305 Motor Pros and Cons?

[86swb]

Aireman1952, What did the 302 come in? (Ford?) I never had anything with a 302 in it. By the way, you forgot the 350. I see this is your first post. Welcome from Kentucky.

[Boog]

Well the 305 is a mid engine between the 6 cyl and a 350. Back when it first came out it made pretty good fuel mileage in cars like the Nova and Chevelle. I think it was intended to passify the buyers who wouldn't have a six but needed the fuel mileage. Certainly not a powerhouse by any stretch but still a good small V8. However if and when my 305 goes south I will also be replacing it with a 350!

[Longhorn Man]

86SWB the 302 everyone thinks of is the 5.0 in the fords.
However Chevy had one one year before ford did. Ford's came out in 68... chevy had theres in the 67 Z-28. The 302 was built to fit in the 5 liter class in the SCCA trans am class. A high revvin solid lifter small block that would rev to like 7 grand or something crazy like that.
All 67 - 69 Z-28 cars had this engine. And it is worth quite a bit of cash to have the 302.... with or with out the camaro

[Green Machine]

Does it make much sense to build a 305 for big HP ? well no. Does it make much sense to build a 454 for gas mileage ? well no. My next motor is going to be built for gas mileage and it will likely be a 305. Not pulling anything, no 4wd, so a well thought out 305 should have more power tnat the worn out stock 283 it will replace. Check the cam specs, all non HO 305's from early ninetys back to 1976 all had smaller cams the the 350's that certainly didn't help any. Back when, 283's 327's and 350's used the same base cam. Even a bone stock 350 cam will wake up most any 305 - my 2 cents.

[davidh]

Has anyone read the latest classic trucks where they took a used stocker 307, threw on some edelbrock alum vortec heads,intake, carb, like a 262 comp cam, may been the 4x4 series. anyway they brought it up 85HP!!! They were suggesting using these motors behind your low dollar projects since these 305, 307, 283's are usually cheap. A second thought is you could rebuild a 350, keep the stock heads and be cheaper than the article's 307. I plan on doing something different for my 67 longbead. I don't plan on pulling alot with it but it will run errands and be a great scout vehicle. You know pull up in the old truck when you go to offer cash for vehicles instead of pulling up in a 50K duramax diesel 4x4. they know you have deep pockets!

[llegos]

i want a 302 chevy, but it wouldnt be very practical in a truck...

[Old Yeller 1970]

For dependability and longevity a 305 will last just as long as a 350. Performance wise you can make a 305 with Vortec heads run like a 350 with older style heads in stock form.

If you don't need the power and you're not going to do heavy towing a 305 with stock heads is a great engine. If you can get a 305 with Vortec heads you'll be pleased with the power it provides and it's ability to do some towing.

I have a beater automatic '86 GMC with no telling how many miles on the 305 and it still gets 15-17MPG.

[airman1952]

Hello 86SWB. Thanks for the welcome. Yes, I realized I forgot the 350 right after I hit the reply button.

I had (Now, I wish I still had) a 69 Z28 with the 302. That car flat out screamed in factory specs. I had a set of Hooker headers on it, with
the old Cherry Bomb glass packs. (I'm dating myself) For back then, that thing really sounded good up in the powerband RPM's.

[Dick Dale]

For low buck, I would take a 283 over a 305 or 307.

[RPOZ11]

Originally Posted by airman1952

Hello 86SWB. Thanks for the welcome. Yes, I realized I forgot the 350 right after I hit the reply button.

I had (Now, I wish I still had) a 69 Z28 with the 302. That car flat out screamed in factory specs. I had a set of Hooker headers on it, with
the old Cherry Bomb glass packs. (I'm dating myself) For back then, that thing really sounded good up in the powerband RPM's.

*********************************************************
I've had several 69 Z's and one was an Azure Turquoise X-RAM car. I used the factory 585 Holleys and a 140 cam and MAN! The car ripped! Thru all 4-gears after 3000 that thing flat out was evil!
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ON the 305:
I have one in my 84 GMC with a 700R4 behind it! (ECM! :-( )
I recently drove to Phoenix from LA and back and I will tell you that every uphill grade I lost 15MPH in 4'th(OD). I had to leave it in 3'rd on every hill! The fun part was the downhills and got her up to 90+ MPH.
I have had the heads re-done leaving the 1.84 intake valves but added hard seats, gasket match ported the I/E ports, installed a 262 cam, port matched the Intake manifold and I still have this result.
I like my 305; it is great on flat around town and highway driving.
My thoughts are if I were to keep and reuse the 305, I would consider a stroker crank and longer rods for better weight pull-even loaded(mine was basically empty on my drive). I like the 305's more water around the cylinders for better cooling in hot weather or under demand driving as mine never peaks over 185*!

[skillet]

Originally Posted by Dick Dale

For low buck, I would take a 283 over a 305 or 307.

You got that right! My first truck was a '67 stepside SWB with a 283. It was my step-dad's truck and he rebuilt it 2 yrs. before he gave it to me. I drove it for 17 YEARS without ever touching the motor. For me it was the perfect blend of power, economy and simplicity.

[corn]

I had an 82 that had a 305 in it. I put a 350 cam in it when the stock cam lost a lobe & it woke it up BIG TIME. Was no drag racing machine by any means but it would spin the wheels pretty good...corn

[airman1952]

**********************************************************
I've had several 69 Z's and one was an Azure Turquoise X-RAM car. I used the factory 585 Holleys and a 140 cam and MAN! The car ripped! Thru all 4-gears after 3000 that thing flat out was evil!
**********************************************************

My 69 Z was, what think I remember they called the color, candy apple red. When I used to "drag the gut" in the small town in Montana, that I grew up in, my Z would sound like a piece of crap idling around with my cheezy exhaust system. However, just on the edge of town where we would normally turn around and go back through, there was a mile or so straight stretch. Everyone would like to kick it in the a$$ on that stretch. That 302 would lite up at about 3 grand, and I could actually get that thing to wind up near the 8 grand mark. (prob. not healthy for it) In that 5000 RPM span, that d#$% thing would run, and sound just like a nascar. (scary!) I turned more heads with that car than you could ever imagine! Oh, the memories!!!

[Tx Firefighter]

The beauty of a 307 is it's crankshaft. The 307 crank drops into a 350 block with no mods. That makes the 327. Use normal off the shelf 327 pistons.

[blood62]

i realy dont like the 305 especaly the older non vortec ones had 1 die on me 2 seize and one leak more oil than i could dump in though they were all beat before i got em... i would go with the 327 or 350

[nowicu812]

Been thinking of building a small one too. Might type 305 Hamb in the google search and check it out. Mighty mouse. If I new it was for real for sure id build one. $2.45 for 87 today this afternoon.

[kq4pc]

Hello all, been reading all the input of motors.tought i would put my 2 cents in.i have ran a number of 305,s over the years.not a hot rod motor,but have had nothing but good service out of them.i have a 302,with angle plug heads in a 56 belair,beleve me it is more than enough power.i have been offered crate motors for mine.i have seen the 302 go for 6500.00 on e-bay. thanks Bobby