454 (block) with "HIGH PERFORMANCE" CAST INTO IT???

anybody ever hear of a chevy 454 with the term "high performance" cast into the rear of the block? a guy near me has one for sale. it's a complete, running engine. i ran the casting number on the block and it comes up as a chevy truck block. i don't know a lot about these, but i have never seen or heard of "high performance" being cast into the block before. is it a "high nickel" block?

thanks for your time and help,
steve

 

Common

 

Yup, real common truck block. Pulled many out in the mid to late 70's for spun bearings. They were in C20 and C30 pickups and sloburbans owned by the railroad. Light duty, 2 bolt main motors. Never did understand the hi perf casting!-MIKE

 

thanks for the replys.
i thought i might have finally found something worth a ****.
oh well. guess i'll keep diggin.
still a decent price though.
thanks again,
steve

 

I got one . I knew it didn't mean much but loved to show that to the knuckleheads that didn't know much about the motors...they were impressed.

Id like to know more about why its there though.

 

Some of the "hi-perf" blocks were drilled for external oil cooler bosses right above the oil filter, other blocks say "p***-perf". Sometimes 2 bolt and 4 bolt blocks may have the same #'s so you have to pull the pan and check.

 

Is there a foundy marking cast into it? Depending on where it was cast I might be able to find out more.

 

Just because it is common doesnt mean it isnt desireable.If the price is right you should buy just for resale if nothing else.They will do nothing but go up in price along with everything else.

 

I have seen blocks with "TRUCK" and "HI-PERF" both cast into them....doesn't mean much....the oil cooler bosses are more of a reliable indicator as to whether or not it has 4-bolt mains...although there are very valid reasons to start with a 2-bolt block & upgrade it to what you need, rather than start with a 4-bolt block.

 

Go here: http://www.mortec.com/bbc.htm
Those blocks are no big deal. If it's a truck block it might be what is known as a "tall deck" block.

 

Pretty sure it had to do with the deck height on these blocks. If its a truck block most aftermarket intakes won't fit because the heads will be pushed out from the crank centerline. Hi-Perf P*** blocks had the lower deck. Plus the truck block cam location was up higher, I think, so timing chains don't interchange. But then again I could be wrong.

 

I have a complet 72 402 big block with 400 long shaft turbo that i pulled from a 90000 mile car It is complet as pulled with ps pump I drove it on the trailer when I bought it. I live in delaware and would like to sell it. Bought it to put in a 57 chev but am nowgoing to use a sb with a 700r. E mail is dewvsc@verizon.net

 

Lots of them had HI PERF or HI PERF P*** cast into them in the bellhousing area some on the heads under the valve covers and on the block under the timing cover also if there is a 10 cast under the timing cover its a hi nickel block if it has 10 10 its high nickel and high tin block. I have even seen a block that said HI PERF *** no "P" I wonder if the foundry workers were messing around that day.

 

My 88 suburban has the same block in it straight from the factory.

 

I have blocks marked Hi Perf and Hi Perf P***. One is a 2 bolt 454 ( 010 ) casting out of a 3/4 ton, the other is a 68 435HP 4 bolt 427 block. My 67 350 hp 396 block has the Hi Perf cast on the heads and the block. My conclusion is that it means nothing.

The tall blocks will only be found in the big bolts.
The only major difference in the heavy truck block, was that the block is .4 inch taller than the car block. This is for the extra ring on the larger piston. All the cranks in the tall blocks are forged, but the balance is different because of the heaver pistons.
If you want to use a common aftermarket intake manifold on a tall block, you can buy spacers that fit between the manifold and the head. The big truck heads have what are commonly called peanut ports. That just means that the ports are smaller and will give you fantastic low rpm response, but run out of air at about 5000 rpm. They also have valve rotaters on them, but you can buy inexpensive adapters to eliminate them. The most common tall blocks are 366 and 427 ci.
There is a real good HP book on how to hot rod a big block that has all the good casting numbers. There is another good HP book on how to rebuild a big block that has a ton of good information.

 

It would have been somebody in the sand molding dept. most likely.

 

It was a great marketing gimic at first, but that ended up trapping many an unknowing person to buy used engines thinking they were "hi perf" 4 bolt main engines only to find out they were 2 bolts. Now, it means nothing as people have smartened up to it through the years.

 

that is so not true that this is a truck block run your numbers

 

Not if it's a 454. True "truck" blocks were 366 and 427.

 

If you run the numbers, that's an eleven (11) year old post from somebody who last logged on in December, 2017

 

Funny, here is it 2023 and I googled "HI PERF ***" and I see people talking about this old thread like it's dead. If you want it to die say it on Facebook. Forums stay alive forever. Now I know about my unique engine.

Thanks!

 

When I Google that I'm expecting something much different!

 

Another thread that won't die

Anyways, the HIGH PERF and P*** and TRUCK lettering seems to be related to which blocks were cast using which molds. The same end molds were used on all of them, so you see all three words on many blocks.

In other words, the words are mostly meaningless for figuring out what block you have. You have to go by other features, such as the deck height and oil p***ages, and of course the casting number, to figure it out.

 

Could be worse Jim, the "010" small block debate is a bit long in the tooth also.

 

It's the same old wives tales, with the same source...but since we don't understand how the casting process works, we can make up all kinds of neat stories about the markings.