1971 Oldsmobile Rocket (?) Engine Rebuild

[fleming442]

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!!

Nice to see you here, Mark! Some serious Olds advice is needed 'round here.

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 . . .

It's wrong because building an engine with a goal of a certain power level is a complete package. Olds are not Chevies, and you need someone that knows them. You'll come up short ordering random parts off the internet if you don't know how it will come together in the end.
I highly doubt an aluminum headed big block is lighter than a small with iron heads.
Personally, unless you're on a budget or restoring it to concourse factory, I see no reason to not get aluminium heads. Irons are limited on lift, need hardened seats, weigh more, and have the exhaust crossover ports.

 

[olds307 and 403]

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 . . .

What you are saying is true, for near stock manners. Your big cubes allow mild manners with 450 HP. Even with the 4" stroke and 4.125" bore for what 428ci, it is still over square and has light parts, unlike your 455. I bought used custom pistons for a 4.390" bore with a 330 crank offset ground for a 3.5" stroke, meaning 424ci with my 403 block. I would not have spent one penny on less cubes for a flimsy block. I may get it together before I die but need to spend about a grand in parts for my 2004R to live and another grand for the 3.90 posi first. The 350 is just a better starting point than the 403 due to block strength.

 

[Canon_Mutant]

Well, the sad thing is, we aren't even arguing here. Every single proposal to make 425 horsepower involves "cubic inches". Not a 350.

And, since I've actually done it, a 455 block with Edelbrock heads, Performer Intake, and a FlowKooler aluminum H2O pump just for the flow rate [might save a lb or 2], weighs 40 lbs less than the small block did. Though I am still running the factory air, I did remove the air pump since I didn't need it [7-8 lbs maybe?], the factory air cleaner for a drop 14" since it wouldn't fit under the hood [maybe what 3 lbs?], and not sure what going from the one heavy cat into the factory 2 1/4 inch exhaust compared to true dual 2 1/2" through high perf Magnaflow cats into 22" Magnaflows does to the weight? And, I added a 4 row cooler up front which was likely a pound or two more over the 3. Everything else [then] was the same.

Doing some weight reduction and front to rear bias stuff with my current project but no idea where that is leading yet?
So far, it's a large expensive paper weight.

Progress is actually happening this week though . . . if you can believe that? I promise . . .

 

[MrSony]

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.

Whats the name of your outfit, do you have a site?

 

[Cutlassefi]

My business name is Remmel Auto & Marine.
I'll have a Facebook page shortly but I've been in business for over 10 years. This is a sideline business for me but it's been very rewarding helping the Olds community.
One correction on something someone said.
Iron heads aren't necessarily lift limited. If the guides are cut correctly they can handle lifts well into the .600's.
I hope I can help here, I've seen some incorrect info already. I strive to be part of the solution, not part of the problem.
Thanks!!