Well we still don't have are new motor and we had to make a race so we decided to throw the old motor in.As there was a old post about pushing water and lifting heads we proved the problem.We tryed diffrenet head gaskets and torque metheds.I always said the bores move way to much that is the cause for pushing water.So we hard blocked it.One thing i was worryed about was cooling although we filled only to the bottm of the water inlet so you still have upper cylinder and head cooling.The result was i did not push a drop of water compare to not being hard block it would push about three quarts.Water temp after a pass was 160 vs 230 without hard block.Motor still takes some time to warm up as i thought it would really be fussy with cooling.We had a 31 in the DP and ran it to third gear and shut it down so we could read plugs.We still coasted through the traps at 9.21 with a 125.00mph.I figure i would share my experance with the whole pushing water to not pushing a drop.I was very impressed with the results.

 

Thanks for posting your experience. This has beened noted for future reference. ....................................... Seriously, thank you, Rick.

 

What does hard blocking mean???????????

 

Filling the block with block filler.

 

Sounds good. the turbo guys do this and run the copper gaskets/o-rings as they have proven to reseal even after lifting, so no tear down and rebuild needed. So with the biggest hits, you could still pressurize the radiator and blow a gasket out. Maybe the ultimate answer will be filling the block, an iron block, copper gasket and receiver groove in the iron rather than aluminum to maintain integrity. I was just thinking tonight about how i could log radiator pressure. Maybe run some sort of relief valve when pressure gets to high into a puke can. I will be hitting mine soon with a 350, so will be getting into pushing territory, though no block filling for me, lol. You know, you could isolate the water completely from the the lower end and still get some cooling. Exactly how, well still working, or rather thinking on that one, but have some ideas.
Robert

 

Come on, some of you techies must have some insight?
Robert

 

You are using the iron block? 408
I never thought the .030 overbore was an issue on the iron blocks, But if your saying hardblocking helped with bore shifting I have to wonder if staying stock bore might help even more. And how can the bore shift in the iron blocks?

 

Robert couldn't you just put a pressure sender fitting in a piece of pipe, replace a section of hose with the pipe and log the pressure that way?

I have thought about this and when I tear my ls2 down this winter to freshen it up (providing it makes it that long, and everything is in good enough shape to not need replacing) I am going to fill the bottom portion of the motor with the cement. Now, my question is with the alum block, what can we use to fill it, the same hardblok stuff? I know that stuff is supposed to expand at the same rate as an iron block, but what about an alum block? Is there a block cement made for alum. blocks?


Another thought I have had to totally eliminate the head gasket/water issue, is to somehow have the heads blocked off as well as the deck, and plumb the water externally from the block to the back of the head where the freeze plugs are, then pump the water thru the heads to cool them that way, and just return it to the radiator back out thru the front freeze plug ports. Sure it would be a total pita, but would it work?

 

That's pretty much my thinking on the cooling, then we will have isolated water from the combustion chamber. Head lifting may still happen, but as long as the gasket will reseal, will it still be a major issue.
Robert

 

Did you use the stuff that you can find in a Summit magazine or something else?

 

So the best bet would be to fill the entire block and run alcohol?

 

Now you're talking

 

The Trans Am car the Mike Brown / Ohio boys run has a puke tank setup kind of like what you are talking about. It's mounted up high by the intake manifold.



EDIT:

The expansion tank works like this... The radiator cap is on the top. There is a -10 line on the bottom that feeds the top of the radiator. The 4 steam ports on the heads go near the top of the tank. The tank is filled near half way full of water. When the heads lift, the air that enters the system ends up at the top. It just gets pushed out and into my overflow tank. Ta-da

 

I run on alcohol not the motor!!!

 

Same stuff and it was filled to the bottom of the water jacket.

 

Could you use that same stuff with an alum block? I'm gonna have my car torn apart over the winter to freshen it up, I'd like to do this if there's anything to be gained.

Granted I haven'thad any problems but I'm doing little kid hits of nitrous, but still, while the motor is apart no better time.

 

Thanks

 

We were thinking that the aluminum blocks would be a great idea.If i did it again i would try a aluminum block and i would use the hard block.The right way is to fill the block and torque a head down on it and let it set up before doing the other side, Then have the block honed to get the bore straight from any distortion.I think it would be a stought piece.The other thing that was brought to my attenion was torqueing of the heads.Over touque is just as bad if not worse than what the fastener manufacture reccomends.I've heard of heads getting warped just from over torquing because of the distance between studs.The bores moving around in the ls blocks is just a huge problem.

 

Good info, Thanks.

 

You think that when I take my motor apart, I could fill the bottom 1/2 of the block before I have the machine shop run a hone thru the cylinders? I dunno if it would work like you're thinking.

Then again, if I'm only going to 150 to 200 woth of spray is it really a factor?