# What happened to Plastic engine blocks? **URL:** \ **Category:** Miscellaneous and Personal Stuff I Must Share\ **Created:** [January 28, 2009, 4:07pm UTC](https://boards.straightdope.com/t/what-happened-to-plastic-engine-blocks/483388 "2009-01-28T16:07:59Z")\ **Posts on this page:** 4\ **Page:** 1
**Author:** ![ralph124c](https://avatars.discourse-cdn.com/v4/letter/r/8797f3/32.png) [@ralph124c](https://boards.straightdope.com/u/ralph124c)\ **Post date:** [January 28, 2009, 4:07pm UTC](https://boards.straightdope.com/t/what-happened-to-plastic-engine-blocks/483388/1 "2009-01-28T16:07:59Z")
Years ago, I read about a NJ firm, that was going to mass-produce car engine blocks out of a high-tmperature plastic compound. The idea was to save a lot of weight, and also, the blosks would nedd to machhining-they could be injected molded. Plus, they would be extremely cheap to produce-about 20% of the cost of an aluminum block. Well, needless to say, it didn’t pan out. I think the company name was “polymotor”-anyone know more? ---
**Author:** ![Who\_me\_1](https://avatars.discourse-cdn.com/v4/letter/w/958977/32.png) [@Who\_me\_1](https://boards.straightdope.com/u/Who_me_1)\ **Post date:** [January 28, 2009, 4:26pm UTC](https://boards.straightdope.com/t/what-happened-to-plastic-engine-blocks/483388/2 "2009-01-28T16:26:11Z")
Apparently they didn’t work out. > **[Plastic automotive engine](https://en.wikipedia.org/wiki/Plastic_engine)** > > The Plastic automotive engine has its origins in the late 1970s with research and work done by Matthew (Matti) Holtzberg of Polimotor Research and his associates. Since then Holtzberg and others have done steady work in the field. > Matti Holtzberg first attempted to make polymer pistons for an Austin Mini engine in 1969. The pistons ran for only 20 minutes until failure. Holtzberg remedied this by fitting the pistons with aluminium crowns and he sold these pistons to racing builders during the ea... ---
**Author:** ![kenobi\_65](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/kenobi_65/32/13178_2.png) [@kenobi\_65](https://boards.straightdope.com/u/kenobi_65)\ **Post date:** [January 28, 2009, 4:29pm UTC](https://boards.straightdope.com/t/what-happened-to-plastic-engine-blocks/483388/3 "2009-01-28T16:29:29Z")
Unfortunately, that Wikipedia article says nothing as to _why_ plastic engines were considered to be a failure. 😛 ---
**Author:** ![Philster](https://avatars.discourse-cdn.com/v4/letter/p/13edae/32.png) [@Philster](https://boards.straightdope.com/u/Philster)\ **Post date:** [January 28, 2009, 4:30pm UTC](https://boards.straightdope.com/t/what-happened-to-plastic-engine-blocks/483388/4 "2009-01-28T16:30:13Z")
The R & D money was required someplace else. Seems like there was potential, but there is a long ‘return on investment’ and with all the pressures in the industry, they were spending millions (I would guess) to drop 150 lbs from the vehicle?