350 small block vs 427 big block?

So, I've picked out my project car-a 1969 2-door Chevy Impala. It doesn't come with an engine in it, but it originally had a 427 in it. When I finish this car in a couple years it'll be my primary car and I'll give my Xterra to my son (if he ever nuts up and gets his license). The question I'm facing at this stage of the planning process is whether to go with a 350 small block or a 427 big block when I get the engine. On the one hand, the car originally had a 427 in it and would fit perfectly, but on the other the 350 will be a smaller cost up front and I could always go to a big block later. There are so many arguments for both engines, but as a newbie I'd really like some opinions on which would be the better way to go at the start. Thanks!

I’m glad you posted this as I would like to hear what people think of both engines. I have a Cheetah replica frame and will need a motor for it. I am on the fence between small block and big block, 327 vs 427. 

Looking forward to what others have have to say.

Though I'm an old skool SBC honk, it appears the path forward would be an LS swap that using the right 'pieces' would equal if not surpass a BB427 in all aspects. Not to mention less weight up front.....don't know your budget etc., but good luck!!!  Is this Impala two door post or the fastback?

In reply to 759NRNG :

No clue ¯\_(ツ)_/¯

Cheapest is the 350 SBC, millions around, huge aftermarket support. Unless you have a good sized budget and fuel economy is not an issue the 427 BBC would work. LS properly done would give you the big block performance and decent fuel economy for a car that size.

Build a 454 big block for it, will look the same as a 427, but cheaper and more common.

LS engine is another option, they can cost a bit more due to swap stuff needed. Fuel injection is a bonus.

350s are everywhere, but for some reason they seem to be climbing in price. Couple years ago my old man bought a new* long block from summit (260hp variant) for around $1400. Same engine now is closer to $2k. But used ones are everywhere and cheap, and rebuilds don't get cheaper than the SBC. The price of BBC stuff has me questioning why they are still used. Modern LS stuff is getting nearly as cheap as the old small blocks, and they can run with carbs if that is your thing, though you will need a computer to run ignition. Still, not uncommon to find a running 4.8 or 5.3 with harness and computer for around $1000.

TOO MANY ACRONYMS!! Please define:

• SBC
• BBC
• LS

Thank you!

(Please keep in mind I'm one breath up from a total noob, and am more apt to call things 'thingamajiggers' and doohickies' than to know the actual names.)

The body style pictured above is the 1969 Impala Sport Coupe. Also available on the Impalas that year was a Custom Coupe - which was the more formal roofed two door that had been on the Caprice body style for a number of years. The fastback body style that 759NRNG referred to were from the 1967 and 1968 model years.  

In reply to deannathegeek :

SBC - small block Chevy V8

BBC - big block Chevy V8

LS - The Chevy V8 series of motors produced starting in 1995. Standard duty blocks were cast iron,while performance editions are all aluminum with cast iron cylinder liners.  

In reply to agp1956 :

Thank you! 

For a big 'ole Impala like that I'd go BBC. If it was really originally a 427 I'd go that way. It'll be worth more and nowadays where values on anything from the 60's have gone crazy it makes sense.

having owned and semi-daily-ed all your options... i strongly recommend LS. its too much trouble and reliability drops to run and older SBC with mods needed to make equivalent power. BBC, just add fuel, lots of fuel. tons of fuel. not going to be a great daily. LS motors can be pulled complete from a variety of vehicles. if it were me i would buy a complete truck or van that came with a iron block and use the entire drivetrain. you will end up much more reliability, fuel economy and make as much power as you can afford.

It also depends on what your eventual plans/dreams are for the car.  You've picked a car that appeals to you, so what is it about the car that made you choose it?  That should help guide you on where you would like to go.  Couple of examples:

1. If you bought it because you just wanted something older and simple to learn on, then I'd go for the 350 and call it done.  You could learn rebuilding a motor on the most plentiful engine made, learn bodywork, maybe welding rust, interior sewing, painting, etc.  If it's more of a learning vehicle, go for the cheaper route to enjoy.
2. If it was a "mom/dad/favorite uncle had one and it brings back memories" then I'd still stay with the 350, as it's more of a nostalga purchase and not to be period correct, but concentrate on the bits that remind you.  Maybe the color or the wheels or the sound of the exhaust.  Whatever would make you smile when you recall the original.
3. If you really like that bodystyle and feel there's some collector value in it (I know nothing about classic American car collect ability) or you want it to be, then you should work on getting everything else perfect (like bodywork, trim, etc) while you save up and do some hunting for a 427.  It'd still be a learning opportunity, it'll just cost more.  You'd be hitting less junkyards and more swap meets to figure out all the original bits for the car.
4. If you want a classic car with a more modern feel (usually referred to restomod), then a modern LS engine would be a good bet.  If you go full restomod, you could put in an LS (get ready, they were plentiful and come in anything with a V8 from GM from 1995 on), upgrade the suspension, upgrade the brakes, more modern interior, etc.  Depending on how much you scrounge (like pulling a 4.8L LS motor from a wrecked truck, figuring out what suspension pieces from later GM cars are bolt on) it could be only slightly more expensive than option one.  You could also make it really expensive by buying off the shelf (and might for some things).  Plus, you'd be looking modern car stuff (electronics, fuel injection) while also learning the basics.

Hopefully, that helps and doesn't made it even harder to decide....

-Rob

In reply to rob_lewis :

You totally helped dude. 'Restomod' isn't a word I've heard before, but it totally fits; I love classic cars and I want mine to feel classic but with some modern touches. The plan is to get the car and totally gut it before going to town on the body work. The floorboards in the back seat are rusted through so I'll be re-learning the welding skills I learned in high school. I also plan on converting the front bench seat to bucket seats and doing the upholstery myself. Basically, I'm sure it'll take me at least a year to do all the body work I want to do to make it sexy AF (working on it between 2 jobs, school, and kids), giving me time to save up for a 350 or 427, whichever I have the money for when the body is done. While I'd prefer the 427 because I love big blocks, I'm ok with a 350 because it will be my primary car and I should pay attention to how much gas I'll be using, so long as it's still loud & powerful. 

Glad I could help.  If you're going that route, a 350 would be fun to learn and build, but with similar effort, I'd go for an LS motor.  Cheaper buy in (probably) pulling a good one from a junkyard, but about the same for the brackets, accessories and fabbing up the wiring.  Old carburetted motors are fun, but if it'll be your daily driver, I'd highly recommend you move to fuel injection for reliability.  You can still put headers and a nice exhaust (and they're powerful), but with with a much more reliable motor.

Good luck!

-Rob

In reply to rob_lewis :

That was actually gonna be my next question - carburetor or fuel injection. Thanks!

OK, another big question-how the heck would I convert back to a small block from a big block? There's gonna be hella room in the engine bay-is it gonna look all wonky? What am I gonna need to do to downsize?

In reply to deannathegeek :

Should only need the mounts (engine and trans). Cars of that vintage had space under the hood no matter which engine came in there. Like, room to hide bodies. 

After you have installed the engine, accessories, battery, and anything else you want, if you still feel like there is too much empty space just put a nice big pair of turbos. Rear tires aren't supposed to have any tread anyway.

427!!

If you want power, reliable and modern starting/driveability, the LS series of motor is the only way to go. Modern fuel injection and ignition is so much better than a carb and points or HEI. Lots of choices and you can get  modern auto transmission as well so it will get much better mileage when you don't have your foot into it than you could ever get with a 350 or 427/454 big block. If it were me,  I would choose the more modern engine. RestoRods are the latest craze and they have a lot of advantages in many ways. 

barefootskater said:

In reply to deannathegeek :

Should only need the mounts (engine and trans). Cars of that vintage had space under the hood no matter which engine came in there. Like, room to hide bodies. 

After you have installed the engine, accessories, battery, and anything else you want, if you still feel like there is too much empty space just put a nice big pair of turbos. Rear tires aren't supposed to have any tread anyway.

Turbos made of bodies?

barefootskater said:

In reply to deannathegeek :

Should only need the mounts (engine and trans). Cars of that vintage had space under the hood no matter which engine came in there. Like, room to hide bodies. 

In most Chevy platforms, SBC and BBC engine and frame mounts are interchangeable.  You could build a basic 350 to run around in, and slowly gather the parts for a 427 if you wanted.

If your goal is to make a bunch of power, an LS will be a cheaper place to start.  If you just want something to cruise in, and it doesn’t need to be a drag strip beast, a SBC is the probably the cheaper option.  I’m not sure what power level the LS takes to be worth it, but it’ll depend on how much scrounging you feel like doing, and how quickly you can jump on deals when they come up.

agp1956 said:

In reply to deannathegeek :

SBC - small block Chevy V8

BBC - big block Chevy V8

LS - The Chevy V8 series of motors produced starting in 1995. Standard duty blocks were cast iron,while performance editions are all aluminum with cast iron cylinder liners.  

From what I understand the LS is not necessarily a Chevy engine, it is a GM engine.  Mostly just semantics, anyway the LS is primarily found in Chevy products but can also be found in Cadillacs. I don't know why I felt the need to point that out.

If I was looking at building that car as a daily driver, I would strongly consider the LS engine over the small block or big block. It's currently without an engine anyway. It's easier to get a very good used LS V8 and they come in many performance flavors. You could start with a stock 4.8 or 5.3 to make it a more affordable roller, then find another LS to rebuild into a monster.

I'd lean towards dependable and easy to live with but with a nice sound and stance if I planned to drive it every day.