Adjustable timing?

[Whitetrashrocker]

I never do things the easy way. It runs in the family.

Have any of yoos guys ever made the coil adjustable? Instead of using an offset key, why not slide the coil.

I know you would have to make some timing marks, but simply find the radiant and Mark off a few degrees in each direction.

Sounds simple enough.

 

[mckutzy]

I think I saw an adjustable racing coil once, just as you describe, meant for a hopped up briggs flathead... Theory makes sense, why uproot the flywheel if you don't need to...

 

[Flyinhillbilly]

I've considered this too, even thought about a thumbscrew for on the fly adjustment. I'll never do it though.

 

[Bbqjoe]

I never do things the easy way. It runs in the family.

Have any of yoos guys ever made the coil adjustable? Instead of using an offset key, why not slide the coil.

I know you would have to make some timing marks, but simply find the radiant and Mark off a few degrees in each direction.

Sounds simple enough.

I think this would actually be a piece of cake, or pie, if you like.

 

[Kleyny]

How far do you think you would have to move the coil for say 2deg in timing?
Not a bad idea really.

 

[Bbqjoe]

How far do you think you would have to move the coil for say 2deg in timing?
Not a bad idea really.

I'd say about 2 degrees.

 

[mckutzy]

I reckon a bracket that has slots for the coil to travel in an arc, could be used to have an additional timing, kinda like this one but adjustable.

 

[Randy H]

How about this?

 

[Whitetrashrocker]

I reckon a bracket that has slots for the coil to travel in an arc, could be used to have an additional timing, kinda like this one but adjustable.

Looks like that's a drop bracket. Coil need to be moved in for the smaller flywheel.

---------- Post added at 08:12 AM ---------- Previous post was at 08:09 AM ----------

How about this?

That looks promising. Where did you find that? Perhaps I can fab one.

I was looking last night at the set up and thought about 2 plates kinda like that but in not sure the soil will have clearance on the one shown.

 

[Randy H]

https://www.vegascarts.com/11-degree-adjustable-timing-bracket-p/atb11.htm

 

[Whitetrashrocker]

How far do you think you would have to move the coil for say 2deg in timing?
Not a bad idea really.

I have an 8" flywheel so the math goes like this:

N°/360° x 2πr

Fill in our variables, n=2 and r=4

2/360 x 2π4

.005 x 37.69

This equates to .139 inches.
.140 is equal to 9/64.

So by moving the coil 9/64ths would be the equivalent to 2°. But this is only for an 8 inch flywheel.

 

[Randy H]

https://www.vegascarts.com/11-degree-adjustable-timing-bracket-p/atb11.htm

I gotta say though, I'm not to sure about those guys. I called to ask a question about a cam and they had no answer. The guy I talked to had no idea what I was talking about. Questioned why I would need that information and stated that no one there would know.

 

[Whitetrashrocker]

https://www.vegascarts.com/11-degree-adjustable-timing-bracket-p/atb11.htm

I gotta say though, I'm not to sure about those guys. I called to ask a question about a cam and they had no answer. The guy I talked to had no idea what I was talking about. Questioned why I would need that information and stated that no one there would know.

Sound like a typical parts warehouse.

 

[Flyinhillbilly]

I reckon a bracket that has slots for the coil to travel in an arc, could be used to have an additional timing, kinda like this one but adjustable.

I
Love the fact that this is an adjustable flywheel

 

[itsid]

I wonder if it's possible to not only have adjustable timing but rather variable timing based on rpms as well..

I mean the purely mechanical I doubt the intake creates enough of a vacuum to make that happen pneumatically.. but what if one would use a beefed up governor (heavier flyweights)
and install that in a way that it advances timing slightly at higher rpms... *shrugs*

just a thought, but I don't really see why that shouldn't be viable (well maybe not trivial ..likely overkill and not as reliable as a commercial (electronical) way...)
but just imagine you had that on your clone.. it'd be awesome

'sid

 

[Whitetrashrocker]

Why not. The use of vacuum advance on cars has been around for a while.

Just a whole bunch of hoopla for a lawn mower.

 

[Joe-405]

My raceseng flywheel and coil mount were adjustable fully................

 

[mckutzy]

I wonder if a small pneumatic cylinder coud be used in that fashion... Where could be the tapping point for the vacuum?..