427 vs. 454 ???

[wancosc356]

Ok. Well here is the idea. I am thinking of picking up a long block and building it. Nothing crazy. Just a solid, reliable motor with plenty of power.
My questions:
1.) 427 or 454?
2.) Any particular long block of either to be looking for?
3.) Will one be cheaper to build than the other?
4.) What can I expect to spend on one block versus the other?

PS> I found a 427 long block from a 67 chevelle. And a tall deck 427 from I dunno.

[JimKshortstep4x4]

The 454 with more cubic inches can make more power and will probably be easier to find. 427 tall decks are probably not suitable for what you are looking for as they can be expensive to build.

I would check the block numbers on the 67 "427" as I don't believe the 427 came in the Chevelles from the factory.

Jim

[watahyahknow]

from wat i remember of the books i read about the bb chevy some of the high perf 427's came with a steel crank as where the 454 are all cast .
427's seem to have thicker cylinderwalls as whell

[jim zag]

Just find a 454 out of a 70's Chevy truck and do a rebuild. If the crank is worn consider a 4.25 stroke crank from SCAT or Eagle and build a 489 STROKER. Keep the compression around 9:1 and a mild camshaft less than 220@.050 duration and you will have a T O R Q U E MONSTER sure to make you SMILE!!!!

[Hart_Rod]

454 will probably be the cheapest as they are the most plentiful. What tranny are you going to use? I've got a recently rebuilt turbo 400 (less than 200 miles) with mild shift kit, new torque converter, all the lines, deep sump tranny pan, flywheel and new transmission mount, $400.

[QKENUF4U]

do you want HP or TQ ? the 427 truck blocks are torque motors, the 427 car blocks are HP motors.... either way i would be happy unless i was drag racing.....
as for 427/454 isnt it the same block with different stroke (car block wise that is) ?

[PanelDeland]

When building an engine(from the same family)always go with the most CI you can unless there is a weakness you don't want to pay to overcome.More CI=morepower.And the cost is usually the same.I also agree with Jim,if you have to replace the crank"stroke it" since the cost is minimal and the power/torque gains are respectable.

[prostreetC-10]

You also have to remember that a 427 is a 454 block (4.250 bore) with a 396 crank (3.76 stroke). It will be almost impossible to find a true 427 block that is not a tall deck and you really don't want to me with one of those if you don't have too and if it's for everday driving. The key is your wording of getting a block and building it. Are you planning on paying for machine work? If you are wanting to buy one and just "freshen" it up, then you better either buy one that is running and in a vehicle or one that is completely torns apart. NEVER go off the claims of a seller. Every darn complete motor on a stand was recently "rebuilt" or "fresh". When testing a rig with a motor you plan on buying, never test drive it after they have warmed it up. In other words...you want to hear it start when it's ice cold. Since metal expands when it's warm, rod knocks and other things tend to go away or get quieter with temp. If the motor is on the stand, you need to pull both heads and look at the walls for ring scratching. They will be on the sides of the walls and not the ends from the piston being pushed and pulled by the crank. You also need to pull one or more (should pull all) of the mains and look at the bearings and crank. Do the same for a rod or two. A great deal means nothing if you have to replace a crank or maching the bores when you didn't budget too. If the person selling doesn't want you to do this....you should have suspicion. It's just too easy to do this and it will keep you from buying something that needs so much machine work that you would have been better off and money ahead to buy a basic crate motor. Good luck!!!!

[72blue]

427 has a better rod to stroke ratio. the 454 is trying to punch out the walls. but like everyone says, the 454 would be easier to find.

[QKENUF4U]

ya want a big block and not have to worry about BS then here ya go... get a nice book on building a BB and have fun.. personally this is what i would do if i was gonna build my ownn BB....plus ive used there engine kits and they have always been AWESOME KITS !!!!

http://www.pawengineparts.com/UnassembledBlkList.html

[QKENUF4U]

actually those are the short block kits. not sure why they dont show you the long block kits.... guess ya have to call but IMHO its the way i would go...

[capev86]

if i was running a big block i'd want fuel injection to make the most of it (and to save as much gas as possible). i am swapping out the original 307 for a 406sbc in my 72 suburban (2wd 3/4 ton w/ 3 on the tree) eventually. it will be running the 4 barrel quadrajet from my dad's 84 suburban but i will some day hopefully upgrade to mpi for better fuel economy and automatic adjustability for high altitudes on long trips towing trailers (i live at sea level). also swapping out the 4.56 rear gear for a 3.73 with limited slip as soon as i can. i like big small block for the weight savings and stealth look, but a big block is definitely a way to go for serious power and only a new duramax w/ a 6 speed allison would be cooler.

[wancosc356]

Originally Posted by Hart_Rod

454 will probably be the cheapest as they are the most plentiful. What tranny are you going to use? I've got a recently rebuilt turbo 400 (less than 200 miles) with mild shift kit, new torque converter, all the lines, deep sump tranny pan, flywheel and new transmission mount, $400.

I was thinking 700r4. But not sure yet. It won't be for a while though. This will be something done in time. Not right away. Thanks for the offer though.

Originally Posted by prostreetC-10

You also have to remember that a 427 is a 454 block (4.250 bore) with a 396 crank (3.76 stroke). It will be almost impossible to find a true 427 block that is not a tall deck and you really don't want to me with one of those if you don't have too and if it's for everday driving. The key is your wording of getting a block and building it. Are you planning on paying for machine work? If you are wanting to buy one and just "freshen" it up, then you better either buy one that is running and in a vehicle or one that is completely torns apart. NEVER go off the claims of a seller. Every darn complete motor on a stand was recently "rebuilt" or "fresh". When testing a rig with a motor you plan on buying, never test drive it after they have warmed it up. In other words...you want to hear it start when it's ice cold. Since metal expands when it's warm, rod knocks and other things tend to go away or get quieter with temp. If the motor is on the stand, you need to pull both heads and look at the walls for ring scratching. They will be on the sides of the walls and not the ends from the piston being pushed and pulled by the crank. You also need to pull one or more (should pull all) of the mains and look at the bearings and crank. Do the same for a rod or two. A great deal means nothing if you have to replace a crank or maching the bores when you didn't budget too. If the person selling doesn't want you to do this....you should have suspicion. It's just too easy to do this and it will keep you from buying something that needs so much machine work that you would have been better off and money ahead to buy a basic crate motor. Good luck!!!!

I do plan on actually building one. I would never buy a "complete running fresh rebuilt" motor unless I have proof. I would have a machine shop do the work that I cant. Thanks for the advice.

Originally Posted by QKENUF4U

ya want a big block and not have to worry about BS then here ya go... get a nice book on building a BB and have fun.. personally this is what i would do if i was gonna build my ownn BB....plus ive used there engine kits and they have always been AWESOME KITS !!!!

http://www.pawengineparts.com/UnassembledBlkList.html

Thanks for the suggestion. Ill check it out.







Thanks everyone else for the tips/tricks/advice/suggestions/info. I guess the verdict is in to go for a 454. Thanks again.