Yes, I have bought a few parts off them. They just came out with a heavy duty aftermarket BBO block that can make big power and cubic inches. Plus another company has billet head cores that can flow big air.
1971 Oldsmobile Rocket (?) Engine Rebuild
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I always like to ask what you intend to do with this when you are done? If this is a street cruiser, the amount of work required to get those power numbers out of a small block can be done but this motor will NOT have pleasant road manners. Now, if you are going live on the drag strip, then that is a different story.
Small blocks have to spin to make the kind of numbers you are seeking. This requires carburetor, intake, heads, and exhaust that will flow the air, and a really large cam and high lift capable valve train to feed it and then you need to spend money on the lower end to make it live at higher rpm ~ 7000 or so. If any piece of the airflow puzzle is off, your power production goes accordingly. When you are all done you may get there but the thing will have horrible street manners because you won't be getting into your power until about 3500rpm.
A mild big block gets you there yet maintains the pleasant street manners because it is there from 1500-5500. And, with an aluminum top end, you can build one that is actually a few pounds lighter than your small block. Just throwing that out there for consideration. Mine is a 442 so I wanted to get historical 442 type power numbers while maintaining streetability and even fuel efficiency. After spending literally years looking at all the options for the very limited 307, considering 350, 403, punching and stroking out a diesel block which I originally got my 425 crank to do, almost going with the [then] new Aurora-Caddy motor heavily modified, and even considered LS conversion for at least 10 minutes, I went big block Olds and have never regretted it.
Good information here: http://www.442.com/oldsfaq/ofe350.htm#E350 350CIDEngineDetail
Sounds like an interesting project once you sort out the details but be realistic with what your goals for the car are going to be? I would MUCH rather have an efficient 300HP 350 on the street that is snappy quick with the right gears behind it even though there is always someone quicker than an over the top build that may get you to 425HP that has to idle at 1200-1500rpm and is generally pretty doggy and horribly wasteful literally dumping gas out the tail pipes until it comes to life just before the red lights are in your rear view mirror.
Good luck with it . . .
Small blocks have to spin to make the kind of numbers you are seeking. This requires carburetor, intake, heads, and exhaust that will flow the air, and a really large cam and high lift capable valve train to feed it and then you need to spend money on the lower end to make it live at higher rpm ~ 7000 or so. If any piece of the airflow puzzle is off, your power production goes accordingly. When you are all done you may get there but the thing will have horrible street manners because you won't be getting into your power until about 3500rpm.
A mild big block gets you there yet maintains the pleasant street manners because it is there from 1500-5500. And, with an aluminum top end, you can build one that is actually a few pounds lighter than your small block. Just throwing that out there for consideration. Mine is a 442 so I wanted to get historical 442 type power numbers while maintaining streetability and even fuel efficiency. After spending literally years looking at all the options for the very limited 307, considering 350, 403, punching and stroking out a diesel block which I originally got my 425 crank to do, almost going with the [then] new Aurora-Caddy motor heavily modified, and even considered LS conversion for at least 10 minutes, I went big block Olds and have never regretted it.
Good information here: http://www.442.com/oldsfaq/ofe350.htm#E350 350CIDEngineDetail
Sounds like an interesting project once you sort out the details but be realistic with what your goals for the car are going to be? I would MUCH rather have an efficient 300HP 350 on the street that is snappy quick with the right gears behind it even though there is always someone quicker than an over the top build that may get you to 425HP that has to idle at 1200-1500rpm and is generally pretty doggy and horribly wasteful literally dumping gas out the tail pipes until it comes to life just before the red lights are in your rear view mirror.
Good luck with it . . .
When you have picked out a machinist that you trust, and knows their stuff...making a streetable 425Hp is not difficult, and very reliable. I have a '78 403 with 455 "J" heads, a Performer RPM intake, Crane 1.7 aluminum rockers/pushrods/guides, with a lopey idle that's rock steady 750 rpm. This motor pushed an '85 442 to a 11.8 quarter mile. It's totally reliable...tap the key to start... and has no problems starting in the cold Canadian climate. Oldsmobile V8s sound different then any other American muscle...even the exhaust has a different smell...It smells like...VICTORY! 😉
Hello,
I am new here. I will post my info in the new user section but happened to come across this thread.
I offer Olds engine building and dyno services. I'm in Central Florida so I'm not that far from you I believe.
I agree with most of what's been written to this point with a few exceptions.
When using Edelbrock heads you would still use a small block intake, not a big block one. Also without good heads your target of 425hp will be difficult to achieve so put your time and money into the heads. And your '71 doesn't necessarily put out 310hp in stock trim so you'll need to spend a few bucks to get to your goal, sorry.
In addition I hope to be offering a stroker crank kit for all Small Block Olds from '64-'90. Let me know if I can be of any help. I'm an Olds owner as well and try to contribute to the Olds community whenever possible.
Thanks!!
I am new here. I will post my info in the new user section but happened to come across this thread.
I offer Olds engine building and dyno services. I'm in Central Florida so I'm not that far from you I believe.
I agree with most of what's been written to this point with a few exceptions.
When using Edelbrock heads you would still use a small block intake, not a big block one. Also without good heads your target of 425hp will be difficult to achieve so put your time and money into the heads. And your '71 doesn't necessarily put out 310hp in stock trim so you'll need to spend a few bucks to get to your goal, sorry.
In addition I hope to be offering a stroker crank kit for all Small Block Olds from '64-'90. Let me know if I can be of any help. I'm an Olds owner as well and try to contribute to the Olds community whenever possible.
Thanks!!
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Glad to see you joined Mark. Your stroker kit is a nice option for more power easier. I believe the 71 was actually 260 HP gross, 200 net. There are less issues in building the 350 for power vs the 455. The heavy rotating assembly and big bearings need everything done just right to not self destruct. The Olds 350 is very under rated, was the most reliable 350 in my books.
+1 on this. The only practical stroker option I had back when I went big block was a diesel block punched and stroked which I really wanted to do but was going to be quite a bit more money than I put in my big block. I heard about the 330 cranked options but didn't personally know anyone that could do it? And, though they often had reliability problems with the windowed block and heating problems with the huge bore, the 403 was/is indeed a capable HP engine but we are talking 53 more cubes in stock form than a 350. I still think 425HP out of a 350 will end up WAY too wild for street use. Would LOVE to see an Olds 383 type build . . .
Well my cranks should be done in the next couple of weeks. The first batch are 5140 forged 4.00" stroke, second batch will be 5140 forged 3.875" for a 414ci build with a 4.125 bore. Rods and pistons will be off the shelf items. Throw a set of bb heads on it and you'll be in the 450hp neighborhood WITHOUT a lot of camshaft.
I'll be doing a couple of builds to show what can be done. Just want to bring some options to the Olds community.
Again, great news! Wish you had you been around 11 years ago as I really wanted to stay small block but new I would need to stroke a 350 to get where I am at with a mellow big block.
But, with these stroker kits, we are now talking about big block cubes here, folks, not a 350. Can someone tell me what I said below that is not true or to be disliked "about a 350"? I mean, if I'm lying to folks, I need to know it . . .
But, with these stroker kits, we are now talking about big block cubes here, folks, not a 350. Can someone tell me what I said below that is not true or to be disliked "about a 350"? I mean, if I'm lying to folks, I need to know it . . .
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