GM 305 cleaning out... How should I proceed

Originally Posted by bullwinkle
Originally Posted by Chris142
Originally Posted by BAJA_05
Cheap conventional oil like Super Tech 5W30 paired with a Super Tech filter and run it 1000 miles;)
x2. Warren makes great oils.

The 305 was known for it's v8 fuel economy with v6 performance!

That's when they weren't eating cams, losing valve seals, and basically being the gutless turd of the SBC family!

You have never driven a 262 then
lol.gif
makes the 305 seem fast.
 
Originally Posted by bullwinkle
Originally Posted by Chris142
Originally Posted by BAJA_05
Cheap conventional oil like Super Tech 5W30 paired with a Super Tech filter and run it 1000 miles;)
x2. Warren makes great oils.

The 305 was known for it's v8 fuel economy with v6 performance!

That's when they weren't eating cams, losing valve seals, and basically being the gutless turd of the SBC family!


The cam issue was 78-83, after that they didn't seem to have any issues other than valve seals and valve cover gaskets which got better in the late 80s and up. Plus those were not a 305 specific issue, it was any small block Chevy. The 350s from 75-86 had crack prone heads which the 305 did not, so the 305 was probably the most reliable SBC over the years.
 
Originally Posted by caprice_2nv
Originally Posted by buddylpal
I've had plenty of 305 chevy's in the past. They aren't picky at all. I always ran 5w-30 which was specified in the owners manual but plenty of people use 10w-30. I always used synthetic M1 back then. I'm sure today's conventional oils will be more than adequate at cleaning out your engine.

I have a soft spot for 305 chevy's, the Chevy Caprice with the F41 suspension and performance axle definitely changed the whole feel of the car. The 305 wasn't well loved by the enthusiast community but I will say there is a stark difference between the carburetor vs fuel injected versions. The fuellys had decent performance, although someone looking to add more power was better off with a 350. The tuned port injection engines offered decent power but the TPI was finicky at times and long term not reliable. The throttle body versions were dead reliable and they still function to this day. The TBI engines didn't make as much power as the TPI but they still had more power than the carburetor ones. The later version 305 became part of the vortec family and they are pretty reliable too except for intake gasket failures and also fuel injection issues.


I don't agree with the TBI having more power than the lg4 305s, at least compared to higher compression 9.5:1 85-88 version. My 86 that got wrote off and my 86 parts car with only 110k miles will roast the tires off. My 83 with 8.5:1 Cr is a lot slower but still faster than my TBI 89 (I also had a second one for parts with only 230k miles and it drove the same as the 335k mile one). The swirl port heads on the l03 engine were pretty lame, nothing like the tuned port injection or vortec 305s. The TBI was probably the most reliable other than having to do an intake manifold gasket once in its lifetime. They are aluminum intake, the older carbed ones like my 83 are cast iron and never seem to leak.

The worst thing about the 305 is valve seals and valve cover gaskets will leak, and even if you fix it, they will leak again within 10 years. My Olds 350 hasn't had any leakage problems.


Doesn't bother me that your agree or disagree, toot your own horn. I just did a quick google search and it appears the LG4 305 has less horsepower than the TBI versions.
 
Originally Posted by buddylpal
Originally Posted by caprice_2nv
Originally Posted by buddylpal
I've had plenty of 305 chevy's in the past. They aren't picky at all. I always ran 5w-30 which was specified in the owners manual but plenty of people use 10w-30. I always used synthetic M1 back then. I'm sure today's conventional oils will be more than adequate at cleaning out your engine.

I have a soft spot for 305 chevy's, the Chevy Caprice with the F41 suspension and performance axle definitely changed the whole feel of the car. The 305 wasn't well loved by the enthusiast community but I will say there is a stark difference between the carburetor vs fuel injected versions. The fuellys had decent performance, although someone looking to add more power was better off with a 350. The tuned port injection engines offered decent power but the TPI was finicky at times and long term not reliable. The throttle body versions were dead reliable and they still function to this day. The TBI engines didn't make as much power as the TPI but they still had more power than the carburetor ones. The later version 305 became part of the vortec family and they are pretty reliable too except for intake gasket failures and also fuel injection issues.


I don't agree with the TBI having more power than the lg4 305s, at least compared to higher compression 9.5:1 85-88 version. My 86 that got wrote off and my 86 parts car with only 110k miles will roast the tires off. My 83 with 8.5:1 Cr is a lot slower but still faster than my TBI 89 (I also had a second one for parts with only 230k miles and it drove the same as the 335k mile one). The swirl port heads on the l03 engine were pretty lame, nothing like the tuned port injection or vortec 305s. The TBI was probably the most reliable other than having to do an intake manifold gasket once in its lifetime. They are aluminum intake, the older carbed ones like my 83 are cast iron and never seem to leak.

The worst thing about the 305 is valve seals and valve cover gaskets will leak, and even if you fix it, they will leak again within 10 years. My Olds 350 hasn't had any leakage problems.


Doesn't bother me that your agree or disagree, toot your own horn. I just did a quick google search and it appears the LG4 305 has less horsepower than the TBI versions.


I'm aware of the HP specs, 165hp for the later year lg4 and 170 for the L03. That's not what it feels like to drive them though. I agree with everything else you said but driving several of each I guarantee the lg4 works better than the TBI.
 
Originally Posted by Chris142

You have never driven a 262 then
lol.gif
makes the 305 seem fast.


Or a 267. I acquired a 267 in a package deal in the early '90s. I put it in car I was selling that needed an engine. No matter that it had dual exhaust, a bigger carb and a 350 camshaft, it was just a slug that only got about 18 mpg.
 
Originally Posted by Chris142
Originally Posted by buddylpal
I've had plenty of 305 chevy's in the past. They aren't picky at all. I always ran 5w-30 which was specified in the owners manual but plenty of people use 10w-30. I always used synthetic M1 back then. I'm sure today's conventional oils will be more than adequate at cleaning out your engine.

I have a soft spot for 305 chevy's, the Chevy Caprice with the F41 suspension and performance axle definitely changed the whole feel of the car. The 305 wasn't well loved by the enthusiast community but I will say there is a stark difference between the carburetor vs fuel injected versions. The fuellys had decent performance, although someone looking to add more power was better off with a 350. The tuned port injection engines offered decent power but the TPI was finicky at times and long term not reliable. The throttle body versions were dead reliable and they still function to this day. The TBI engines didn't make as much power as the TPI but they still had more power than the carburetor ones. The later version 305 became part of the vortec family and they are pretty reliable too except for intake gasket failures and also fuel injection issues.


The early(mid to late 70's) had very soft blocks. The bores wore out quickly and caused oil burning. That is what started the dislike for them. A couple years ago I drove a 66 chevelle with a 305 and an edelbrock top end plus cam. Car had 3.31 gears and was very snappy and fun to drive. A 327 would have been even better.


Why would someone drop a 305 in a 66' Chevelle?
Guess they had a car with no engine and a spare 305. A few weeks back we had a 32 Ford in the shop with a Chevy 262 in it.
 
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