Final Timing Question [I hope]

[Tinster]

Ok, here is exactly what I have.

1968 TR250 engine block

Everything below is new with less than 200 miles on them:

Jeff Schlemmer rebuilt dizzy to standard specs with
a petronix ignition inside it.

Standard coil ( I have a FlameThrower but not installed)

New Paul Rego throttle linkage shaft bushings

Plugs new and gapped gapped at .025"

Valves adjusted properly

New plug wires

Jeff Palya rebuilt carbs set to standard specs.
Rear carb running rich.

The photo shows my timing wheel and timing pistol.

IF I cap off BOTH carb pipes and I cap off both dizzy ears-
(eliminate the advance/retard system completely)

with the equipment and TR components I have installed....
How do I now proceed?

I am sorry to be so stone dead stupid on this one. It
escapes me.

Thanks,

dale

 

[Brosky]

Dale,

From what I see, you have a replacement damper. That is why there are no marks other than TDC (bigger slot) and the ATDC (thinner slot).

I have attached the only picture that I have of mine from when I was painting the engine way back that shows the two slots. All of the degree markings should be below the big slot from the drivers side view, with the ATDC slot above.

I have since installed degree wheel tape (a lot of work, don't go there!) and I don't have a picture of that yet. If someone can measure from TDC down to 4-8-12-16 on their damper, you could measure and mark yours accordingly and then time it more accurately from there.

I don't want to guess and give you the wrong info.

However, if you mark the slots so they are easy to see and use Ron's vacuum method you will get pretty close.

 

[Brosky]

Actually Dale, now that I look at yours and think of mine, that mark will probably represent 4* ATDC. So the distance from TDC to there will be the same in the other direction for each 4* increment, which is how the dampers are marked. If you download my image and blow it up, you will see the markings to the right of the white lines on the wheel.

Sorry, it was never intended for this detail. I would still like someone else to check the measurements.

 

[Guest]

Mark the same distance as the small line on the other side of the big line, block off your carb vacuums and proceed to time to the new mark, which should be about 4*BTDC, and go a bit farther if you want 8*BTDC. That would be centrifugal advance then, not vacuum advance. Both work, I like BTDC timing.

 

[Brosky]

OR, now that I see what type of light you have, you can leave it set for 12 and turn the distributor until you are on TDC, then lock it down. If you then turn the knob on the light to ZERO, you will see the "imaginary" mark move down below TDC to where 12 should be.

The car should be warmed up for this and as close to 850-950 RPM's as possible. You may have to readjust the idle and timing again after setting, as one affects the other, but it will be minor tweaking.

 

[Tinster]

Thanks Paul and Bill and everyone-

I'll ponder this for a few days.

Crypty's up on jacks right now having his
front end suspension gutted out.
Giving me DPO Pedro fits? Oh Yeah!!

Amos is sitting out on the terrace having a pina
colada and smiling while he looks at all his brand
front suspension parts that Crypty hasn't seen.

dale

 

[dklawson]

As was said above by Paul....

CONFIRM which of the two marks on the pulley line up with the pointer when you have #1 at TDC. After that, start the engine, warm it up, and set the timing light to your desired advance at idle. Loosen the dizzy clamp and turn the dizzy housing until the zero mark on the pulley lines up, then clamp the dizzy down.

Advance timing lights make this a pleasant experience. Lacking that you have to make the marks on the pulley as was mentioned above.

 

[RonMacPherson]

They've given you advice that I can not add to.

However, You state the distributor is rebuilt. Call the dizzy man and find out from him what advance cure is in it.

I'd like to hear his recommendations on total advance on his setup. Which version Pertronix do you have installed?

I have heard and read of the Pertronix's burning themselves out if the ignition is left on(and not running) for any time over 3 minutes.

If you do install a stronger output coil you should be able to open the plugs up to at least .030. make sure your rotor and cap are in great condition.

 

[71TR6]

Dale,
Here's an image showing my damper. Since I rebuilt the engine, I had the opportunity to take some paint and wipe it into the grooves of the markings to make them more visible (the ol peepers aren't what they used to be!). It clearly shows the ATDC & BTDC markings. Hope this helps!

RonW.

 

[Brosky]

OK, now I'm gonna have to find the pictures of the degree tape on mine. It's black and gold lettering and even my bad old eyes can see it.

 

[Brosky]

Dale,

Just out of curiosity, what did you use to adjust the metering jet in the rear carb? If you didn't use a tool like this, you may have inadvertently damaged the diaphragm.

The item is CAT1 on the right:

https://www.zeni.net/trf/TR6-250GC/33.php