[Pats70ss]

I apologize as i feel sure this has been discussed before, but if one wanted to build a 496, which model 454 block should I be on the lookout 4, I assume would want to try and find a 4 bolt main? or are you better off buying an aftermarket block?

Thanks

 

[69_CHEV_ELLE]

I'd be looking for 70 LS6 if I had a 70SS car.

 

[71350SS]

Block casting numbers of 3999289.... 361959 .... 3963512..... 14015445 .
These are the most common blocks I know of that I've seen that were 4 bolt main 454 motors. Keep in mind that a good portion of these engines were also 2 bolt mains and the only way to be sure is to look under the oil pan.
I have a 3999289 454 with this casting number however it is a 2 bolt main. If you can find a good 454 grab it, 4 bolt or 2 bolt main they're all strong enough for a 496.If you're building an all out drag motor by all means look into an aftermarket block.
One good thing about the late model 454's is I think all the Gen V and Gen VI 454's are 4 bolt mains.

 

[123pugsy]

The late models are also set up for roller cams and have a one piece rear seal.

 

[66rat]

Depending on HP goals a 2 bolt main block will more than handle the horsepower for a typical street car.

 

[blm]

I have a 289 block and it’s a 2 bolt. I ask my engine builder and he said no worries about using a 2 bolt. Now it’s a 496.

 

[Pats70ss]

It will be a street car..hoping for high 500s in the HP range. Will just dona nice set if aluminum heads, a stroker kit and good cam..nothing crazy. The motor build will be quote a ways down the road but figure if I stumble across a block I could snatch it up.

Assuming $500 range for a block?

 

[blm]

That’s what I paid about 4 years ago. The block I bought (Craigslist) the seller had receipt for having the bare block cleaned and crack checked at a engine/machine shop. That is also my hp and torque range. Sure allows the Chevelle to giddy up.

 

[mrpaticular]

Gen 6 is a roller block. Some have fuel pump boss. Cannot remember which one does not accept the manual trans pivot ball.
I'd say closer to 500 hp. Close to 12.50 , 1/4. But if you go slow and seek info here you can be faster. Just remember faster means a lot more $$$$.
Tons of factory blocks running in the 10' s. Many in the 9 's.

 

[bracketchev1221]

HI Pat, any block will suit your needs for that power, I've made 700 on a 2 bolt block with main studs in it. The biggest issues are making sure the block is square. meaning you don't want one with excessive core shift because it throws off alignment and can cause thin spots. If possible I would look for a standard bore block if you can find one. My preference would be a standard bore and build a 489, yes it doesn't have the ooh and ahh of saying 496 but it helps keep the cylinders more stable.

 

[Pats70ss]

HI Pat, any block will suit your needs for that power, I've made 700 on a 2 bolt block with main studs in it. The biggest issues are making sure the block is square. meaning you don't want one with excessive core shift because it throws off alignment and can cause thin spots. If possible I would look for a standard bore block if you can find one. My preference would be a standard bore and build a 489, yes it doesn't have the ooh and ahh of saying 496 but it helps keep the cylinders more stable.

Is the 489 a stroker kit as well..just assume standard bore is the difference?
Appreciate all the feedback..like I say project is a ways off but I would grab a block whenever I see a nice deal on one that way I have it when needed.

 

[mr 4 speed]

2 bolt block is fine for a 496, even it makes 700 HP

 

[65cayne]

Is the 489 a stroker kit as well..just assume standard bore is the difference?
Appreciate all the feedback..like I say project is a ways off but I would grab a block whenever I see a nice deal on one that way I have it when needed.

Yes
.030 over bore vs .060

 

[mrpaticular]

489 will allow an extra bore job to 496 without going through the expense of buying and tooling a different block. I would go 489.
Properly prepared 2 bolt block will go 700 hp @ 7000 with ARP bolts.

 

[Malibu ss 64]

Personally I would go with a mark IV block. 2 bolt with std bolts will be fine for what you want. ARP studs or bolts need at least the mains to be checked and maybe linehoning.
Ive only owned one 4 bolt 454 block.
500 hp is doable very easy with 4” stroke so if you find a good 454. I would be tempted to use crank and maybe even rods from it.

 

[John Milner]

I have several 1990 model 10068286 casting 4 bolt main 454 blocks. I think all with the 286 casting number are 4 bolt main and are a Mark 4 block with a 2 piece rear main. However a 2 bolt engine will be just fine and plenty tough.

 

[shovelrick]

Watch Vortecpro engine builds on Youtube, he shows what to look for in 454 blocks for a solid build, I picked up a 1975 "959" 4 bolt block that had been bored .030 over, ARP main & head studs for $450 about 3 yrs ago from a mechanic friend, check with local engine rebuild shops for a 454 block that someone never picked up

 

[123pugsy]

HI Pat, any block will suit your needs for that power, I've made 700 on a 2 bolt block with main studs in it. The biggest issues are making sure the block is square. meaning you don't want one with excessive core shift because it throws off alignment and can cause thin spots. If possible I would look for a standard bore block if you can find one. My preference would be a standard bore and build a 489, yes it doesn't have the ooh and ahh of saying 496 but it helps keep the cylinders more stable.

Awesome.

I love saying 496....it does have that great sound rolling off tongue.
The few more HP for 7 cubes doesn't roll off the tongue so well though.

 

[mrpaticular]

Others are right. Look for a 454 short block. Use everything but the main and rod bolts and pistons. Build a 4", 461 or 467. Most good builds will out run a typical 4.25 stroke. Street cruising you will never know the difference.

 

[Pats70ss]

I am on the hunt for one