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

[Artfrombama]

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)

I think you want to set total advance.
Due to manufacturing tolerances of the camshafts, intermediate drives, production (sloppy) distributors, dwell angle, rotor button etc., etc. no two distributors will index exactly the same in any two engines.

[VaccaRabite]

People are trying to help you because what you are asking is 1) unusual, 2) unhelpful, and 3) time consuming.

IF you are at TDC. And IF your timing gear is not 180 off...
Then your rotor will point to about Cyl 1. That's it. That's the starting position. No picture is going to get you more close then that. That's the rough in, and your car will be fine tuned with a timing light.

If your issue is you've done that and the car won't run, or is backfiring through the intake, that's an indication that something is wrong, and that will not be solved by what you are asking for.

Getting mad at us for trying to help you get there won't help you either.

Good luck.
Zach

[brant]

People are trying to help you because what you are asking is 1) unusual, 2) unhelpful, and 3) time consuming.

IF you are at TDC. And IF your timing gear is not 180 off...
Then your rotor will point to about Cyl 1. That's it. That's the starting position. No picture is going to get you more close then that. That's the rough in, and your car will be fine tuned with a timing light.

If your issue is you've done that and the car won't run, or is backfiring through the intake, that's an indication that something is wrong, and that will not be solved by what you are asking for.

Getting mad at us for trying to help you get there won't help you either.

Good luck.
Zach

(IMG:style_emoticons/default/agree.gif)
Any photo is impacted by camera angle
This idea of getting close to start is not really useful nor what so ever accurate
It’s oh so easy to run the throttle and light as one person
Do it with 2. Not hard either. But a picture will not improve the outcome

[Literati914]

I think you want to set total advance.
Due to manufacturing tolerances of the camshafts, intermediate drives, production (sloppy) distributors, dwell angle, rotor button etc., etc. no two distributors will index exactly the same in any two engines.

This statement is actually accurate I'd assume.
However I'm not trying to make my final setting off of a picture - as I said.
Take five cars and if they're set correctly the rotor will be in the same basic place every time, relative to the distributor body/plug tower. Simple.

[Literati914]

People are trying to help you because what you are asking is 1) unusual, 2) unhelpful, and 3) time consuming.

IF you are at TDC. And IF your timing gear is not 180 off...
Then your rotor will point to about Cyl 1. That's it. That's the starting position. No picture is going to get you more close then that. That's the rough in, and your car will be fine tuned with a timing light.

If your issue is you've done that and the car won't run, or is backfiring through the intake, that's an indication that something is wrong, and that will not be solved by what you are asking for.

Getting mad at us for trying to help you get there won't help you either.

Good luck.
Zach

Not mad at anyone Zach - I asked for a simple picture and got endless reasons not to bother or (as you just did AGAIN) and explanation of how timing is usually handled... so I'd say frustrated. I didn't ask for help in this situation, just a picture. I'd agree it may be "unusual", somewhat "time consuming" but it being "unhelpful" is just your opinion - fine. Thanks anyway.

[Literati914]

..At this point I'd rather just wrap this thread up. My curiosity as to where a rotor is normally aligned when the engine is timed has descended into another debate thread. Folks would rather argue about the merits than snap a couple pictures. Again, that's fine. I get it.

BTW - I've timed this particular engine more than once. The second time I did it.. I started at static "0" and then loosened the retaining bolt and "guesstimated" about where I thought the rotor was when I previously had it timed to 27. When I got the timing gun this time, I was very close and had it exactly where it needed to be in a matter of a short few seconds. My helper said .. "wow, it didn't take long at all this time!" (he'd struggled to hold the 3500 the first try).

Maybe I'll come back to this thread after I get it there again, and post a picture or two that may help others who find merit in the idea.

Thanks.

[emerygt350]

Something I would be interested in is where it sits at 900. I know tachs are off and weights can kick in early, etc. but I find my car is around 8-9 when it is around 28-29 all in. I always check both but it has never surprised me. If I move the 900 rpm timing a degree, the 3500 moves exactly the same amount.

[ClayPerrine]

As a starting point.. time it to 8 degrees BTDC at idle (900 RPM). It will start and run fine like that.

Then once you have the sticky throttle fixed, you can set it at 27 degrees at 3500 RPM to make it exactly right.

[Literati914]

As a starting point.. time it to 8 degrees BTDC at idle (900 RPM). It will start and run fine like that.

Then once you have the sticky throttle fixed, you can set it at 27 degrees at 3500 RPM to make it exactly right.

(IMG:style_emoticons/default/smile.gif) I have absolutely no problem getting the car started. Timing it to 27 is ONLY kinda inconvenient, I can and have done that too. The pic request was just as a convenience thing, a visual tool - based on the experience with the lucky guess I'd made last time. It's all good, thanks for everyone's help and suggestions.

[fixer34]

..At this point I'd rather just wrap this thread up. My curiosity as to where a rotor is normally aligned when the engine is timed has descended into another debate thread. Folks would rather argue about the merits than snap a couple pictures. Again, that's fine. I get it.

BTW - I've timed this particular engine more than once. The second time I did it.. I started at static "0" and then loosened the retaining bolt and "guesstimated" about where I thought the rotor was when I previously had it timed to 27. When I got the timing gun this time, I was very close and had it exactly where it needed to be in a matter of a short few seconds. My helper said .. "wow, it didn't take long at all this time!" (he'd struggled to hold the 3500 the first try).

Maybe I'll come back to this thread after I get it there again, and post a picture or two that may help others who find merit in the idea.

Thanks.

Yes, please post a picture to show us what you wanted so we can understand the request. I would have been happy to send a picture of my -6, but I doubt that would have helped.

[JamesM]

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

The majority i see are off in some way. You are lucky if its only off one tooth. I have seen them so far off as to have to re-index the plug wires.

[fixer34]

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

The majority i see are off in some way. You are lucky if its only off one tooth. I have seen them so far off as to have to re-index the plug wires.

Actually it doesn't really matter how the gear is indexed as related to the timing. (IMG:style_emoticons/default/stirthepot.gif)
The issue is with mechanical interference of the vacuum advance to the engine when installing it.
As long as the engine is at #1 TDC and the rotor lines up with the #1 plug wire location, you are good.
It does confuse the hell out of fellow 914 teeners though.

[Osnabruck914]

I feel for the OP. As the old saying goes - "He asked for the time and was told how to build a watch".

Osnabruck914

[ClayPerrine]

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

The majority i see are off in some way. You are lucky if its only off one tooth. I have seen them so far off as to have to re-index the plug wires.

Actually it doesn't really matter how the gear is indexed as related to the timing. (IMG:style_emoticons/default/stirthepot.gif)
The issue is with mechanical interference of the vacuum advance to the engine when installing it.
As long as the engine is at #1 TDC and the rotor lines up with the #1 plug wire location, you are good.
It does confuse the hell out of fellow 914 teeners though.

Actually, that is somewhat incorrect. Yes, the engine will run with the rotor pointed to any distributor tower. However, on a VW Type IV distributor, the #3 point cam lobe is retarded about 3 degrees from the other three. That is to drop the temperature on the hottest running cylinder. So you have to install the distributor drive correctly or the #3 cylinder will run hot.

This only applies to factory distributors. I don't know about aftermarket distributors.

[technicalninja]

Actually, that is somewhat incorrect. Yes, the engine will run with the rotor pointed to any distributor tower. However, on a VW Type IV distributor, the #3 point cam lobe is retarded about 3 degrees from the other three. That is to drop the temperature on the hottest running cylinder. So you have to install the distributor drive correctly or the #3 cylinder will run hot.

This only applies to factory distributors. I don't know about aftermarket distributors.

In 40+ years this is the FIRST time I've heard about a single cylinder being timed differently than others...

I was 100% in agreement with @fixer34 . Folks get so worked up on clocking when it really doesn't matter.

Clay's note is the kicker...

Ninja golden rule: " There are always exceptions".

With a stock distributor clocking is important on a T4!

Thanks Clay!

Little stuff like that make this the best forum...

This is EASY to test/verify. Time it up on #1 and then move inductive pickup to #3.

[Literati914]

.….However, on a VW Type IV distributor, the #3 point cam lobe is retarded about 3 degrees from the other three. That is to drop the temperature on the hottest running cylinder. So you have to install the distributor drive correctly or the #3 cylinder will run hot.

Ok that’s a significant issue then. The thing is that with the big ‘ol vac canister, there is really a pretty limited space in which it can be installed at all. I think my drive gear is fine but i don’t wanna run hot - so you guys tell me.

[Superhawk996]

.….However, on a VW Type IV distributor, the #3 point cam lobe is retarded about 3 degrees from the other three. That is to drop the temperature on the hottest running cylinder. So you have to install the distributor drive correctly or the #3 cylinder will run hot.

Ok that’s a significant issue then. The thing is that with the big ‘ol vac canister, there is really a pretty limited space in which it can be installed at all. I think my drive gear is fine but i don’t wanna run hot - so you guys tell me.

With all due respect - your drive gear doesn’t look correct. The dizzy drive has 12 teeth - each being 30 degrees of rotation. You are off by 1 tooth.

Compare to factory manual

[Literati914]

..
With all due respect - your drive gear doesn’t look correct. The dizzy drive has 12 teeth - each being 30 degrees of rotation. You are off by 1 tooth.

Compare to factory manual

I've seen that pic many times, but must confess I have no idea what 12degrees looks like and the black and white picture is less than clear. I'd gather from that pic however that - less angle would be more ideal ... but then I was able to get it to 27degrees. Now Clay's thrown a spanner in that sensibility (IMG:style_emoticons/default/headbang.gif)

I have the filter assembly etc. off while I chase a sticky throttle.. so now's a good time to correct this.

ps - this is how the engine builder installed the gear, no idea of his experience level.

[Superhawk996]

More photos of correctly installed dizzy drive

The 12 degrees is a bit confusing but it’s basically a reference of 12 degrees from engine centerline

Just focus on the fact that the two “c” shaped 1/2’s are not symmetric and focus on the orientation (smaller “c”) should be on the bottom





The more I look at yours I think the dizzy drive is 180 +/- a tooth off

[technicalninja]

(IMG:style_emoticons/default/agree.gif)

Be careful when you pull the drive out. There is a thrust washer on the bottom that will stay in the engine.

Use a light and verify it didn't move from its seat before sticking the drive back in.