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Running top-entry dizzy cap on Sprite

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drooartz

drooartz

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Any reason I can't run the top-entry cap on my Sprite (with a 25D dizzy)?

My reason is that I'm currently running solid core wires as necessary for the screw-in side entry cap. I think those are what are messing with my timing light. Too much interference I think. (Light works just fine on the B with the same distributor but slip on wires.)

I'd like to try resistor wires, but need the plug-in style cap for that to work. Thoughts?
 
I use a top entry cap on my car.
 
Thanks, Trevor. I figured it would work but wanted to make sure there was enough space.
 
Will I need to switch to a different coil to? My current one uses a screw-in connector. I assume I'll need a push-on type. Moss does list two different types.
 
Another consideration is the combined resistance of the plugs and wires.
 
Trevor Jessie said:
Another consideration is the combined resistance of the plugs and wires.
Click to expand...
Now we're officially outside of my area of knowledge.
grin.gif


I'm currently running points, standard coil, solid copper wire on a side-entry cap, and non-resistor plugs (NGK). I just want my timing light to work...
 
Maybe the #2 solid core wire is interfering with the signal ? Does the TL act stupid on each wire ? ( obviously, only #'s 1 and 4 will be at the mark for timing, but 2 and 3 will also flash at the respective times)I can't imagine why a light wouldn't work with what you have.
 
I'll have to check that once I've got the car back over here next week.
 
You remember in another thread on this subject I said all my vehicles us solid core wires?
Timing light works just fine.
The one thing I can imagine on solids showing more apparent advance than resistor wires is it's not more advance. The resistor wires have less advance, and what gets to the plugs doesn't care, as long as you adjust timing for solid or resistor.
Think about it.
Engine spinning, sending a spark, if it's going down a resistor lead, the electrons are.....resisted.
Slower arrival.

Makes No Difference.

If your spark is dancing all over, I would suspect something else.
46 years of solid core wires and never a problem, cannot believe suddenly was have a problem with them?
 
It's not the spark that is the problem, it's the timing gun itself (has RPM gauge, and that goes wild too). Works just fine on the MGB, just not on the Sprite.

This is the second gun I've tried, with the same results.
 
The resistor woires will help if you have "noise" in speakers

The side entry is necessary on right hand drive models because #2 plug wire would interfere with the steering colum.
You can order a top entry cap by useing the mini part #
Phil Top Entry
 
If you go to advance distributor, you can pick up a top entry cap with BRASS connectors, as they should be. Jeff's preferred set up is that cap with a Bosch right angle plug wire (and coil wire set). Get one or two of his red rotor caps along with your order and Bob's yer uncle.
 
If I go down this route I'll give Jeff a call to get the right bits -- he redid the distributor on the Tunebug, and will get the one from the MGB when I get there.

It is handy that both cars run a Lucas 25D -- keeps the different spares to a minimum.
 
Last week I found a 25D in a Midget parked in the last row at the junk yard

Points, condenser are all there.
For $15.00 I took it home as a spare. I'll throw it in my boot as is, in case the Crane dies.

Phil
 
I've got my eyes out for a spare one of these days. B has Pertronix in it, so might be handy to have one ready to go.
 
When swopping out dizzys its important to get one that matches what you're taking out. There are numbers on the side and they have MEANING. They differ in the amount of vacuum advance, centrifugal advance and advance curve.


(https://www.teglerizer.com/mgstuff/advance_curves.htm).


Any spare will get you home, but should not be a long term solution
 
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