Gordon wrote: With all the negative posts on the VW I am starting to get a little "gun shy" about the VW's in general and I haven't even flown mine yet.
Gordon - I debated a lot before replying to this post, and I'm trying not to "poison the well" so I will not go into all the gory details in public. But my experience with a VW engine kit so far can be summarized like this:
I used to be involved in auto-racing (both NASCAR and SCCA), and I've assisted with some 4-cylinder and V8 engine builds. I am by no means an expert, but I understand engines and am not intimidated by them. From that experience and in my opinion, there's no reason why a VW-conversion engine won't work as a simple and effective aircraft powerplant. There *are* differences, however, between the various purveyors of conversion engines and kits.
With any of the VW conversions that don't come to you as already assembled and test-run, you
need to treat it like a second "homebuilt" project you are taking on. Regardless of the sales literature or the webinars you've seen, treat a VW "engine" as just a bunch of parts that have been conveniently repackaged and shipped to you in fewer boxes. Nothing more, nothing less. Do NOT assume that those parts have been checked or inspected by the people you bought them from - it is quite possible that even "brand new" components were sourced by 3rd parties, stocked on a shelf without being opened, and then shipped to you. If you blindly assume the items are good and assemble the engine, you risk using mis-machined parts, installing items that have been substituted by 3rd parties without the engine purveyor's knowledge, or having items that are used/corroded (either through a stocking mistake or due to fraud somewhere in the supply chain). And yes, sadly I can speak from personal experience on all 3 of those.
Therefore, if you buy an engine or engine-kit you need to learn how a VW engine works, understand what the proper tolerances are, and what a "good" part should look like for every engine system/component. Treat it as another "homebuilt" project you're doing from the ground up. You should not assume that every part given to you is correct and that you simply have to follow a manual to result in a safe and properly functioning engine. Its true that many have people have blindly assembled a VW conversion and wound up with GREAT engines! As I said, the products appear to be solid when every component is correct and they all come together properly. But other people have had very different results, so the only way to be sure is to ignore the marketing and sales claims of these things being sold as "Engines", or to think that they require no knowledge of Engines or the VW in particular. Treat them as buckets of parts that you're buying as a bundle, instead of trying to source from 12 different suppliers yourself. The requisite knowledge is not hard to learn and anyone with average mechanical skills can do it - but you have to go into it with your eyes open and a willingness to spend the time and effort to learn.
Again: You must take responsibility for understanding and inspecting each and every thing yourself or your risk frustration and a powerplant with questionable reliability. Now that I've assembled and run one, if I were to do it over I would strongly consider buying a complete and running engine instead. Knowing that someone with expert VW experience assembled the parts and ran them at their facility is a lot more confidence-inspiring (and a lot less frustration-inducing) than finding out that I've been shipped a bunch of parts that no one inspected before sending them out to a customer.
Take care,
--Noel