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Hi Brian, Steve. (re: post #60).
There are very good engineering reasons for long bolts holding engines together. (Simply put, Long springs keep the load, short ones vary the load: The long studs act as long springs holding everything together while temperatures change and expansion and contraction occur.). Especially when an engine has "long" Alloy components and steel bolts, sealed by "hard" gasketing. So "what looks good" is sound Engineering practice.
But Brian's design is using O-rings, not "hard" gaskets, so the O-rings will have the compliance to compensate for "Joint movement". Additionally, with the same materials for block, bolt and cylinder head the expansion and contraction variation between bolt and parts is effectively zero. - Again, good Engineering here.
K2
 

Brian Rupnow

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I'm running out of "quick and easy" parts to build. Today I will attempt the swoopy looking gas tank mount and the tank itself, and then I get into the more technically challenging things like con rods and crankshafts. I'm building this engine in reverse---most times I recommend that people build the difficult engine parts first. If they can build the crankshaft, con rods, and valve train, then they can go on to do the easier large parts. Thank you to all who are following this build thread.---Brian
 

Brian Rupnow

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Holy Gas Tank Batmen!!!--There's a full days work in that gas tank and bracket, but I like it a lot.
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Brian Rupnow

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Not a lot of new fabricating today, as I had some automation design to do for an old customer. However, I did get my new points and condensers and had to try them to make sure they fit, and I managed to pick up some oilite bronze bushings for my camshafts and the two idler gears.
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dsage

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Hi Brian:
What vehicle do you ask for points from when you buy them. They must be getting scarce.
And where from - CTC?
Going to need two coils as well. Right?
 

Brian Rupnow

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The points are for a 1959 to 1972 Plymouth. I buy them from Partsource---and yes, they are "special order" items now. I think I can get by with one coil. Back in the day, a single coil ran 6 or even 8 cylinders.
 

Brian Rupnow

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Today was gear making day. Not terribly difficult but time consuming. Tomorrow I will add a bunch of set screws and get all of the gears meshing with one and other.
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dsage

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The points are for a 1959 to 1972 Plymouth. I buy them from Partsource---and yes, they are "special order" items now. I think I can get by with one coil. Back in the day, a single coil ran 6 or even 8 cylinders.

Thanks for the source of the points.
As for the coil issue. I was referring to the wiring. I guess it will be wasted spark then. Will that work with the cylinder angle / valve timing etc.
Looking good..
Thanks
 

awake

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Points for various engines are readily available on Amazon. I've used points for old Ford tractors; I've seen others use points for Tecumseh engines or similar.
 

ozzie46

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Brian I sent you a private message about when you first got your rotary table.

Ron
 

Brian Rupnow

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Yesterday the cam gears were completed and the engine was driven by an electric motor to wear in the gears for a perfect mesh. The camshaft support blocks were drilled for bushings and the cam shafts installed. The ignition cams were made and installed. The ignition points were installed, but there was a fitment problem and I am going to have to redrill two holes and move them around a little bit.
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dsage

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It will not be "wasted spark" ignition. The cams are running off the camshafts.

Hmmm. The arrangement should be interesting. Maybe I'm missing something. Two sets of points, driving one coil, with two spark plug cables from the same coil. How will only one cylinder fire at a time?

No need to elaborate. I'll stay tuned.
 

Brian Rupnow

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dsage--I may have to think that out a bit more. With only one coil and two sparkplug leads required, and no distributor to designate which plug is being fired, I may well have to go with two coils. Thanks for bringing it to my attention.---Brian
 

Gordon

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If I remember correctly you built a twin cylinder before and you used a dual coil with two spark plug cables. Lawn mower coil if I remember correctly.
 

Brian Rupnow

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No, actually it was a twin cylinder snowmobile set-up, and it worked really well. Since the ignition is really a separate thing from the machined engine components, I haven't given it a lot of thought. If I were to incorporate a distributor that would direct which sparkplug the spark was going to, I could get away with one coil. This summer my main goal is to machine and assembly all of the engine components, then worry about the ignition after the engine is built. I may be getting the horse ahead of the cart here. I do have an extra 12 volt coil kicking around, and I do know I can make this system work with two sets of points and two coils, with no distributor required.
 

Brian Rupnow

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I keep redesigning and refining this engine as I build it. I'm almost at the point where I need to start building finned cylinder heads.---and I'm thinking how great they would look made from brass. Aluminum works, and works very well, but brass is sooooo pretty!!! I need a piece of brass flat bar 2" x 3/4" x 4" long to make two cylinder heads. On Monday I will call my metal suppliers to see what a piece of brass that size would cost me. I'm pretty sure that the last time I used it my 0.094" slitting saw blade (which I cut fins with) was dull as a hoe, so I'll probably need to replace it also. Tomorrow is scheduled to be a big backyard birthday party for my daughter and I (I just turned 76 and my daughter is turning 38) so a family party day will give me another day to think about this.
 
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