VW / Chevy 8 cylinder open source project.

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RJW

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The "inline" radial is an old idea.
Dan,

I’ve always liked the 7755. But the Curtis Chieftain article is really very good. Thanks. It explores a lot of the advantages and disadvantages of in-line and conventional radials. You seem to be the guy to take a crack at a 10 or 14 cylinder inline VW/Chevy-based radial. If a 10-cylinder VW costs more than 1000 bucks then it isn’t worth pursuing. Take a crack at it. It would be gobs of fun. What do you say?

Rob
 

Dan Thomas

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Dan,

I’ve always liked the 7755. But the Curtis Chieftain article is really very good. Thanks. It explores a lot of the advantages and disadvantages of in-line and conventional radials. You seem to be the guy to take a crack at a 10 or 14 cylinder inline VW/Chevy-based radial. If a 10-cylinder VW costs more than 1000 bucks then it isn’t worth pursuing. Take a crack at it. It would be gobs of fun. What do you say?

Rob
At 59 I'm getting past the adventuresome stage. I have built many non-aviation machines that worked well, and still tinker with smaller projects, but with all my machining and welding and aircraft maintenance experience I know that 59 years old is perhaps ok for starting to build a reasonable homebuilt but a really bad time to start developing an engine. One only lives so long, you know, and there's little point spending time on something that will probably never get completed and will eat up everything I own. Seen it happen.

I am often amazed at some old guys who have a yard (or acreage) full of old cars and trucks and sometimes airplanes that sit rotting away and they won't part with them. Gonna restore them someday, they say. Yeah, right. At 70 years old? Life is short; the 40 years since I left high school have shot past in an unbelievable blur. You younger guys might take note, and make the best of the years you might have. There are things I would have done differently, now.

Dan
 

Dan Thomas

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Most of the commercially available VW conversions will run you $6K.
And that's with all the parts in the box, or maybe even assembled already. Building an engine using bits from here and there and having to create a crankcase and all the accessory gearing to drive the camshaft and ignition and oil pump and so on, takes a lot more than $1K. And radial cam drives are complex, indeed. No camshaft, but cam rings driven by fancy gearsets.



Dan
 

RJW

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The thousand bucks I mentioned would be used to buy stock or aftermarket parts from other manufactures to assemble a test motor. This would be the majority of the engine parts. I already have a lot of this stuff, picked up here and there over the years. I was not referring to the cost of a finished consumer product.

I see this thing as using the absolute minimum of custom parts. Some of the stuff that would have to be made would be the crankcase, the master and slave rods, counterweights for balancing, the prop shaft and support, induction and exhaust, some kind of ignition system, and other smaller stuff.

Also, the idea is to use stock VW camshafts lifters etc. No difficult cam rings and drives. The stock cams could be gear or chain driven. I was thinking a chain might be best/easiest.

I have wasted more time again on this in the last few days (been working on the idea here and there for four or five years). I’ll spend a little more time on the crankcase today. If I come up with something that looks sort of doable then I’ll post a pic.

And Dan, you are right. I’m 50 and probably should be spending my time finishing up some of the projects that I’ve been hauling around for years—one of which I picked up when I was 15! Maybe now isn’t the best time to develop a heavy and kind of crappy, cheap radial. Still, the idea seems fun right now.

Rob
 

dirk_D

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Rob, if you do get a frankenstein motor on the bench, be sure to share a build log with us please?
I'll agree with Dan that time is a factor, just lost 2 weeks of my spare timing doing other stuff like house repairs, computer repairs.

Reading forums can take a whole afternoon or an evening!!!!!!!:gig:
 

dirk_D

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Oh my, forget the boxer - here is a new direction.
An inverted, air cooled V8 for Storch replicas based on VW and Chevy parts?

I got the idea when researching low airspeed landings (Australia - 45knots - Delta design in the waste paper basket)

This one would be the go, lots of people have a soft spot for those 'storks'.
 

Toobuilder

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... One only lives so long, you know, and there's little point spending time on something that will probably never get completed and will eat up everything I own. Seen it happen...

...I am often amazed at some old guys who have a yard (or acreage) full of old cars and trucks and sometimes airplanes that sit rotting away and they won't part with them. Gonna restore them someday, they say. Yeah, right. At 70 years old? Life is short; the 40 years since I left high school have shot past in an unbelievable blur. You younger guys might take note, and make the best of the years you might have. There are things I would have done differently, now...

Don't know why I missed this post back in April, but it sure resonates! I'm 44 and am just now realizing I have more projects in the que than I will ever finish. That's why the Starduster is now on the way to a new owner, my Mooney is on eBay, and 3 of my cars are soon to follow. That will leave me "only" 2 cars and 2 airplanes to build. (until I find more). The time does go fast though - when I was 20 (seems like just yesterday), I couldn't make time go fast enough. These days I'm trying desperately to get it to slow down! Months pass in the blink of an eye. I heard once that age is like the numbers on a speedometer - the older you get, the faster life passes by.

Got to focus and enjoy life while we can!

Sorry for the "off topic" rant...
 

Jan Carlsson

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I got a good explanation why the years goes faster and faster the older we get, it is because the last year is a smaller % of the years we have lived when we are older, then what it was when we was kids.
 

cheapracer

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To get rid of lots of time and money. Many folks have already spent lots of time and money on developing new engines that never reached the market. Most of them never flew in an airplane. Some of them never even made any noise.

Dan
The vibration might or might not cause problems. Don't know. But it wouldn't be very smooth in any case, and I suspect that the "fun and cheap" part would disappear pretty quick, too.

dan
I bought 3 engines the other day, a few hundred bucks down the drain and now I'm going to waste plenty of my time experimenting with them for most likely no result.

To quote Maxwell Smart ...

... and loving it. But then, I've got a life, and a fun one at that.


I think the answer for a flat 8 VW with the exhaust port problem is obvious, take the drive off the center of the crankshaft so you got basically 2 flat 4s joined in the middle but with a gap, takes the stress off a long crankshaft as well and that's what Mercedes Benz did with their racing straight 8 in the 1950s.

Even had a quill shaft ..

450259_754529_4800_3822_590433a2003f4238.jpg
 

RJW

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I think the answer for a flat 8 VW with the exhaust port problem is obvious...
That’s right. But the original idea, way back in 2012, was to use a stock SBC crank.

Keep fooling with actual motors. It is much more fun than sitting in front of a computer screen. I too get a big kick out of making wierd stuff out of perfectly good motors.;)

Rob
 

cheapracer

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Also to balance a 90-degree V8 crank a LOT of extra mass is needed. The use of a 90-degree crank in a flat 8 engine would wipe out the inherent balance and light weight of the 180-degree flat 8 configuration.
Just a point, a few years on now and you can buy flat plane cranks, 2016 Ford Mustang GT350 for example.
 

ekimneirbo

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Oh my, forget the boxer - here is a new direction.
An inverted, air cooled V8 for Storch replicas based on VW and Chevy parts?

I got the idea when researching low airspeed landings (Australia - 45knots - Delta design in the waste paper basket)

This one would be the go, lots of people have a soft spot for those 'storks'.
The LS engines are a little heavy for most of the scaled down storch designs. The Hall brothers in Utah built a Pazmany

Storch and shoehorned a 6 cylinder aero engine into it. I don't remember which engine they used but they had to set

it back (9" ???) to maintain W/B. The Pazmany is a little heavier and stronger than some other versions.

You might move up to a Pegazair which can accomodate somewhat more weight and still STOL with the best of them.

Engine wise Steve Wittman was known for inverting the aluminum Oldsmobile engine and the newer Rovers are just

an improved version of that engine. More cubic inches same weight all aluminum....injection or carb. There are still

instructions available on inverting those engines.

http://pazmany.com/wp/?p=158
 

cheapracer

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the aluminum Oldsmobile engine and the newer Rovers are just

an improved version of that engine. More cubic inches same weight all aluminum....injection or carb.
Only the 2 bolt main 3500 is the same weight (160kgs for basic running engine)

The later ones, 3.9, 4.2 etc, are a bit heavier being taller blocks and extra ribbing, 15kgs from memory, and have 4 bolt mains (2 lateral bolts).

This is mine, no water pump or exhaust, 150 kgs exactly. To put that into perspective, there's not many 2.0 4 cylinders under that weight.
 

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Pops

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The Buick 215 cu aluminum block V8 engine of 200 hp that I had in my 1968 VW bug was 75 lbs heaver than the stock 1600 cc VW engine, not counting the heavy cast Buick exhaust manifolds.

Dan
 
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