Pic Request : Rotor while engine is well timed (27deg BTDC) Options

[Literati914]

I'm hoping someone can snap a picture of the distributor with it's cap off - to show where the Rotor is pointing while the engine is actually timed to 27 degrees (the normal factory timing over all the 914 typeIV engines, I believe).

No adjustments would be needed on your end of course - BUT to make the picture usable it would require the photographer to rotate his/her engine to the initial timing "0" degree mark on the compression stroke with the engine off. (your car stays timed at 27 of course)

Why do I need this? - because I'd like to get the rotor in the ball-park before my assistant (w/ very limited experience) tries to maintain 3500rpm with my somewhat sticky throttle (to address soon).

So, may be kind of a hassle but I'd think it could also help others trying to time their engines for the first time too. We know what the rotor looks like at TDC, but there are no pictures available like what I'm asking for (I looked but couldn't find). I'd appreciate it if someone could help please!

ps - if posting the pic is an issue, I can provide my phone# so you can text it to me and I'll post it. LMK

[brant]

the problem is the gear under the distributor can often get moved 1 tooth.
making it look like 2 distributors are at different positions, when they are really both TDC

you have to pull a valve cover and verify TDC

[Literati914]

Maybe it's an anomaly but my dist. has a small notch at it's top/rim area, that the rotor lines up with when the engine is set at TDC/"0" for initial time setting (it certainly looks factory). I can use that to estimate. I hear ya, but it's not that hard.

Also, if your distr. does not have this notch, then a pic shot down from directly above with the cap on and a note of which wire goes to #1 cyl, would probably be just fine.

[brant]

put the motor on TDC number 1
verify with valves...
then pull the cap and make sure the rotor is pointing at plug wire #1

done.

[Literati914]

put the motor on TDC number 1
verify with valves...
then pull the cap and make sure the rotor is pointing at plug wire #1

done.

No not done.. the timing needs 27deg. BTDC. Brant I believe you are answering a question I did not ask. Thanks though.

[Jack Standz]

What Brandt said.

Make 1000% certain you have your fan marked exactly at TDC on the compression stroke for the #1 cylinder. For any time you try to time your motor.

Use this or a similar timing light to set timing at idle and fully advanced (3500+). The benefit is you do not need an assistant as you can increase engine speed yourself (turn throttle by hand) while watching the tachometer on the timing light. Added bonus is it's much more accurate than the tachometer in your 914. A "dial back" timing light is the way to go.

https://www.amazon.com/INNOVA-3568-Digital-...fYXRm&psc=1

Innova 3555

The Innova 3555 Advance Timing Light features a direct reading advance dial that adjusts from 0-60 degrees; enabling the user to check base timing and advance or retard timing. This timing light works with most ignition systems (conventional, electronic and computer controlled systems - domestic and import) with a patented skip circuitry to test up to 9,990 RPM.

[Jack Standz]

If you want to know what 27 degrees looks like, remember that the distributor rotor turns at half crankshaft revolutions. What does this mean? 27 degrees of the crankshaft will look like 13.5 degrees of the rotor (or half).

Take a 90 degree angle (like a carpenter's square). Bisect the angle. That gets you 45 degrees. Bisect it again, getting you 22.5 degrees. Bisect it again and you're at 11.25 degrees. Accounting for imprecision in all those bisections and that's close enough. Or use a protractor to see where the rotor will be approximately positioned at full advance. It's really not all that much.

But, really how does this help time a motor (other than visualization of rotor position at full advance - which might be useful)?

[Jack Standz]

Here's a 13.5 degrees angle. So compare it to your rotor position at TDC and this 13.5 degrees will be the difference at full advance.

https://grinebiter.com/image/angles/13.5-degree-angle.png

[Literati914]

@Jack Standz and @brant

Im confused as to why you guys are making the assumption that I do not know how to time the engine, or that i do not have an adjustable timing light. That is not what im asking for. Seriously, thanks.. but just read my request, it says nothing about how to find tdc, etc. (or 27d for that matter). It’s distracting tbh..and now I doubt anyone will step up because hey, i must be asking for something unreasonable, right?

Btw, it may be possible to do it solo as you describe - hold and pull the trigger on a timing light, while working the throttle by hand .. and also get the distributor where it needs to be, all while your arms are awkwardly stuffed into the engine compartment - but id rather not do it that way, an since i have willing help, why would i bother?

Anyone who has a descently running 914 /4 could shoot a couple pictures. I understand most won’t care to mess with rolling the car to find “0” on the fan which is fine. No worries. I just figured someone might be willing to volunteer before the thread got side tracked. Its all good though, I’m starting to expect as much tbh.

[Literati914]

..But, really how does this help time a motor (other than visualization of rotor position at full advance - which might be useful)?

Because remember when I wrote this? :
“..Why do I need this? - because I'd like to get the rotor in the ball-park before my assistant (w/ very limited experience) tries to maintain 3500rpm with my somewhat sticky throttle (to address soon…”

I’m obviously not trying to rely on the visual for my final setting..

[emerygt350]

I would send you one but I am away from my car for another few weeks and I run a couple degrees advanced, or at least I think I do. Variation in timing marks and all that.

I see what your doing and I think it's not a bad idea to start at a better place than TDC on assembly.

[fixer34]

I have a -6, so can't help with pictures, but even from the peanut gallery I'm trying to understand what you are trying to accomplish.

You want to set a 'start point' for the distributor timing, got that. However, you are obviously doing that when the car is NOT running. That start point is TDC on #1 with 0 deg advance. Generally there is a small line/notch on the distributor outer ring that the center line of the rotor should line up with. This all assumes you have the points correctly installed and the gap/dwell correct.
The points should be closed at that point. Put an ohm-meter across them (car turned OFF) to check. Now rotate the rotor (clockwise I think) just a very little bit, the points should open/ohm-meter shows open circuit.
THAT is now your starting point.

27 deg BTDC is full advance at 3500 RPM. There is no way I know of to set that statically. It has to be done with a timing light.

If you really want to have 'fun', try doing a factory -6 sometime. Leaning over 3 open Weber stacks to check the marks on the flywheel, engine at 6000 rpm, trying to dial in the distributor for 35 deg BTDC.

[Jack Standz]

..But, really how does this help time a motor (other than visualization of rotor position at full advance - which might be useful)?

Because remember when I wrote this? :
“..Why do I need this? - because I'd like to get the rotor in the ball-park before my assistant (w/ very limited experience) tries to maintain 3500rpm with my somewhat sticky throttle (to address soon…”

I’m obviously not trying to rely on the visual for my final setting..

Doug,

My apologies, I guess I didn't understand the question (still don't). (IMG:style_emoticons/default/smile.gif)

Best wishes with getting her set.

[Literati914]

I have a -6, so can't help with pictures, but even from the peanut gallery I'm trying to understand what you are trying to accomplish.

You want to set a 'start point' for the distributor timing, got that. However, you are obviously doing that when the car is NOT running. That start point is TDC on #1 with 0 deg advance. Generally there is a small line/notch on the distributor outer ring that the center line of the rotor should line up with. This all assumes you have the points correctly installed and the gap/dwell correct.
The points should be closed at that point. Put an ohm-meter across them (car turned OFF) to check. Now rotate the rotor (clockwise I think) just a very little bit, the points should open/ohm-meter shows open circuit.
THAT is now your starting point.

27 deg BTDC is full advance at 3500 RPM. There is no way I know of to set that statically. It has to be done with a timing light.

If you really want to have 'fun', try doing a factory -6 sometime. Leaning over 3 open Weber stacks to check the marks on the flywheel, engine at 6000 rpm, trying to dial in the distributor for 35 deg BTDC.

Oh my God, are you serious. I don’t need anything that you just wrote and I’ve already re-explained my intentions. Not to mention I even mentioned the notch that you spoke of. How hard is it to understand that the rotor will be pointing to a particular spot and that’s all I’m trying yo get a since off (IMG:style_emoticons/default/confused24.gif)

Please no more how-to comments if y’all don’t mind.

[sixnotfour]

static time,lock it,, twist rotor to make mechanical advance work where the rotor stops is max mach. advance...mark the housing ..

[Literati914]

static time,lock it,, twist rotor to make mechanical advance work where the rotor stops is max mach. advance...mark the housing ..done

Here we go, another explanation (IMG:style_emoticons/default/rolleyes.gif) Lock it.. then twist rotor??? Sorry that doesn’t even make since.

I know, why not just shoot a quick picture or two?

[sixnotfour]

static time,lock it,, twist rotor to make mechanical advance work where the rotor stops is max mach. advance...mark the housing ..done

Here we go, another explanation (IMG:style_emoticons/default/rolleyes.gif) Lock it.. then twist rotor??? Sorry that doesn’t even make since.

I know, why not just shoot a quick picture or two?

would give you an idea of the mechanical advance travel distance when at max advance..

Sorry I don't own any T-4s

[rjames]

I’ve read this thread three times and I still don’t understand it.
Based on an earlier post you made, I’ll go the other way and make the assumption that you do know how to time the engine and you do have a timing light, since that is what you implied. If you know how to set the static timing it, you’ll already be ‘in the ballpark’. How is a picture going to help you further? The process will be the same whether you have a picture of not.
(IMG:style_emoticons/default/confused24.gif)

[Literati914]

would give you an idea of the mechanical advance travel distance when at max advance..

Sorry I don't own any T-4s

Understood.

[Literati914]

name='rjames' date='Apr 21 2025, 11:14 PM' post='3202191']
.. How is a picture going to help you further? The process will be the same whether you have a picture of not.
(IMG:style_emoticons/default/confused24.gif)

Because as I’ve mentioned for the 3rd time now:
Why do I need this? - because I'd like to get the rotor in the ball-park before my assistant (w/ very limited experience) tries to maintain 3500rpm with my somewhat sticky throttle (to address soon)

getting it even closerrrrr to it’s final spot before starting the timing gun makes the 3500rpm hold a lot shorter which is helpful if you’ve got an inexperienced helper and a sticky throttle. That’s understandable, right?

Never imagined I’d get so much resistance to a simple picture or two (IMG:style_emoticons/default/confused24.gif)