Subaru Engine Conversion Comparison

20 Sep 2004 Subaru Engine Conversion Comparison

Update 20210918: I didn’t install the Eggenfellner Subaru engine, so any post that references that can be ignored or used as a cautionary tale about how to avoid wasting many years and $50k.

I’ve chosen the Eggenfellner Subaru 2.5XT supercharged engine for my airplane. Here is how I decided to purchase the Eggenfellner. First, price was not a consideration. I didn’t compare prices before, during, or even after I made the decision. I knew it would be expensive, no matter which engine I chose, so as they say, “if you have to ask the price, you can’t afford it.” Of course, that’s BS, but it sounds good.
I contacted NSI, Crossflow, and Eggenfellner after reading as much as I can about all three on the web. I also read as much as I could on various internet news groups as I could. Eggenfellner has a Yahoo news group where customers and prospects exchange ideas, ask questions, and discuss the engine package. It is controlled by Eggenfellner, so it should not be considered a totally objective source of information, but there is a lot of information in any case. Interestingly, I’ve discovered that customers can post anything they like and they are never censored, and in fact, their posts are not approved by Eggenfellner – they go right up. Prospects’ postings are approved or rejected. This prevents people that are not committed to the engine from posting negative comments, and of course keeps out spam.

NSI has a web site with a lot of information, but there are a lot of dead links, and it does not seem to be maintained. Kind of a shame, since their product looks good. I could not find a dedicated news group for the NSI or Crossflow engines, but the group E-SubieForum seems to have some NSI fans, and to the best of my knowledge, no one that has purchased an NSI engine, but I might be wrong.

Crossflow has an excellent web site that has been recently updated.

When I contacted all three suppliers, I got immediate feedback via E-mail from both Crossflow and Eggenfellner. I didn’t get anything from NSI. I also tried faxing and telephoning NSI, but I never got a response. This was a major disappointment, since after reading the websites, I was really not sure which engine to purchase, and I needed more information. Not hearing from NSI themselves, I sought NSI engine package owners, and I found a lot of them in the Glastar community. I sent an E-mail to every one, about 40-50, and got feedback from most. There were a couple of guys that mentioned they had problems, but overall everyone was happy with the package.

I got lots of details from both Crossflow and Eggenfellner. The proposal that Crossflow sent was really world-class. Truly professional, and something the other engine suppliers should try to emulate. Since I could not get any response from NSI, I figured that during my trip to Sun ‘n Fun 2004 I could meet them face to face and get answers. Unfortunately, they didn’t go to SNF. I had to take their engine out of competition, regretfully, but I didn’t have much choice. I felt that if I could not get information from them before I sent my money, what would happen if I needed support down the road?

Now, I focused my attention on Crossflow and Eggenfellner.

Both Jan Eggenfellner and Tony Howard of Crossflow were really great at answering any questions that I posed to them. I also was able to get a lot of feedback from current owners of the Eggenfellner package on his Yahoo group. This quick feedback from lots of RV builders flying or installing an Eggenfellner was a huge plus.

After getting my questions answered, I then had to make a choice. I was really happy to have a difficult choice to make, since both packages seemed very solid, and the company behind each of them was well-regarded. I found people with experience with the package that said that they were great, and they were very happy with the support they received from their respective factories. The decision was getting tough.

In the end, it came down to two things that helped me decide for Eggenfellner.

1) Eggenfellner does not open the engine, or modify it in any way. I liked this because I have a lot more confidence in the quality control of Fuji Heavy Industries than any small (less than 1000 employee) shop. This is not meant in any way to disparage the quality and quality control of the Crossflow team, and I am sure that they do excellent work. I just feel more comfortable with an engine that was last opened at the factory.

2) I would be the first RV8 customer for Crossflow. This would not have been an issue for me if I lived in North America, since getting support/parts/etc from the factory would be easy, cheap, and quick. However, being in Switzerland, it would have probably added a lot of time to the project, time that I can’t afford. Crossflow was willing to send someone out to help me get the engine installed, which would have helped a lot. I just didn’t feel comfortable being the first for something like this.

Not sure if this information will help anyone else, but that’s how I decided.

Update 20051227: It really seems like I made the right decision. NSI has gone out of business, and is in the process of being resurrected by some investors. Not sure what the future holds for them. Crossflow has not delivered engines to at least two builders that I know of, even after full payment. Very disturbing. I’m really glad I chose Eggenfellner!