I've got a line on a built short block I'd like to pick up. It's a great deal, but the block is half filled with block filler. Just about everyone I've talked to said it should act fine on the street and highway, but nobody has ever acutally driven a car with a filled block on the street. I'm going to make over 1000 at the flywheel on my next motor so it's certainly not a bad idea, but how is the streetability? One trusted source told me that some cars see higher oil temps with filled blocks. I need to be able to drive my car on the street and highway and take it on Power Tour or a road trip if I want.

-Chris

 

Its an LT1 383 right? It will be fine. Nearly all of the heat is concentrated in the heads and first half of bore travel. There's pleanty of traditional small blocks out there with hardblok up to the bottom of the waterpump holes without trouble.

 

Thanks, Mark.

-Chris

 

If it's done right it will be OK. Running one with no problems.

 

That's how I run mine.

Rich

 

Oil temp is up, (which is good), and water temp is exactly the same. That's the results from the 1st block I ever ran with a small bit of block fill, (up to the bottom of the freeze plugs).

This is in a street 383 LT1 engine. I'm thinking about doing more engines that way.

Knock sensors probably read inaccurate though.

Karl Ellwein

 

I have run half filled LT1 blocks for years on the street with no problems. You should be fine.

Tony Shepherd

 

Same here, just adds more stability to the bottom of the bores.

Bret

 

I'll second that notion, well maybe more like fifth but you get the idea.

I have run blocks filled as much as half and had zero issues with streetability. Like Bret said above, if anything it adds some structural integrity to the bottom of the block/bore.

 

Hey, can I piggy back a related question...? Thanks.

Anyone have experience with a slightly filled block and the effect on knock sensors? I'm venturing into the unknown on this. I have my PCM tuned way down for my junk but this motor I'm concerned about is going in a customers car and he may not be as in tune to the lug sound.


Karl Ellwein

 

This is only a wild guess, so its probably not worth much but the knock sensor response might be more accurate with a filled block assuming there wasn't much air included in the mix. I take it the LTx sensor is screwed into the bottom of the block? The block filler should reduce resonance some like dynamat does on a panel and help filter out some of the lower amplitude noise that can confuse a knock sensor.

Hey, its only a hypothesis. Try tuning the filled engine to induce audible knock and scan the results?

 

Thanks Mark for the idea. Yea, the sensors are an the very bottom, (LT1), and when I filled I stuck a little stick or something in there to make sure I had a channel for water drain and room for the tip of the knock sensor. I'm street testing this motor right now and it is seeing massive knock counts and although I'm not hearing it I ceratinly cannot be certain that it's "false". I've got a lot of research and testing to do on this because I LOVE the stability that little bit of fill provides and it's so cheap and easy. And I like how the oil temp is a bit higher and water temp is the same.

Anyone have a motor running knock sensors and some fill?

karl

 

Im new to this block filler stuff. Any info posted around on where to buy / how to use it? I have a new engine coming and if its smart to do it sounds like something to try.

 

It is a grout with brand names like Hard Blok. I get the small Moroso jugs just for ease of storage.

You always fill the water jackets "before" the block is machined keep that in mind.

Pour it in the water jackets and it sorta makes the cylinder case, (block), one solid piece. A short fill or 1/2 fill is just putting some at the very bottom of the water jacket up to around the freeze plugs. That at least adds stability to the bottom of the cylinders.

http://www.hardblok.com/ gives a good sales pitch.

hth Karl Ellwein

 

I have a traditional sbc with block filler to the water pump holes.. I've only got a couple weeks drive time on it back and forth to work ect.. everything seems fine. I did install and external oil cooler though.