closed deck block for $50

[206er]

hmmm. its definitely a proven method in both the honda and V8 world. looks like an interesting thing to try.
cliff notes:
sand water jacket area to be filled
fill block with salt to desired level
fill with devcon liquid aluminum
machine work
hot tank
boost to 400whp then crack the sleeves(maybe open deck is more of an issue on the honda motor?).
http://www.honda-tech.com/zerothread?id=1444721&page=1

[vrg3]

Way back when I had my Impreza I was sort of considering doing this, but I couldn't find an epoxy with a thermal expansion coefficient similar to the aluminum that makes up the block.

The datasheet for that Devcon stuff lists a typical alpha of 50 10^-6/degF. Aluminum alloys generally have an alpha of about a fifth of that.

I wasn't aware that it was well-proven in non-drag-race applications though. Is the thermal expansion somehow a non-issue?

[206er]

from what I can gather from that thread, the OP was adamant that detonation was the cause from a bad batch of gas. and that may be the case, but maybe it was that there were combustion chamber hot spots from the devcon insulating the sleeve which aided detonation.
the thread on nasioc where I found this, someone alluded to running fully closed deck(no passages) motors on the street with external cooling lines to the head.
I think this is still a great idea, but maybe a little more care needs to be taken in how the devcon is added. ie form some passages against the sleeves, and only fill the middle portion of the sleeve allowing the hotter upper sleeve to transfer heat as people are talking about towards the end of the thread.
vikash, moroso makes a specific grout for block reinforcing though it is targeted to V8 drag cars, and is meant to reinforce the main bearing saddles. there is an aluminum and an iron version, containing actual aluminum dust or iron dust in the mix to very closely replicate the expansion.
as far as being well proven, I guess "well" might not be the word for it, just a couple people who responded in that thread saying that they had been abusing a filled D-series on the street for 3 years. and plenty of people run rock blocked V8's on the street as it doesnt interfere with sleeve cooling, as its down low. though I suppose that does not really prove anything about sleeving does it.

[vrg3]

from what I can gather from that thread, the OP was adamant that detonation was the cause from a bad batch of gas.

The cause of what? Cylinder wall deformation?

It's true that even the best tune can't guarantee a street car won't detonate, because you can't promise you'll never get some bad fuel.

and that may be the case, but maybe it was that there were combustion chamber hot spots from the devcon insulating the sleeve which aided detonation.

Yeah...

someone alluded to running fully closed deck(no passages) motors on the street with external cooling lines to the head.

Seems a little nutty to me, but I guess air-cooled engines only have cooling fins on the heads. That seems to be out of necessity though.

I think this is still a great idea, but maybe a little more care needs to be taken in how the devcon is added. ie form some passages against the sleeves, and only fill the middle portion of the sleeve allowing the hotter upper sleeve to transfer heat as people are talking about towards the end of the thread.

Oh. I didn't read through the thread. Yeah, that might make some sense. Approximating a semi-closed block, kind of.

moroso makes a specific grout for block reinforcing though it is targeted to V8 drag cars, and is meant to reinforce the main bearing saddles. there is an aluminum and an iron version, containing actual aluminum dust or iron dust in the mix to very closely replicate the expansion.

Well, the Devcon stuff contains aluminum dust too. But if Moroso says it matches the thermal expansion coefficient, I would definitely use that stuff instead of any other kind of epoxy.

as far as being well proven, I guess "well" might not be the word for it, just a couple people who responded in that thread saying that they had been abusing a filled D-series on the street for 3 years.

Hm. That impresses me, especially if it was this epoxy rather than the stuff made for the purpose. I wonder if there's anything particular to the Honda D block that might make it especially receptive to this modification.

and plenty of people run rock blocked V8's on the street as it doesnt interfere with sleeve cooling, as its down low.

But do those engines have the same kind of specific output that high-power Hondas and Subarus have? I would imagine they don't, so they wouldn't have quite the same concentration of heat.

[sammydafish]

they arn't filling the whole block, just about an inch at the top of it to stabilize the sleves. Kinda like this http://www.cgperformance.com/subaru_block.htm

The water still flows and the cylinder is still cooled. Granted the hottest spot of the cylinder isn't but that's something you need to give up for the strength.


I wonder if you did basicaly the same thing, but payed the epoxy in about a half inch from the top. You would still stabalize the sleves, and have water flowing around the top of the cylinder. Thoughts?

[vrg3]

Yeah, I think that's what Jeremy is suggesting when he says to fill the middle portion. I agree that it seems like it might be a good idea.