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Rocket 350 vs. regular 350 - Whats the difference?

02-21-2006, 04:14 PM
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?

02-22-2006, 01:45 PM

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...


07-23-2006, 09:57 PM
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.:sunglasse

08-17-2006, 01:48 PM
George is right. If it's an Olds, it's a Rocket.

Ride a Rocket!!

08-18-2006, 02:01 AM
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.

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

08-22-2006, 10:06 PM
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. :disappoin

08-23-2006, 12:48 AM
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.

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.

08-23-2006, 07:35 PM
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.

08-24-2006, 02:36 AM
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.

08-25-2006, 06:18 AM
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.

08-29-2006, 04:42 PM

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 (

08-29-2006, 06:28 PM
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!

08-31-2006, 03:26 PM
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.... stage....depression.:smokin:

09-01-2006, 12:19 PM
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 :grinyes:

09-06-2006, 11:31 AM
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.

09-10-2006, 05:34 AM
Im sorry if my replies were below your standards. Ive worked on more oldsmobiles than i have probably anything else. Perhaps you should join a oldsmobile club, you could probably find one that knows quite a bit about cutlasses ect. They will probably expect a fee but for the exact information you seem to desire it might be your best bet. You get what you pay for.

BTW No reason why you should feel a *retaliation* is in order...I was sort of joking around, i didnt expect that you would take offence to anything i said. I believe you took the situation as being more intense than it actually is. Is it too bold of me to say "lighten up">?

Chevys gets a minimum of one cutlass a week in for work. Ive worked on more cutlasses in the past five years than i really care to even think about. Still to this day i have people who owe me cash money for transmission rebuilds and engine rebuilds on oldsmobiles and cutlasses. The owners of these cars seem to have some chip on their shoulder for some reason or another... Ive done so many engine pulls and plantings on those i can do them in the dark. Seems like they always have the same problems, such as coolant in the oil... So good luck with that. If your engine puts out as much power as you claim it might be a fairly nice ride.

Also, welcome to the forum, sorry again if you took what i said as some type of offence, i was just trying to help. I found a book up at the shop with some info you might find interesting, but now instead of posting it i think im just going to leave this thread as it is.

As for looking anything up, i really dont think thats going to happen in this case. I did browse for a few minutes through a dusty old book trying to shed some light on this particular topic, but after your last reply instead of trying to live up to your standards, i think i might leave the light off on this one. Once again good luck.

09-11-2006, 10:59 AM
I think it would be hard to work on Cutlasses all the time b/c I have only seen a few running around here. I mean in 5 years i've not seen more than 10 late 60's early 70's running around. I've had coolant problems with my cutlass before but it was my 85 Cutlass supreme with a 3.8. Some info just kinda seems like it doesn't all add up.

09-11-2006, 11:42 AM
I guess I do have high standards when it comes to accurate information. Sort of a "This is how it is, and this is why it is that way". I'm going to leave that response as it is, since it seems to be common sense and needs no further explanation.

As for the retaliation remark: you probably know as well as anyone that written things can be interpereted very differently. That is the way I took it. If that isn't the way you ment it, I suggest you reread some of the things you may post, as people (including myself) may misunderstand your humor.

In regards to you doing work and not getting paid for it: I think common sense should be looked upon in that one as well. None of my business as to why you don't get paid for your work though. I personally wouldn't stereotype the oldsmobile crowd though. It doesn't matter if you're a chevy, ford, oldsmobile, or whatever kind of guy. There are guys (and girls of course) that have a chip on their shoulder, regardless of which brand they like. Mines69Olds was talking about cooling. Thankfully I've gotten 15,000 on mine with no problems to speak of, including cooling problems. Oh, and I don't claim that my Olds has that much power, the professional engine builder that put mine together claims that.

Also, whether or not you actually looked up information on this subject or not, it doesn't really matter as you apparently aren't going to share (I'm reading that as "I know something, but....too bad, I'm not gonna tell you"). Oh, and the part I mentioned about looking up was regarding something totally different, but oh well. Hopefully someone got it.

Finally, thank you for wishing me luck, although I question how sincere it is.

Mines69Olds - The guy that put my Olds 350 together also said that about the high nickel content. The guy is an Oldsmobile building freak, and I got a lot of info that I never even knew I wanted to know (too bad I lost his phone number). He basically told me to keep the RPMs below 5500 to be safe (I guess going a lot higher than this might scatter some metal), change the oil religiously, and basically keep it in tune, and that motor will pretty much out live me. He knew I wanted a nice street car to pound on occasionally, and he pretty much said "here ya go, just take care of it".

Gotta keep the Olds' going. I see chevelles all over town, but not many cutlasses. Speaking of which, mine needs a drive :naughty:

09-12-2006, 03:45 AM
The north side of OKC has a lot of Cutlasses. mostly post 75. Most of the ones i work on are 80's models with 70's model engines.

Sometimes people cant really afford to pay or they would. When it comes to some poor family if they are a good loyal customer, even if they dont pay me right then they will always be back and probably with the cash they owe me.

I wasnt stereotyping at all. The Cutlasses i work on are owned by gang members who have nice custom paintjobs, and 22 inch wheels on rubber bands. They drive impalas and other big bodied old schools, not only Cutlasses. Payment isnt the problem with these boys. Its more like, while im doing an oil change on one gang car, another gang car pulls up for a wheel swap, and they are a rival of one of my other customers. Pretty tense but i get a lot of work from them.

09-12-2006, 06:53 AM
I'm done posting replies to you, hotrod-chevyz. That's great that you can help people out in a bind as I do the same, but the previous post made it sound as if these oldsmobile guys you deal with had issues. But, as I said before, it's none of my business. Anyway, this thread has become counterproductive, and unless there is a post actually pertaining to the thread topic from you, I don't intend on replying.

05-20-2008, 04:58 PM
Olds 350 is any engine produced by Oldsmobile from 1968 to 1980 with bore of 4.057, stroke of 3.385 and output of 160-320 hp. Rocket 350 is any Olds 350 engine bearing the "Rocket" name until it was dropped from air cleaner decal in '75. Earlier Olds 350s (all Rocket 350s, '75 & '76) are desirable since blocks are "durable and full of power potential." What is the difference between Olds 350 & Rocket 350? The model years that did not bear the Rocket name. Whoo, ahhh!!! Big fraggin' deal. Oldsmobile had been using that name since the 50's. That's really it. You guys can debate how many horses it takes to qualify as a Rocket 350 all you want. Be my guest. When you come to a consensus, let me know. What do you mean by regular Olds 350 or regular 350??????????????????

05-20-2008, 06:43 PM
Welcome to AF, please look at the dates on the threads ,this is way too old.

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