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Parts that don't exist:


Draco-REX

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You can see the block when you look straight on, and the center gear between the two larger gears has a clear view of the top. those are straight cut. It probably is just noisy. They could be using individual dampeners, or metal matrix gears?
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reminds me of the gear drives on Ironhead sportsters and Ducati Bevel Drives. You car guys are all kinds of spoiled with room to run fancy gear setups without double and triple stacking gears.

 

 

Ironhead sportster cam drive:

img_7122-copy.jpg

 

Bevel Ducati Desmodromic setup:

87b0ba792d5d9d8f402e99dbac6d616a.jpg

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I have to admit, I never thought of a gear-shaft drive for OHC/OHV applications...no chains/belts to break...makes sense for compact applications like motorcycles.

 

Actually Clay, Towershaft or bevel shaft cam drives were really popular in pre-war cars. The 1919-1929 Bently 3.0L was well known for this as well as having some other innovations (overhead cam, dual plugs per cylinder, 4 valves per cylinder, and twin carbs in 1919!!!!). I think there were some airplane engines that used it too.

 

It's a very British engine design as Velocette, Norton, Rudge all had the design in their lineup back in the 1930s as well as Bentley and MG. The only American manufacturer to use it was Crosley in the 1948 Cobra 4 cylinder engine (made until 1972 and powered everything from race cars to generators to boats).

 

I think the reason it is unpopular now is that it is expensive to manufacture and service, with large car engines you have the room to engineer straight mesh gears, and the technology has been outgrown due to advancements in belts and chains. The Kawasaki W800 (replacement for the W650) is the only bevel drive cam production vehicle I can think of (and they don't sell it in the states).

 

 

BTW....am I the only one who is perplexed as to why a pushrod engine like the sportster needs two seperate cams - one per cylinder? To put this in perspective big twin HDs are single cam until the TC88 engine of the early 2000's.

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BTW....am I the only one who is perplexed as to why a pushrod engine like the sportster needs two seperate cams - one per cylinder? To put this in perspective big twin HDs are single cam until the TC88 engine of the early 2000's.

 

I think it's actually 4 cams, 1 per cylinder per valve. From what I've read it has to do with the valve alignment in the head which is improved by keeping the pushrods parallel. Something about a holdover design from the old racers.

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I think it's actually 4 cams, 1 per cylinder per valve. From what I've read it has to do with the valve alignment in the head which is improved by keeping the pushrods parallel. Something about a holdover design from the old racers.

 

You are right, it is 4 cams...brain fart.

 

The "pushrods" angle makes sense since the XL sportster bottom end shares a design with the old K model flatheads. The cases all interchange (mostly). Anybody else impressed that the has these overlapping gear drives in 1954?

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Don't forget the 83' Corvette, no parts available at all for that car.

 

When you use an apostrophe in a year, it goes before the numbers because it's taking place of "19", so in this case it's '83.. unless you're talking about the model year 8300 Corvette, in which case you would be correct that no parts exist for those yet.

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Don't forget the 83' Corvette, no parts available at all for that car.

 

I was going to add that too, except there is ONE 1983 Corvette. It's at the Corvette museum (if they managed to fish it out of that sink hole). So technically, there are parts for an '83 Vette. All of them just happen to be ON the '83 Vette.

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I was at a Barrett Jackson auction a few years back and they auctioned off a 1983 station wagon they used to test the 1984 corvette motor and suspension. Went for ~10k, I always thought that would have been a cool buy.
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Although, could we not suppose that there are parts available for the single '83 Corvette, with GM technology that's interchangeable between 1982-84? If I grabbed a few alternators for 1982 and 1984 Corvettes, I'll bet one of them is a perfect fit for the '83...should it need a new alternator from sitting in a museum all these years.

 

Just because the car was not sold - since the public never could register an '83 Corvette - doesn't mean there aren't parts available for it...

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Although, could we not suppose that there are parts available for the single '83 Corvette, with GM technology that's interchangeable between 1982-84? If I grabbed a few alternators for 1982 and 1984 Corvettes, I'll bet one of them is a perfect fit for the '83...should it need a new alternator from sitting in a museum all these years.

 

Just because the car was not sold - since the public never could register an '83 Corvette - doesn't mean there aren't parts available for it...

 

the 1983 corvette is actually kind of an interesting thing in "corvette lore". Actually 43 pre-production 1983 C4 cars were built but only one survived. Why? Original sales of the c4 were supposed to begin in October 1982, but the state of California passed SB 33 which created their emissions reduction and smog check program. The C4's configuration was not set to meet these new emissions standards and the drive-line had to be re-engineered to accommodate new emissions controls. All pre-production cars were ordered to be destroyed, which pissed off the Chevrolet dealers because some of the cars had already been ordered by and allocated to dealers.

 

In the end Car #23 was saved because the employees of the assembly plant where the pre-production cars were built hid it in an effort to save it. Why? because it was the first "new model" corvette built at the bowling green facility and they felt a need to save one (corvette production in St. louis stopped in 1981 but the C3 finished out it's run being assembled in Bowling Green in 1982). They went through a lot of effort to save the car such as repainting it several times and disguising it as a testing mule until it was agreed that GM wouldn't destroy the last car.

 

So why do I bring this up? well think about the other 42 cars for a second. Some of them were press cars, some were used to do crash testing, some were turned into test mules all before being ordered to be destroyed. and what do I mean destroyed? well the chassis and engine blocks with the pre-prod vins have to be destroyed, but it wasn't like they didn't go through all of GM and round up all the parts taken off those cars and used for other mules or stolen and used for employee personal vehicles. When I worked for vette dreams and used to do all the shows in the 1990's, every once in a while someone would have a "1983 corvette" part that supposedly came from one of the destroyed cars. The majority were fake but there were a couple of "real" pieces that were identified with origins (I remember a set of wheels with a particularly interesting story). The bigger problem is that many of that stuff is not really identifiable as 1983 so it can be lost to time. So 1983 corvette parts are out there...they are just extremely rare.

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When you use an apostrophe in a year, it goes before the numbers because it's taking place of "19", so in this case it's '83.. unless you're talking about the model year 8300 Corvette, in which case you would be correct that no parts exist for those yet.

 

You're quite bored aren't you?

 

I was going to add that too, except there is ONE 1983 Corvette. It's at the Corvette museum (if they managed to fish it out of that sink hole). So technically, there are parts for an '83 Vette. All of them just happen to be ON the '83 Vette.

 

Touche! Didn't know that but not surprised at all!!

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May I present: the Bristol Hercules. Displacing 38.7 LITRES, up to 2,500 horsepower, and probably the most complex reciprocating engine ever devised.

 

Big%20f

 

BTW, that diagram was drawn by hand, not CAD rendered...

 

I always thought old aircraft engines were cool, and this one is no exception. One of my favorites though was the Rolls Royce Merlin. The part that I thought was neat was (in the later years) the 4 stage supercharger.

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