jb78L-82

It's a 4 bolt truck block..........

If you are looking to save money, go with a 383 using a 4 bolt 350 block....Can't beat it for power to size for the street. Use quality components (forged everything), roller cam, AFR type heads and it will make an easy streetable 500 Gross HP with more power than your C3 suspension and chassis can handle without modifications.

I would forget the BB in today's easy HP SBC world...really not needed or uesable on the street..great for bragging rights.

The LS can get expensive but great engines too. If money is no object go LS or SBC 427................

69ttop502

bashcraft

I ventilated a block in much the same way about 30 years ago. It was a '69 Mach I with a 390 and 4 speed but in the end, it looked very similar to yours. What caused mine to grenade was a valve broke and destroyed the piston (there is no piston on the rod that's visible in your picture). Without the piston, the rod just bangs around in there until it busts it's way through the block, thus the carnage. A piece of the block went through the oil filter and it pumped out a good bit before I got it shut down. I was only able to salvage one head and the intake manifold from mine.

BTW, I was racing a '70 challenger with a 383 at the time. He told the that the ball of fire was quite impressive.

bashcraft

Usually the ones who say don't go with a big block are the ones who have never had a big block.

sstonebreaker

Sorry for your loss. I hydrolocked my LS2 earlier this year and am going through the same process. One thing I found was that all forged pistons are not the same. There are two basic flavors: 2618 alloy and 4032 alloy.

2618 is the standard forged alloy everyone uses for big horsepower. It is very tough and is the most resistant to detonation. It has two drawbacks: It expands a lot when heated, meaning the piston to bore clearances have to be double what a cast piston is, which causes piston slap when the engine is cold; and second because the material is not as hard as hypereutectic cast pistons, it wears out much sooner. The wear is also accelerated by the pistons rocking in the bores from the large piston to bore clearances needed.

4032 alloy is what the OEM's use in their forced induction applications - LSA, LS9, LT4, and even the GM Performance Parts LSX 376 B15. Pistons forged from this alloy are basically halfway between hypereutectic cast and 2618 forged. They have the benefits of cast pistons - they are more thermally stable than 2618 pistons so the piston to bore clearance can be half what the 2618 P to B is, they are harder than 2618 so they wear much better; and while not as tough as 2618 pistons, they are much more resistant to detonation than hypereutectic cast.

Basically it comes down to this: If you're looking for upwards of 1200 horsepower, then 2618 is the way to go. Otherwise, the 4032 pistons are plenty tough and will be quieter and last longer than the 2618's.

The added advantage of the 4032 alloy is that because most folks want the toughest pistons, the 4032 pistons are slightly cheaper. JE's SRP Professional line and also most of Mahle's forged pistons are 4032.

jb78L-82

Correct...LS7 427 all aluminum small Block..in a C6 Z06

jb78L-82

Yup! See above^^^^^^^^^

bashcraft

Not sure what your point is, other than you've never had a big block and you're telling other people that they shouldn't use one.

jb78L-82

Not what I said..............Just curious, have you ever driven a car with a SBC 427 of any sort?

DUB

The 'point' is that a person can have 427 cubic inches of engine in a small block and NOT be a cast iron engine like back in the 60's-70's. 'Big block' cubic inches can be obtained by getting a LS7 which is all aluminum and can achieve stupid wicked power and actually have very decent mileage (m if desired) due to it being computer controlled.

I have had a cast iron big block but I also have also worked on the LS7's and they ARE very impressive and I know I would not go with cast iron big block even if it had aluminum heads due to I can get the same if not more out of the LS7 just by mapping things out differently and making some changes and it is all wrapped up in a lighter small block. Cost of horsepower/torque ratio increase to dollars kind of thing may or may not be thrown out the window. Keeping in mind if the car does not need to meet emissions...things can change DRASTICALLY. for the better.

Now I guess this now possibly started a battle on how much money someone spent to achieve 'X' amount of HP and torque and the weight ratio to that HP/torque. Which is or may be impressive to some people...but for me...I do not care. It seems to never end. The battle of bragging rights. So when a person gets to work on and be around 500 cubic inch nitro funny car engines with 8000+ estimated HP...anything less... is kind of a joke. Being able to see and realize what an engine can actually do when it is not on fire or blowing up.

DUB

jb78L-82

Thanks Dub for helping to explain for some^^^^^^^^^. THIS IS EXACTLY the POINT!

You can pretty much make the same or more useable HP from a SBC today....and if cost is a consideration why not do a SBC that is smaller and lighter (even a cast iron 383!) versus a cast iron BB? If you are interested in handling even one bit, BB's are NOT the way to go...well known and documented......

40 years ago you needed the BB cubes to make the power..no longer true!

pauldana

I suggest a large tube of JB Weld... that should fix her right up...

DUB

I kind of have to agree to a point...even though I know I would not attempt it. With the current adhesives that are being made..they can do some really impressive things and actually when used in some areas are stronger than a weld. Not an opinion.. but rather a FACT.

DUB

TimAT

OMF

I kinda wish I had two cars.....the one I have now with a small block, and a stripped down one with a full cage and a big block.....barely streetable of course.

OldCarBum

I only have one to build and I chose a barely streetable big block.

NewbVetteGuy

CNC Motorsports build some GREAT short blocks.

If you think you might ever want to upgrade to a forced induction combo a DART SHP Block is good for 700HP and they'll support huge bore sizes.
Dart SHP 406 4.155" bore; Scat forged crank, Scat H beam rods, balanced, & blue printed, SHP Forged pistons (11.4:1 CR): $3,989.95

It's one hell of a strong short block for the money. (They have a version with 9.0:1 CR which can still make a really nice NA combo today and would be a great basis for a turbo addition later....)

-If my current block ever dies a catastrophic death, I'm getting one of these...

Adam

bashcraft

It is what you said, and I still don't know what your point is.

lionelhutz

That's not a small block....

So, I'm not really understanding your point either.

DUB

OBVIOUSLY a LS engine is not JUST LIKE cast iron small block. So seeing how there are some who are beign critical here...it is pointless to try to lead the blind and I will leave it as those of you who just not understand the point due to they are obviously wanting a keyboard battle and more than likely did not read everything to possibly help them see the light. If this applies to you...then it is what it is.

BUT for those who may want to know....and possibly try to see it...what many of you may not be aware of. When considering the displacement size of the LS 1 engine when they first came out with them they were 5.7 liters....which ...oh my gosh....is the same displacement of a 350 cubic inch SMALL BLOCK from years prior..

And FUNNY how the same engine block casting size of that LS1 engine can have 427 cubic inches be made to work from it.....hence....LS7 427 SMALL BLOCK....as some people call it. BECAUSE...obviously GM did not need to cast a much larger engine block to accommodate for the 427 cubic inches like they did back when they came out..

DUB