Brinell hardness of a factory block?
 

Does anybody know what the brinell hardness of a stock pontiac block would be? I have a chance to buy a blemished IA2 block but it is a little soft at 180 brinell. Do you think it will hold 800-850 HP reliably on the street? Thanks

Steve

You might want to read this paper on Brinell hardness for OEM Blocks.

http://www.afsinc.org/files/images/iron%20alloys.pdf

From what I read 180 barely meets the bottom spec for a cast iron OEM block as far as material strength.

But you still would have a block with 4 bolt mains, (steel caps and splayed outer bolts), thicker cylinder walls, more material in the valley, stronger lifter bore design, etc.

Some years ago a Pontiac family bought some blocks that were not quite up to spec and eventually both blocks had issues, Failed.

That being said, Marty Palbykin (with a 1967 factory block) with splayed caps installed and some block chryo treatment ran a 1600 hp Twin Turbo engine for 3 years before a crack developed. Is the engine NA and what rpm are you assuming?

Tom V.

Tom, D1SC procharger street driven, not raced. I am stepping up from stock iron heads to ported edelbrock and do not want to ruin the current 455 assembly. I will turn about 5500 rpms. I was assured this block could hold 800HP but I also don't want it to be an expensive lesson.

Interesting link Tom, thanks for sharing.

Years ago the infamous MR-1 "butter blocks" were a minimum 145 and maximum 150



.

Brinell testing is mearly a snap shot. It doesn't take into consideration heat cycles and prolonged load cycles. I've ground on blocks that on the surface seem hard, but once material is removed, you find casting porosity that weakens the block.

Btw, I've not seen any casting or porosity issues with a factory block.

Calvin Hill
Hill Performance
708-250-7420

Calvin,

I'm trying to decide if I should chance my current 455 with a street 800 HP or would this "softer" IA2 be a better option. I might just buy a regular IA2 and just skip this "softer" block. I drive this car out on trips and play with it a lot, the last thing I need to do is break the block when I'm 8 hours from home.

Steve

If there is any one within driving distance( 6 hours) that does cryogenic treating I would take the IA block there , get it treated and then run it!

All IAII blocks are 220 ish bernell. We had a foundry use stock cast iron on 4 blocks. 2 are left for sale as a blems. They are not sold as a high end blocks. They are marked blem. But good for a stock to mild engine build. With all the engineering and machine work of a STD race block but normal engine casting marterial. You can't prep a stock block this nice, this cheap. They look great and would be a help to someone who is looking to save a few bucks.

I do not think that Marty's block would have held together that long had the stroke been longer!

Bob,
I guess the ultimate question is will it hold 800 HP reliably. I don't consider 800 HP a mild build. If it will hold it reliably I will send money now!!!!


Steve

Yes/no... At the rpm he was running(7800 iirc) you are probably right. I think differently if a 455 was the base, a much lower rpm could make and sustain the same power level for same amount of use...different turbo's required to do that.

Buy a good block it is the foundation.
Because if 800hp is good 1000hp is better.

Good luck

I'm trying to decide if I should chance my current 455 with a street 800 HP or would this "softer" IA2 be a better option. I might just buy a regular IA2 and just skip this "softer" block. I drive this car out on trips and play with it a lot, the last thing I need to do is break the block when I'm 8 hours from home.

Steve[/QUOTE]

Hey Marty, you been seeing my boy, Micah, Lately? Oh, Thanks for the advise.


Steve Prudhomme

Yes he a good man.

Steve,

If it were me and I was building a good street motor N/A, I would buy it in a minute. That is where the other two blocks went.

But you will be adding a power adder and that is where only you can make that decision.

When you make that kind of power it is like a good feel that just won't stop and you want more and then you want more.

Allpontiac has always stood by its products and will not sell a product with out fully informing the customer as to what they have.

These blocks were made by the foundry by there mistake. We offer them to a customer because some of them just will not build 1k H.P. and want something that is a upgrade but not a Monster of a motor. This is a cost savings.

The other thread was talking about a replacement block made cheaper, is not something that we found we can do. It is the same casting, sand, mold assembly, Shipping and machine work to make a better replacement block or a race block.

This is a one time offer and will never be offered again.

Bob, I will contact you a little later.


Steve

[/QUOTE]

So very true Marty, as you well know.
BOOST IS ADDICTIVE! YOU WILL START OUT SAYING IN GOOD FAITH THAT I WILL NOT GO OVER 800 HP. Then the Boost Fever comes and you want 1000 hp or more.

Agree with the NA deal not being as big of an issue because you can't add 300 more hp with just the turn of a screw or pulley change like a boosted deal.

Buy the better block in the beginning for boost.

Tom V.

Tom, you and Marty pushed me into a new block, Thanks? :)

Steve

It sounds like you are making a good decision.

Calvin Hill
Hill Performance
708-250-7420