Porosity Issues in High Pressure DieCasting of Engine Blocks

Performance modifications, tips & tricks

Moderators: flyingpolarbear, Dev, James B.

Post Reply
1999 Tahoe 4x4
Posts: 764
Joined: Sat Dec 15, 2007 2:00 pm
Location: Torrance, CA

Porosity Issues in High Pressure DieCasting of Engine Blocks

Post by 1999 Tahoe 4x4 »

I started a thread here ( http://www.pacificp.com/forum/viewtopic.php?t=14460 ) and within that thread kind of indirectly came to or referred to High Pressure Die Casting of engine blocks. It is an interesting subject that I was not aware of until recently and that I’m actively researching with great interest. That is why I decided to make a separate thread for it and merge in some of the info, hoping to broaden the discussion.

Apparently these days High Pressure Die Cast engine blocks are getting more and more popular. Indeed according to page 16 of this document ( https://www.european-aluminium.eu/media ... blocks.pdf ) most of today’s open deck engines are made using High Pressure Die Casting. From what I read so far, I believe that manufacturers may prefer this method for cost saving reasons and for being able to produce engines with reduced weight and thereby possibly able claim corresponding fuel savings.

However High Pressure Die Casting seems to have it’s issues as well, with the main one being porosity. That is my the main reason for posting this topic. I simply like to see and discuss more information on it.


A good example for die-casting porosity issues and sealant repair:
https://www.godfreywing.com/blog/3-type ... g-porosity

Video about the sealing process:
https://vimeo.com/225297533?__hssc=1637 ... 54673279dd

Another great read on the topic:
https://www.starrapid.com/blog/porosity ... ontrol-it/

It would be interesting to know how permanent such sealants are that used for the sealing process. I suppose manufacturers will claim them to be effective for a "lifetime", but as we know that definition can vary widely.

From what I read here, Toyota has already used High Pressure DieCast engine blocks as early as since 2000 in their AZ engine line:
[..."The cylinder block is an open-deck, midi-skirt die-cast aluminium type with cast-in iron liners and a die-cast aluminium lower crankcase"...]

A great video of a Toyota visually leaking oil, presumably because of porosity of the cast:

High Pressure Die Cast first seem to have been used in the US by AMC in 1961:

Posts: 1167
Joined: Fri Oct 27, 2006 7:32 pm
Location: Waikikamukau

Post by 97k15004wd »

That is an interesting read. At the end the mention on the mag/alum blocks being much lighter is pretty cool. I just wonder how longer the ICE is going to last in cars with everything going to batteries.

Posts: 10763
Joined: Fri Apr 30, 1999 9:12 pm
Location: 2021 Dodge Durango R/T 2WD, 2008 Colorado work beater, 2003 Dodge Dakota pro-touring project

Post by Speeder »

They could last quite a bit longer if they would be sensible and start making serial hybrids. We have everything in place for full electric except electrical energy generation and storage. Breeder reactors could provide the electricity and they are safe enough, but storage continues to be a problem. The serial hybrid could allow 100MPG cars that could bridge the gap between ICE and all electric.

Post Reply