Spark timing question

[Kahuna]

Yes, Bubba
It is possible to find TDC using a dial indicator gauge. Mr. Ken Kloth loaned me a fixture he made to do just that. It consisted of a threaded bushing that screwed into the spark plug hole and then the hole in the bushing was slanted to the piston when installed correctly. The dial indicator had an extension. It worked real well when I used it on my stock 39 Ford coupe.
Jim

[Hoop]

Still wondering ...

If someone, like Bubba, sets the timing on a helmet or crab at 4BTDC and it's installed on an engine, will it fire at 4BTDC?

... with the engine running?

How about if the engine is turned over by hand. Will it still fire at 4BTDC?

Could you detect when the spark occurs?

If you had a pointer on the engine, could you mark a spot on the pulley where the spark occurred?

Would that be 4BTDC?

Could you then add other degree marks?

( ... what a dumb idea, huh.)

[Ol' Ron]

JS has the simplest method there is and is very accurate. The trick is to place a pointer in a continent location that won't move. A pointed stud in one of the timing cover bolt locations can do it. This method was originally made by Bruce Lancaster using a heavy tie wrap.

You can also check piston to head clearance by placing a thin piece of solder through the spark plug hole and squishing it. 37 Don came up with that one.

[flatjack9]

Originally Posted by Hoop

Still wondering ...

If someone, like Bubba, sets the timing on a helmet or crab at 4BTDC and it's installed on an engine, will it fire at 4BTDC?

... with the engine running?

How about if the engine is turned over by hand. Will it still fire at 4BTDC?

Could you detect when the spark occurs?

If you had a pointer on the engine, could you mark a spot on the pulley where the spark occurred?

Would that be 4BTDC?

Could you then add other degree marks?

( ... what a dumb idea, huh.)

You could use a volt-ohmmeter across the points and when the points open, this is where the spark occurs. Mark the pulley at that point. And yes if you set the distributor at 4 deg, that is where the spark will occur. I do check any distributor I build on an engine I have set up for that purpose.

[BUBBAS IGNITION]

Originally Posted by Hoop

Still wondering ...

If someone, like Bubba, sets the timing on a helmet or crab at 4BTDC and it's installed on an engine, will it fire at 4BTDC? (close )

... with the engine running? (close )

How about if the engine is turned over by hand. Will it still fire at 4BTDC?
(close )

Could you detect when the spark occurs? (yes ! )

If you had a pointer on the engine, could you mark a spot on the pulley where the spark occurred? (yes )

Would that be 4BTDC? ( maybe ? )

Could you then add other degree marks? ( you could)

( ... what a dumb idea, huh.)

We have driven these flatheads without a timing mark for years with no timing mark. However i agree that we need to know where the timing is for best performance, especially on a modified engine. We spent a couple days on a dyno with our Bonneville engine and our magneto had way too much timing in it, once we backed it off to 24 degrees , small changes up or down made very little difference in the power etc....

[Hoop]

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I have a confession to make.

That's not my "dumb idea." That's the design that Ford created, patented, invested millions in and built into millions of cars.

What is (close )? Seems like it worked for the Ford factories.

Anyhow ... what about "steamgas's" original question? How does he set his initial timing? Remember. even Bubba only gets (close )

What's the procedure for a guy who just wants to set his timing ... not go racing ... and would be satisfied with (close )? He doesn't care about TDC ... "dear Mr hoop this is the exact question i am asking"

Obviously the Ford factory was all screwed up with their idea. What do we tell ol'"steamgas?"

[Ed Pitts]

Use your Prince Albert can to set the points and drive it...................
Ed

[BUBBAS IGNITION]

Originally Posted by steamgas

i know this question has been asked before but i need to know where to go to get the information i need. my rebuilt engine runs good but i need to now set the spark timing. i know it has an adjustment on the side of the distributor but before i do anything i need to know what i am about to do. can someone please direct me to the information i need? this is a 1935 ford Flathead engine with the distributor on the front of the engine

Heres the most direct answer i can think of.

They didnt adjust the timing when they built them, they set the distributor and installed them. They have been driven around the world with no adjustment at all. They did provide a slight adjustment using the slide bar but that is very limited and is usually need due to extreme point rubbing block wear etc. A rebuilder could add a timing marker as he rebuilt the engine but the novice would be able to do very little with it.
AND you said it was running very good.

Bubba logic thinks it takes a Chevrolet mentality to even want to change the timing....

[BUBBAS IGNITION]

Originally Posted by Hoop

I have a confession to make.

That's not my "dumb idea." That's the design that Ford created, patented, invested millions in and built into millions of cars.

What is (close )? Seems like it worked for the Ford factories.

Anyhow ... what about "steamgas's" original question? How does he set his initial timing? Remember. even Bubba only gets (close )

What's the procedure for a guy who just wants to set his timing ... not go racing ... and would be satisfied with (close )? He doesn't care about TDC ... "dear Mr hoop this is the exact question i am asking"

Obviously the Ford factory was all screwed up with their idea. What do we tell ol'"steamgas?"

See my reply to orginal poster....

[Hoop]

(Bubba and I are generally on the same page ... or at least maybe only a paragraph or two off.)

Early on, dealers simply exchanged distributors rather than do much with them. As service fees started to get more attractive to the shops, they bought KRW fixtures. Later came Sun type machines which would generate more profit. Nothing like flashing lights to BS the customer.

It's only my imagination (and a lot of tinkering) that suggests factory distributors, like Bubba says, were set up and slapped on the engines on the assembly line. Some fast work with a feeler gauge then onto a gig like the slotted plates we see today. Hook up a light and slide the side adjuster until you get an indication of point break. Do a couple hundred a day and seeing the index mark line up at the same spot over and over ... you speed up and make more money since you're getting paid "piece work."

However, "steamgas" is up in the Shenandoah Valley at the foot of the Appalachians. Pretend that one of the dread mountain monsters from West Va. is on the prowl and he doesn't have time to waste. We still haven't help him set his timing ... speaking of which the time is running out (I'm from WV and know about the monsters that lurk there. Mothman, Yahoo, Yow ... plus a couple gals that will scare the wits out of you.)

So ... what do we know about distributors that does not require "steamgas" to remove a cylinder head or stick different objects in as bump stops.

If factory distributors were set up in a simple manner, what do we use to get this guy going, outrunning Big Foot?

[philipswanson]

Originally Posted by BUBBAS IGNITION

I had a customer tell me he put a dial indiactor on piston thru spark plug hole. I think he may have been on a valve , what do you think...


Just remember " the older we get, the faster we wuz""

It was me but I am not a customer. Spent $28 on a total rebuild which included a new condensor and point set.

[russcc]

This may work on the flatmotor. Tecumseh uses a special dial indicator that has a small right angle arm attached to the plunger that reaches from the spark plug hole over to the piston to measure TDC.

[AnthonyG]

Kahuna, I liked the indicator fixture for indicating TDC attaching to the spark plug hole with a slide rod going to piston top. Sounded like an easy accurate tool. I think I know how to make but a drawing would help. Can u or the guy who u got it from do a drawing & post?
Thx