Rocket 350 vs. regular 350 - Whats the difference?

[brutus90]

I've asked a lot of people and haven't been able to get a straight answer on this one. What is the difference between a Olds 350 Rocket and a regular Olds 350. I have a 70 Cutlass S and, while it doesn't much matter now since the motor has been professionally built to the way I wanted it, I I'm still curious if it is a Rocket or not. I've heard that the more powerful ones are the rocket, while some people say they just call the olds 350's rockets. I'm assuming mine was the base 250 hp 350 since I had to change a few things to put it up to the 350 hp range. Could somebody tell me what the real difference is?

[MrPbody]

Brutus,

Most of the "Rocket" engines I've seen were 4-bbl. carbs. I believe the biggest difference between them are the air cleaner housing and valve covers.

In '52 or '53 (can't remember, but some Olds guru should), Olds introduced the Rocket V8. Virtually all OHV Olds V8s were called Rockets through '64 or 5.

You said it best when you described the changes needed. It really doesn't matter. It's an Olds... Unless it has a "W" in front of a number, it's no big deal. Even then, it's "debatable"...

Ever seen one that said "Ultra High Compression" on the air cleaner? Early '60s... Usually around 10.5:1...

Just ramblin' what I remember. Don't quote me...

Jim

[george85443]

ALL oldsmobile engines are rocket. Just like the logo.
ALL 307 to 455 super duper 442 or hurst are ROCKET ENGINES.
That's the name.

[DrRocket]

George is right. If it's an Olds, it's a Rocket.

Ride a Rocket!!

[hotrod_chevyz]

OLDS =*a left handed chevy* They have many differences, chevy being generally the better choice for performance builds.

Olds small blocks (260-403 cid) all have a 3.385 inch stroke. Olds achieves more displacement by applying different bore diameters .The 350 rocket has a 4.057 inch bore.

http://www.442.com/tech/enginearticle.html

Chevy 350 has a 3.48 inch stroke with a 4.000 inch bore.

http://www.mortec.com/

[brutus90]

Where does it say that the bigger bore 350's are rockets? If that is the case, then all Olds gas 350's produced between '68 and '80 are rockets, reguardless of the horsepower they produced. This, to me, doesn't sound right. I'm guessing Oldsmobile wasn't gonna call their low horsepower 2bbl 350 a rocket when they have the high horsepower 4bbl 350 sitting in the same chassis. I've just about given up on this deal anyway. I think the last guy that truly knew the difference is probably dead and gone.

[hotrod_chevyz]

Originally Posted by brutus90

Where does it say that the bigger bore 350's are rockets?

bigger bore 350? If its an olds 350 then its always the same bore and stroke. If the bore is larger than 4.057 inches, then its not a stock* olds 350. Some oldsmobile cars offered a 350 oldsmobile or buick 350 engine.

Originally Posted by brutus90

I'm guessing Oldsmobile wasn't gonna call their low horsepower 2bbl 350 a rocket when they have the high horsepower 4bbl 350 sitting in the same chassis.

Maybe the 2 barrel cars actually have a buick 350 and not an olds 350.

[brutus90]

Opps, I misread the 330 to be 350. My mistake. But back to the Rocket vs not a rocket. It didn't say anything in that article defining what a rocket is. It doesn't even go into anything more than some basic dimensions of the engine. It may be something such as a different combination of heads, intake, camshaft, etc., or there may be no difference at all. If someone reads this and knows for a fact it is one way or the other, please sign in and reply. I'm sure I'm not the only one that wants to know for sure.

I don't know for sure about any other years, but the vin number on the 70's I believe refer to only oldsmobile motors. The vin on my car indicates the low horsepower 2bbl 350. The car came with a 350 olds, but I'm not aware of whether it is original or not. If someone could verify the buick 350 coming within an olds body, also, please reply.

[hotrod_chevyz]

I know for a fact ive pulled oldsmobile motors out of buick bodies, i just figured if buick used olds, then olds might have used buick engines. Both companies shared a lot of platforms, but was more likely to do this in the 80's than in the 70's.

Everybody says its a rocket, if its a 350 olds block of certain year, than it is a rocket, no matter of what heads and other emissions stuff might be bolted to it. Its just a label for an olds motor, its not a mystery or legend. Maybe the weak ones were just too embarassing to put a rocket label on, but they offered a *real* rocket for those who cared.

[brutus90]

Ok, at the risk of sounding like an a$$, can you please tell me for sure if you know these two things: what exactly are the years of the Oldsmobile 350 rockets and what are the years when Oldsmobile put Buick 350's in their cars. People assuming, as you have done in your last post, are the reason why it's been so hard figuring this out. Just because GM did one thing doesn't mean they did it the other way around. Everyone either assumes this or that for whatever reason, and, yet, both can't be true. Some people say if it's an Olds, it's a rocket, while other people say only the higher horsepower ones are the rocket, and some may say that other things make it a rocket. It would be logical to assume some of those things, but, as we all know, GM wasn't exactly a model of consistancy. Again, if anyone knows for sure on the "Rocket" question, please post.

[84Buick]

350

Produced from 1968 through 1980, the Rocket 350 was entirely different from the famous Chevrolet 350. It used a 4.057 in (103 mm) bore and Oldsmobile small-block standard 3.385 in (86 mm) stroke for 350 in³ (5.7 L). 1968-1974 350s were painted gold, while 1975-1980 models were metallic blue, at which time the "Rocket" name disappeared from the air cleaner decal. Output ranged from 160 to 320 hp (119 to 238 kW). All Oldsmobile 350 engines had cast-iron crankshafts with harmonic balancers.
The Oldsmobile 350 was also produced with an electronic port fuel injection system, introduced in the Cadillac Seville of 1976.

[brutus90]

So, Oldsmobile = Rocket for sure. Thank you for the post and for looking up the info. I never did find anything other than the "I think" answer everywhere I looked. The info about the efi should come in handy, as I would like to convert mine to efi. I'll have to look into that though. Thanks!

[hotrod_chevyz]

Is it just me or did everybody (like 5 people) on this thread already say its a rocket>?

Guess the denial went to anger and then has gone to acceptance....

...next stage....depression.

[brutus90]

I guess I wasn't counting, but I definitly didn't count your replies, as I found some phrases as "I just figured...", "Everybody says..." and the worst one of all "Maybe..." to be less than acceptable to me. You may poke fun at me to your heart's content after you read this, but you can't blame someone for asking for proof when so many people think they know what's going on but have nothing to back it up other than "well, he said this".

btw...if I remember right, acceptance is the final stage. I guess that "might" not be the only thing you have backwards Look up Kübler-Ross model. Don't mind me...I'm just retaliating

[Mines69Olds]

I would be a good idea to look at the casting numbers on the engine block. If you could find a late 60's block it would be ideal b/c of the high nickel content that it has. It makes for a very nice and solid rebuild where you can get around 400hp and still be able to get 200,000 miles out of it. They are good, solid and tough as hell.