Is the 305 worth the effort?

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f6john

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I recently obtained an 85 Silverado C10 with 60,000 miles. The truck was driven less than 5000 miles in the last 10 years. The engine is 99% factory origional with the only visible change being capped vaccum lines off the thermostat housing. I have driven the truck about 1500 miles and it has a lot of issues. Starts good, but idles rough, worse at times but always rough. Power seems way off but my other truck is a Nissan Titan so I may be spoiled. The driveability issues are also annoying, sometimes while under light acceleration the truck seems to lose power and giving it more gas causes it to go slower until you let up on the throttle and go at it again. I have a 1995 Impala SS that I bought new so I am familiar with it and can tell when something is amiss and do most of my repairs myself. This year truck seems to be at a crossroads of technology for its day and I'm just not sure what all the issues were with engines of this time period.
I don't know the condition of the plugs, wires, dist. cap, or rotor but other than these "tune-up items" any suggestions on what to do to get this thing to run like a 60K motor should?
 

82chevy350

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id say since you just got it do a full tune up cap, rotor, plugs, Plug wires, check the timing, Rebuild the carb or Get a new one if that motor only has 60k i would defiantly say its worth the effort that stock 305 wont come close to that titan without alot of modifications
 

Old77

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My 77 had a 305 in it when I first got it and it couldn't get out of it's own way. I have no idea how many miles were on it but it was a complete dog and was more suited as a boat anchor than anything else. I threw it out, sold it for $50 and got a 350 crate motor from GM.
 

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My 305 was always a healthy motor. Healthy enough that it would actually piss me off when people would trash talk the motor and call it stupid things such as a "boat anchor".

Do the usual tune up stuff and see if that improves anything. The Titan I test drove seemed like it had less power than my 305, so I might be the spoiled one. If the tune up and carb/TB clean doesn't help, then I would consider swapping in a 350. These are good motors, but, not something I would really consider rebuilding.
 

Old77

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My 305 was always a healthy motor. Healthy enough that it would actually piss me off when people would trash talk the motor and call it stupid things such as a "boat anchor".

I was simply calling my particular 305 a "boat anchor". It was most likely due to age and generally being worn out. I have driven 305's since then that seemed to be very reliable motors and pretty healthy when maintained correctly. If I came off as calling ALL 305's a "boat anchor" I apologize.
 

Manbearpig

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lol my 355 is a boat anchor
 

Old77

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lol my 355 is a boat anchor

The 2.8 in my first s-10....now THAT was a boat anchor just on a little smaller scale. I could have physically run faster than that snail :D
 

Jaymez

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I was simply calling my particular 305 a "boat anchor". It was most likely due to age and generally being worn out. I have driven 305's since then that seemed to be very reliable motors and pretty healthy when maintained correctly. If I came off as calling ALL 305's a "boat anchor" I apologize.

I actually glazed over your reference and completely missed it. Nawh, I was talking about locals who would trash talk the truck because it wasn't a 350, yet, they had 4 cylinder S10's. That and those forum guys who always claim you can't get any power out of 305 yet chub up at the thought of finding a bone stock 85 Monte SS.
 

nxtlevl

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I actually glazed over your reference and completely missed it. Nawh, I was talking about locals who would trash talk the truck because it wasn't a 350, yet, they had 4 cylinder S10's. That and those forum guys who always claim you can't get any power out of 305 yet chub up at the thought of finding a bone stock 85 Monte SS.


Yeah, but those Monte motors were a HO305..........:roflbow:

Seriously tho, I've owned a couple of older vehicles with 305/307's in them, and one thing I noticed about the 305's was that they were infamous for flattening cams....That might have just been something that I ran into, but I had it happen to 2 '79 MonteCarlos..............

Now my ex father-in-law put a mildly built 305 into a '70-something Mazda truck he had, and that truck screamed...but there was next to nothing as far as vehicle weight....It was still a blast to drive.....:crazy:
 

Swims350

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I've seen my share of both, good and bad 305. I've also seen bad 350 and such. monte 3095 ho is BS, they aint no better then any other 305 IMO. The 305 that came out of dads 84 was decent in his truck, now it's in an 85 monte carlo and it's pretty mean. it'll turn tires over no problem and run really good on the highway. I think it's worth it if y6ou want something to beat around in and not a real "race" motor. If you're looking for alot of Hp or torque might want a 350 or big block. As far as something fun to play with or drive around 305 would be good.
 

Old77

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My future plans for the '77 is a big block but that's a ways off and will require substantial $$$ but it is definitely in the plans at some point

:driver:
 

nxtlevl

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My future plans for the '77 is a big block but that's a ways off and will require substantial $$$ but it is definitely in the plans at some point

:driver:

Well, get busy with that idea so we can figure out shipping price on your current small block.....:)
 

Old77

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Well, get busy with that idea so we can figure out shipping price on your current small block.....:)

:lol: If I remember right my current small block was around $4k to my door (including shipping and cost of the motor). I'm going to guess that's roughly $400 or $500 shipping.
 

85k10383

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To the OP, I don't see where in the country you are located but my suggestion in this:
If you can legally do it, strip the 305 of all of its EPA mandated equipment. Get the motor back to the basic piece of machinery that it is. You are 100% correct in your supposition that 85 was a "crossroads" year, it sadly was not a good crossroads. A great many of your driveabilty issues are probably hiding in the miles of vacuum lines and wiring controlling all of the spark and throttle control devices meant to give good fuel mileage and lower emissions.
 

f6john

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To the OP, I don't see where in the country you are located but my suggestion in this:
If you can legally do it, strip the 305 of all of its EPA mandated equipment. Get the motor back to the basic piece of machinery that it is. You are 100% correct in your supposition that 85 was a "crossroads" year, it sadly was not a good crossroads. A great many of your driveabilty issues are probably hiding in the miles of vacuum lines and wiring controlling all of the spark and throttle control devices meant to give good fuel mileage and lower emissions.


That's pretty much what I thought, but was looking for conformation. I am using the truck as an everyday driver and am looking for good driveability and reasonable performance for the engines size.
 

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