Vintage Engine Tricks

[dmar836]

No offense to others but I have never fallen into the bigger engine, more battery, more starter, more glass mode of sport aviation. Neat stuff for sure but, especially for SV, adds cost, complexity, and worse, weight! I've seen many projects that could be done by now if not for "now's the best time to do so I'll just add..."
Back on topic, I have submerged myself in VW tech for about 2 months and see it's gone a similar route.
I have built numerous engines(V8, many 2-strokes, BMW boxer) but never a VW. Great vintage tech and I feel no fear to give it a go when needed but I'm wondering what the "recipes" were in the day. Obviously, for FV VW marked internals but carbs, porting, exhaust? Will the secrets be kept forever? How about common areas of failure back then? I plan a stock 1600cc but might add a cheater cam and lightly port some stock or "factory replacement" heads. Stock valve sizes, 1.1:1 rockers, etc. Under carbing it is a real fear. My project came with a mag so I'll stick with that.
I've heard the "just get an AeroVee or GPAS" argument and understand but I'd like to build a small engine as originally intended.
Any ideas on small displacement engines ?
Dave
Kansas City

[Supervee]

Dave, I am an airframe guy, not an engine guy…so take that into account….I agree, "ADD LIGHTNESS" was what I have always believed in. My opinion only…If I had to think of the best engine men involved in Formula Vee in the old days, I would have two names….Rick Leonard, and Charlie Terry…Sadly, both gone now, but they approached the FV engine rules in a different way from each other, but they both got to the finish line together…Rick had an interesting take on the FV rules….As these engines were pounding themselves to death, when higher compression ratios were used, his angle was to use the stronger Type 4 case, with the 1600c.c. outer end. Charlie's Approach was different…The standard type one or type three case, and he preferred to use 'seasoned' cases, he said…ones that had driven in cars…These guys got good horsepower out of the 1600….
For me, as a designer, and builder, I like to get the best performance out of the smallest engine approved for the design. My Sonerai #14 will probably use the 1600, possibly the 1700….
Will be interesting to see what you come up with….Right now I am searching thru all my stuff to see if I still have the original Formula Vee engine rules, because we are going to need them for our Supervee "FV" class…….I wish I could have learned some of Charlie's secrets before he left us…Ed

[Supervee]

Re-read your post, Dave…….The 'Secret' in FV engines…….One that would just bring a 'smile' from a competitor when the question was asked…..."Compression Ratio" or..How Big were the Valves?…….Quiet smiles would be the answer I got…...

[Supervee]

I have a note out to the last FV champion, and president, Dave Patterson..(#88 ) to see if he still has any copies of the original FV engine rules…I believe mine were lost in a fire in 2011…..

[dmar836]

Thanks Ed. I guess we know a lightened stocker works based on Wittmans early success. Reliability is my concern once airborne so I doubt I would want to venture over 4500rpm. I know that the powerband of a car and a constant rpm application is quite different. Without discrediting the mainstays in VW "aircraft" engines, it appears that displacement has been the main way to increase HP. Other engine parts are understandably pretty mild in the street world. Getting that flat but elevated torque curve with basically stock internals should be fun.
Without easy access to a dyno and adding in prop variations, I just hate to reinvent the wheel.
There is precious little on the web about aircraft application and the consensus is to withhold the application from any vendor lest you be blacklisted.
Dave

[Supervee]

I like the VW because the west coast Dune buggy and 'Hot VW' crowd created companies around their products. And, there are lots of products available. Its still tons cheaper to build a new VW than it is to overhaul a Continental C-85 or 0-200.
In the heyday of FV racing, I remember 4200 rpm was a good number to shoot for…I have Beetlebombs race prop here, it is 48" in diameter….
I encourage you to build up an engine and do some experimenting. With your past experience the VW should be easy to do…..

[dmar836]

So here's one:
Are the copper lines on Wittman's V-Witt and on #33 Chasin' Rainbows not oil cooler lines? I know both Jim and Ed worked quite a bit on Jim's #33. I'd be interested to hear discussion about those lines as opposed to an underbelly oil cooler. Certainly not appropriate for a Sonerai but a lot of space for this on the V-Witt. My cast cone has the threaded holes along the sides as did Steve's original welded cone. I like the look!

[Supervee]

Yes, they are oil cooling lines. The picture of Jims V-witt front end here is in my hangar, before we found a wing problem. I believe Jim completely re-did FWF after this picture at some time......Don't know if he retained oil cooler lines, or just installed a standard cooler.....

[chuckerf14]

Hey Dave,

Here is what I did:

I kept the stock dual port heads and valves but did some minor porting and polishing. I think that bigger valves just result in slow port velocities.
I am running a compression ratio of 8.5:1. The 2100D (Revmaster) started at 9.4:1. I am being a little more conservative.
If I get serious about going fast, I will need a smaller prop. My daily driver prop is a Sterba 54-46.
When you run at one RPM all day, magic ignitions can perform no magic. I have a Bendix dual magneto and that is what I will always run....unless I go to a single magneto, single ignition.

As Ed alluded, RPM and compression are the two major keys to getting more power. Of course, there is no replacement for displacement.... But that would put you in a different class of racing.

All the best,
Chucker