individual lacking any objective unique expertise in this matter follows:
That type of question depends upon your point of view. At one time, a 67 Camaro was a collector's item, but a 71 wasn't. Some people now are claiming that late 70's personal luxury coupes of the malaise era are becoming classics. Eventually, any well preserved original vehicle will generally be worth more than a modified one. A classic requires two things: scarcity and desirability. It is common for sellers to overlook one or the other when pricing their vehicle for sale. Often somebody will buy anyway. Except in the case of customizers who sideline drawing demented rats holding onto out of scale shifters, originality always ages better than customization. In the early 90s, everyone wanted a shaved pepto bismol pink or lime green pro street style vehicle, and the ideal mini-truck had a neon palm tree in the back window, and an off kilter sunken license plate. The 90s were not unique in this context: two words- Corvette Summer. Once upon a time, a person couldn't give away a station wagon, now they are a desirable body style.
Although hard to believe today, a 305 chevy truck will someday be rare. If it is also desirable, it will be monetarily valuable. If someone wants to be the curator of that particular piece of history for the future, then by all means, keep it original. If they want a 350, then that does not make them a bad person. It might make sense to see what it costs to get a rebuild on the 305, compare it to a 350. If you have a kid, choose the cheaper one and put it in their college fund. If you tow, a 350 is better. If you TOW, a 454 or diesel is better, but then expect to upgrade parts downstream. In terms of ensuring that your truck is a rare original, the best odds of ensuring that is rare is to keep the stock ride height. If a truck these days is not 2 inches lower, it is 3 inches higher.

[Dead Parrot]

This 2 cents assumes your cash supply is an issue.

If you have a real desire to keep the 84 as original as possible for the future, pick up a cheap roll around engine storage stand. Pull the 305, prep it for long term storage and put on the storage stand. Put in a new 350/260hp crate motor. Budget for new accessories as well. Starter, PS pump, alternator etc. Check out the several threads on this forum for camshaft, intake and carb recommendations for a mild upgrade in performance. Unless you do most of the rebuild work yourself, the cost of overhauling the 305 will likely exceed the cost of the new crate 350. And you will still have a used 305.

Then if in the future, a parts original 84 becomes valuable, you can do an as time and cash available rebuild on the 305.

[Liberty]

Didn't the 305 like to chew through bearings?

I have never heard much good about those Engines. In today's world folks want the 350. That being said, there's no reason you can't keep the 305 in storage and plop a 350 in there.

[N2TRUX]

Originally Posted by Liberty

Didn't the 305 like to chew through bearings?

I have never heard much good about those Engines. In today's world folks want the 350. That being said, there's no reason you can't keep the 305 in storage and plop a 350 in there.

Myth and internet rumor. There is nothing "wrong" with a 305. The 350 just happens to have more cubic inches, and as the saying goes "There is no replacement for displacement"

[MikeB]

If the 305 needs only minor repairs, keep it. But if compression is low or it's smoking like crazy, a new GM base 350 crate engine is probably cheaper than properly rebuilding a 305.

Here's a new 73-85 truck engine:
https://chevroletperformanceparts.co...85-most-models

And a 87-95 engine:
https://chevroletperformanceparts.co...95-1500-trucks

I'm not sure which one would cover 1986. Somewhere around 86-87, half-ton pickups got engines with one-piece main seals, and some got roller cams.

[Tom]

Nobody cares about all original 305's. Junk it.

[Malo83]

My 305 runs great, let's get real, it's a truck, I look for dependability not speed, besides it being a Cali truck, not much you can do to them, the new E-Rod Ls3 6.2 is the only legal engine swap that;s CARB approved, and since i'm an Old Skool cruiser i'll hang on to my boat anchor 305.

[slotard]

Originally Posted by Malo83

My 305 runs great, let's get real, it's a truck, I look for dependability not speed, besides it being a Cali truck, not much you can do to them, the new E-Rod Ls3 6.2 is the only legal engine swap that;s CARB approved, and since i'm an Old Skool cruiser i'll hang on to my boat anchor 305.

There are plenty of other legal swaps but swapping all the smog equipment is required. Not so much fun.

While swapping a 350 might not be legal, are they really going to check? I'd be surprised. You could almost certainly get away with a 350 (or a 383, or any smallblock that isn't obviously non-stock) as long as you kept heads that look about like stock ones, etc. Or am I missing something? My truck is a '73 so I don't have to smog it, but on smog checks on other vehicles I don't think they've looked at block numbers.

[68c10owner]

Originally Posted by slotard

There are plenty of other legal swaps but swapping all the smog equipment is required. Not so much fun.

While swapping a 350 might not be legal, are they really going to check? I'd be surprised. You could almost certainly get away with a 350 (or a 383, or any smallblock that isn't obviously non-stock) as long as you kept heads that look about like stock ones, etc. Or am I missing something? My truck is a '73 so I don't have to smog it, but on smog checks on other vehicles I don't think they've looked at block numbers.

Swapping to a 350 would be perfectly legal as it was a optional engine in these trucks. Not sure of smog equipment changed from 305-350`s though. I`m going to register mine in a different county that doesnt require biannual inspections. Just so happens we have a friend with a vacation home that I can use for the address.

I have also considered swapping in a TBI 350 as it would still be OBD1 which I already have and would have less smog stuff than my current 305.

[68c10owner]

Originally Posted by cadillac_al

Did those '75 truck 454's have peanut port heads on them? I have heard much conflicting info on when the peanut ports were first used. I think I have it nailed down to 75 or 76. I am looking at a 75 truck 454 that is a few miles away from me so I can't pull a valve cover to know for sure. TIA and sorry for the hijack.

Unfortunately the original engine was gone when I got it. I got it from a older friend of mine who`s brother in-law ordered it to pull a trailer. He doesnt remember what heads were on it but said it ran really strong. Cant remember why they yanked it but it failed somehow. Glovebox denoted the 454 with a TH400 and 3.40 gears. Only option was A/c that was missing everything but it was my first truck and it was free.

[natedogg]

I never understood why 305's get such a bad wrap. After all it is a small block and a lot better than a strait 6 or 4.3v6. Some of them actually had more hp than a 350. My 85 short bed has the numbers matching 305 still in it and runs strong and reliable. I drive it to work, not a drag strip.

[BaseModel]

Originally Posted by natedogg

I never understood why 305's get such a bad wrap. After all it is a small block and a lot better than a strait 6 or 4.3v6. Some of them actually had more hp than a 350. My 85 short bed has the numbers matching 305 still in it and runs strong and reliable. I drive it to work, not a drag strip.

Confession time: I'm more of a Ford guy, and my favorite engine of all time is the ford 300 inline six.

[68c10owner]

Originally Posted by natedogg

I never understood why 305's get such a bad wrap. After all it is a small block and a lot better than a strait 6 or 4.3v6. Some of them actually had more hp than a 350. My 85 short bed has the numbers matching 305 still in it and runs strong and reliable. I drive it to work, not a drag strip.

I think I have the original 305 in my 85 GMC and aside from smoke on start up its a strong runner. It`s my only vehicle and I drive it almost 50 miles a day round trip. Only thinking about the crate 350 because its cheaper than rebuilding my 305 and I cant afford the down time. This is my 3rd square with a 305 and they wont win any races in stock form but all have been every bit as reliable as the 350`s I`ve had.

[hatzie]

Nothing wrong with a 305. If it hasn't been abused or run to the end of it's service life it'll last just as long as a 350 of the same age and miles. The 400 smallblock is the engine with issues...

If she runs good and doesn't smoke run it. If you need or want more power get a 350 crate engine or a 454 or a 472 caddy or whatever other engine you want and decide to afford.

If she's smoking and feeling her age and you want an easy drop in replacement get a 350... Unless you have to get by the smog Nazis.