Big Block Chevy's

[DuckusCrapus]

I just drug home my first Big Block. It was just the short block, but it was cheap enough. Not sure of the year, but it is a 454 , 4 bolt main and I am thinging it was late '80's-early '90's. The crank has some nasty scuffs on the journals and might not be able to be turned. We'll see. That is actually one of my questions.

• Should I forget turning the 454 crank and go with a 496 setup? What all is needed to do such a swap?
• What are "good " casting numbers for heads?
• Can somone prove to me that rectangular ports are better than oval?

I am going to take this thing to the machine shop to have it checked out and freshened up, but I would like to know a game plan before I do.



Thanks
DuckusCrapus

[EdwardTeach]

First off there truly is no substitute for displacement...send me the numbers and I'll tell you exactly what you have cause I got the books...that info is easily found online too...just do a search for mark IV chevy engine numbers...I have a few different motor manuals (old vintage stuff) I would gladly loan you for awhile...rectangular ports are the way to go because of the flow...they can be found after some searching...my dad bought a 65 head which had to have come from a Z16 velle or a big hp vette because of the casting number and the other head was a 66 casting corvette both heads in great condition with only mod being stainless seats but otherwise bare very good condition castings from a drag boat guy by Sandsprings for 400 bucks a couple of years ago...bargain post find..so they are out there at a reasonable price...find the drag boat guys and you'll find alot of old school chevy BB stuff...nowadays they are doing different things so they are letting go of those parts...Johnny Bigblock and those hotrod guys tend to keep their stuff...after my dad gets his vette put together this summer I'll see if he has any leftover stuff...I know he has extra headers and radiators and oval heads and a vast assortment of extra stuff...

[EdwardTeach]

BTW that crank needs to be perfect because you are talking a lot more torque and ponies...the son of buck would be a great thing for the lead sled bondo pig...get some 500 hp action and put her on the spray and hold on tight...major frigging @ss puckerer know what I mean??? hahhahahhaha

[Maro]

Duck, I got a BBC guru.....I'll talk to him tomorrow during the drunken guitar fest.....hopefully he answers before we drink all the wine.....

[64ChevSS]

Here is an article on rectangular vs oval ports.
For oval ports 781 and 049 are the best factory casting.

[Okiecockfighter]

I thought everyone new about moretech ???? Im sure the crank will turn and for what your doing the 454 setup should be fine unless you wanna break stuff . . . then you can build the big motor !!! Im building a 496 motor right now using the scat rotating assembly for a boat. . . Boats dont have the same issues a car has on breaking parts due to torque so thats why i opted for the kit when i found out the crank was junk. I gotta set of aluminum rect. port heads that are gm winners circle 67-69 427. . . Will need once overed at the machine shop but everything looks okay !!! Will trade

[DuckusCrapus]

Thanks for the replies. I was not too sure what to do with this thing when I got it, but if the crank is turnable I will most likley stick with the 454 not the 496. The stroker kits are quite a bit cheaper these days, but still around the $1300 range and that is with cast stuff. Sounds like sticking in the 454 land with some good pistons and a little squeeze would really rock pretty well.

But I am getting ahead of myself. I don't even have a car I want to put this thing in yet. Unless my SBC is a bust in the '55 I can't see putting it in there.


Anyways. Here is the casting number on the block if you wanted it Teach.

14015445




DuckusCrapus

[DuckusCrapus]

Here is an article on rectangular vs oval ports.
For oval ports 781 and 049 are the best factory casting.

You have the link you were talking about?



DuckusCrapus

[64ChevSS]

Here is the link Duck!

http://www.maliburacing.com/ovalvsrect.htm

[EdwardTeach]

number indicates 78-90 2 or 4 bolt...
What is interesting reference doesn't say Mark IV engine (14015443 says Mark IV, truck, RV so maybe 445 is passenger car specific???)...makes me wonder if there are two types of fat blocks for the era...hummmm
Did Chevy put 454's in any cars during the 80's??? I can't think of any...

[DuckusCrapus]

Well the block has HIGH PER PASS cast into it where the timing chain goes. And is deffinitley a 4 bolt block.


When I picked it up I wouldn't have known the difference whether it was a tall block or not. But after looking at it and seeing the "Pass" cast into it, I think I got a good deal.

I am heading to Carter's Machine shop here this next week and will most likley have Burt look at it. He might be able to fix me up with some heads later down the line.



DuckusCrapus

[mac762]

Hey Duck here is some recomended reading for a new BB owner. I got mine after I put the motor together. It would have been a lot better if I read em first. Big Block Chevy Performance, and How To Build Max Performance Chevy Rat Motors. The first book is probably the better of the two but they both have a lot of good info in em.
One thing that blew my mind about BB's is you have to use a domed piston for any kind of comp, that part is a lot different than small blocks. So I had to find some closed chamber heads with 98cc chambers just to get my flattop motor up to a 9.3 to 1 comp.

[DuckusCrapus]

I got a generic book on just stock rebuilds. I wasn't sure on how dated some of those performance books might be.

I am going to take all the stock stuff to the machine shop to see if it can still be used. If the block is still standard, then I might try. I also wanted to know what kind of pistons they are. I have no idea n how to tell cast from forged.

I have a NOS kit that I need to buy som new solenoids. Would be cool to have a 454, a good dingle plane intake, big carb and 200 hp of spray.



DuckusCrapus

[Dirtylarry]

454s

number indicates 78-90 2 or 4 bolt...
What is interesting reference doesn't say Mark IV engine (14015443 says Mark IV, truck, RV so maybe 445 is passenger car specific???)...makes me wonder if there are two types of fat blocks for the era...hummmm
Did Chevy put 454's in any cars during the 80's??? I can't think of any...

Trucks and more trucks actually the closed chamber 65 model heads are a good compromise for Duck the 65 has 1.88 exh valves hard as hell to find
If he wants to run pump gas. 9 to one is fine with the so called gas we can get. The 55 is a perfect canidate. The juice will work better wo so much squeeze. Use forged flat tops IMO
Most rats say hi perf pass behind flywheel. The interesting part to me is the 4 bolt mains.

[mac762]

Yeah Duck, Those books I mentioned are old, but have a lot of good info. If you really want the scoop on BB Chevies hang out over at "Team Chevelle", I bet about half of the guys there have BBC.
I was gonna tell you that when I bought my shortblock it was gonna cost $400 more for 4 bolt mains. I got the 2 bolt. They say 2 bolt BB's are good for over 600hp. Later Josh