Hard Block

Has anyone used hard block or a block filler for they're race engines?? If so how does it work and is it a good idea?

I have block filler in my 500 inch BB. I bought it that way, Not sure I would of did it that way. I have had no problems though in 6 years with over heating or anything. I have only about 4000 miles in that time. The car is a driver in the heat of the day with no problems. I don't regret it now after the years its all good.

I have hard blok filler in my stroker 408 small block. It is used to strengthen the block. I have run the car for over a year at the track and have had no issues with the engine over heating. Dyno was done on engine after build. 611 hp @ 6400 rpm and 546 ftlbs of toque. :)

just dont put too much in, i have seen guys overfill them and ruin a perfectly good block.
it all depends on how much power you plan on making.if your making under 700 hp, i would not use it.imo
if you run it on the street, i definitely would not use it either.

Has anyone used hard block or a block filler for they're race engines?? If so how does it work and is it a good idea?

If you go that route fill the water jacket, before it goes to the machine shop for boring or honing, the expansion of the filler can distort the cylinders & effect ring seal, Also only fill below the freeze plugs & use a vibration device of some sort (I used a hammer drill with a rubber pad on the side of the block) to get all the air out of the cement/filler before it starts to cures... I wouldn't do it for a street engine but I know people that have with success...

Hard blocking is a cheap way to strenghten a factory block. Not every one can afford a new aftermarket block. We fill them just above the brass freeze plugs. That and a main cap girdle will fine up to 750 hp.

If you go that route fill the water jacket, before it goes to the machine shop for boring or honing, the expansion of the filler can distort the cylinders & effect ring seal, Also only fill to below the freeze plugs & use a vibration device of some sort (I used a hammer drill with a rubber pad on the side of the block) to get all the air out of the cement/filler before it starts to cures... I wouldn't do it for a street engine but I know people that have with success... Just a suggestion the girdle is a great idea

I did one just above freeze plugs becuse of a cracked block from freezing. run it on the street for three yr.myself sold the motor and he raced it for two before blowing it up.........Artie

was curious have a 400 that I would like to make into an all out race stroker....h beams, billet crank, etc....wondering if it would save some headache later on

Yes it could stiffen it up some...