305 Motor Pros and Cons?

[skillet]

Is the 305 a good motor? Like say in a '93 Chevy truck? All I've dealt with is 283 and 350. Thanks for any comments.

[krue]

It's a dog, imo.

[N2TRUX]

There is nothing really "wrong" with a 305. It's just like the old saying that " their is no replacement for displacement" meaning why not go with a 350.

[Fatback]

It all depends on what you want to use it for. I owned a 1979 Chevy Truck w/305, for 11 years. I never had any problems at all.....though not a hot rod. The later 305's got a little more power.
I am running a 1996 305 in my 70,I am very happy with it. I dont plan on racing or pulling a travel trailer.It is a good motor for a daily driver, But if you want high performance, it's not the best choice.

[phantom dually]

I have a 305 in my 94 c2500. Great motot until you pull something. Pulls fine just not fast ebough for me!! My 94 just turned 68K original miles.

[bad68bowtie]

I've got a 305 in my truck and it doesn't make much horsepower and doesn't make up for that in gas mileage either. I would definitely go for a 350 or even somethin like a 327. I guess the 305 gets the job done but it is a dog and I can only imagine what it'd be like if I didn't have headers on it with an Edelbrock carb. and intake.

[86swb]

The 350 is a better engine in my openion. The 45 extra cubic inches makes a difference. That 350 is just a all around great little engine. IMO

[Woody]

In most cases the 350 will get the same or better gas milage as the 305. I put a '85 305 in my '69 years ago. It was a good motor just didn't have a power. The first 1/2 throttle was peppy, but from there to the floor there was no response. You couldn't even tell when the 4 bbl came in. I called it my nutless engine, because it had no balls.

I got ~13 mpg with it. The 350 that it replaced got 12.5mpg with a good tuneup and had the power to move the truck.

[Tx Firefighter]

They usually do suck powerwise in "stock tune".

I've run a few of them that I rebuilt with flat top pistons and a better cam and they wake up decently.

Remember, on most of them, the factory compression was low enough to start with a pull rope and the cam lobes a practically round.

[Jason915]

The earlier ones were DOG's due to low compression and the emissions requirements. They can be made into great running engines though in fact the L-69 ran better than allot of stock late 70's early 80's emissions 350's. My uncle has a 68 C20 with a stock L-69 305 out of an SS Monte and it runs much better than my grandma's 79 C-20 with a 350. You can build a 305 that will have plenty of power for a daily driver and will do better on gas than a 350 if built right. I wouldn’t go out of my way for a 305 but if I had one available to build I wouldn’t hesitate to drop it in a light duty truck or Blazer. The L29 Vortec 305 runs real good and it gets good MPG. A friend of mine just built a 305 for his 86 Blazer and it runs strong and gets 18 MPG on the Highway and this is what it is

305 .030 over w/ flat top pistons
L29 Vortec cylinder heads
Comp Cam CS X4 250H-11
Edelbrock intake
500 CFM Q-Jet
Full Length headers
HEI has been professionally tuned and re curved


With 3.42 gears this Blazer actually moves quite well and tows a 16’ fishing boat with no problems.

[A.P.]

I throw my 305 away and installed a 350. Much better engine.

A.P.

[Tx Firefighter]

Originally Posted by A.P.

I throw my 305 away and installed a 350. Much better engine.

A.P.

I like guys like you. That's how I've gotten several free 305's.

[garold99]

I had a 305 in my 79 Camaro. It was a piece of crap. I think the joggers could outrun me. Swore I would never own one again. Running a 350 now and love it. I do like the 327's also.

[roger0080]

Fatback sums it up best.

I swapped the 307 out after it died to a used 305 and I liked it. I used it for a daily driver. All depends what you want.

[A.P.]

Tx Firefighter if I would of known you wanted another 305 that was no use to me. I've would of send it to you. I tried to give it away to my family or friends near by my house, but no body wanted it after I told them it was a 305. So I was forced to throw it away in the auto junk yard.

[73737373]

Everyone has different tastes and opinions, some purely speculative, others can be backed by fact. We ARE and interesting group.

[Longhorn Man]

Tx noted the one good thing about 305 motors... they can be had in any part of the country for free, or not much more. IMO, anyone who pays more than 100 bucks for a non rebuilt 305 long block is getting ripped off. (Talkin older carbed ones here, not the Injected ones)

[stepside454]

from a purely performance standpoint dollar for dollar a 350 is a much better choice obviosly....unless you get a good runnin 305 for free. as far as are they a good motor, sure, they are as reliable as most any other small block.
As someone stated earlier, properly preparred , they can run very strong. I had a 305 I built in my 86 GMC Caballero that ran 13.70s with 3.08 gear, idled nice, 16" of vacuum & great MPG. so I think callin a 305 worthless is a bit dramatic.

[ChevLoRay]

Man, I remember when the hottest small-block was a 283, "bored 60". Seems like that was what we called a 301. Then, Chevy came out with the 327, for '62. You could swap the crank into a 283 block and then you had a 301.

The 307 was a smog dog, that may have been issued with good intentions, but never had anything going for it. I scammed onto a 307, and a 60K mile 327 (275 Horse), plus 4 pairs of heads, from my late uncle....all back in '79. I had a '67 Impala that had a worn-out 283 that I intended to replace with the 327, but sold the car and finally gave away all the other stuff. Oh, well.....

I think the 305 is a more usable engine than the old 307, but like has already been said....there's no replacement for displacement. I'd like to have a good 406 to put in my truck, but there's also a 427CID small block out in the market place.......but, no money in the budget at this time for that new engine. When I do, I am thinking that the 383HT crate engine will do the job for me....with a 700R4 behind it.

[Long Roof]

My Bro-in-law had a Monte SS with the 305 and it wasn't horrible. I think he got it into the 14.50's. Hell my stock 96 Impala SS barely got into the 15.80's, and before you start screaming about weight they were only 700#'s apart.

305 is an o.k. engine if that's what you have to work with. I wouldn't thow it away.

Aaron

[stepside454]

from a performance stand point I think the ol smogger 307 can be built with possibly better results than the 305 due to the 307s larger bore & short stroke allowing quicker revs & less valve shrouding. either way both can offer decent street performance...neither would be well suited for heavy hauling or towing of course.

[HeavyD]

Just for curiosity, if a 305 and 307 were built with decent cam, intake, good carb, and a little head work, which would get better overall mpg?

[stepside454]

assuming you mean under normal driving conditions....not loaded down, Id have to say the 307. under load the 305 might do better than the 307

[matthufham]

my mom's 95 1500 with a 305 is pretty darn nice. it's a strong motor, but the 4l60E behind it is terrible. we were sitting at 110,000 miles when we towed for the 1st time. we changed the fluid after we got my truck home, and it's been slipping ever since.

[airman1952]

Hi. First post! Have a 72 k20 with the 402.

Just my opinion, a 305 is just another GM small block. It all depends on how
much goodies you want to put on it to make it run! It's biggest problem is
that "305 cubic inches" just does not sound very sexy! 283 - 302 - 327 - 396- 427 - 454 !!! Now, those sound good!

I have an 84 Z28, with the L69. For an 80's generation car, it does not run half bad!