930 timing - 21 degrees max???????

[Craig 930 RS]

Strangest thing......the most timing I can get per the method: Pinch vacuum advance/retard (both are parallel to each other so I do both) Rev to 4k/above so timing does not change 21 degrees is all - Steve Weiner, who is associated/employed with the initial build and longer answers my e-mails, said in the past said that 26 degrees is the setting for my car. But the most I can physically get is 21 degrees - at which point the distributor cannot physically move anymore. Odd, huh? Ideas? How did they get 26 degrees before?

[JoeMag]

what rotor do you have on your car? there are multiple ones that will fit. some have a longer end and will limit how much advance you can get.

[fredmeister]

When you say that the distributor does not move anymore, what do you mean, does it hit the end of the stop in the slotted hole where it bolts to the case?
If so, then you need to remove the ditributor and reindex it one tooth on the gear so that you can get more range of adjustment. Basically take the distributor out of the case and turn it slightly and stick it back down in so that it engages a different tooth on the timing gear. This will rotate the shaft and rotor so that you have more movement before hitting the end of the slot in the base of the distributor when you set timing.

[beepbeep]

Yeah, fredmeister is on the track here. You probably have shaft one tooth off.

[Craig 930 RS]

Sorry, wasn't clear - the slotted section of the dist. will not allow the dist. to move any further.

[JoeMag]

i also agree on the off a tooth. if you pull out and reput in, the rotor will move a lot as the gear tooth engages. mark where you start on #1 mark on distr and adj slot so when you put back on you'll know you moved it in right direction.

[Randy Blaylock]

Pinching is not the same as disconnecting and leaving open to atmosphere. Your reading may not be accurate. Could be your measuring device also.

Your recent $20K plus lesson would suggest to a thoughtful person that a different magnitude of importance be assigned relative to extremely accurate ignition timing values. Lacking the knowledge of simple rotor gear re-indexing (if that's the case) is telling of an ongoing deficit of comprehensive understanding of rudimentary elements, let alone the operating principles of boosted engines with mechanical ignition devices. Not to mention the appreciation of the risks associated with/consequences of settings even slightly out of a narrow range of tolerance. Given the risks, perhaps the adjustment or verification is best left to professionals, or parties that are germane, unless you enjoy russian roulette or want to disregard whatever warranty that may have been offered.

[Craig 930 RS]

My 930 used to be owned by Randy.
It received a complete $24,000 rebuild in 2004, I purchased it in 2005, and it received - as Randy publicly reveals - another $20,000 complete rebuild in early 2006.
--------------
*Distributor lines are disconnected and effectively capped (pinched via clamps) per the 2004 builder's recommendations.
Both vac and retard lines are disconnected from distributor so as to not create a possible imbalance of plate movement.

*Two different timing lights were used. Both show the same measurement.

*Reindexing, yes of course. I've done this as a matter of course on 3 other non-porsche rebuilds I have done. One engine had distributor gears so coarse that reindexing made the adjustment slot go the completely different direction - ie full bottom to full top.
Didn't want to reindex and have it not work - it is a fair bit of work to get to the twin plug distributor (IC removal, very very tight access)

*Timing on the 930 has never been altered by myself.
It remains where the 2006 builder set it.

Posting here to glean actual experiences is valuable to me.
It sounds as if reindexing is indeed a functional possibility.

Thanks Joe, Fred, and beep for the information!

[RarlyL8]

Let me translate for you Randy.
Craig, you don't know what the hell you're doin' so keep your fool hands off the motor.

Eloquence is not my strong suit.

[rs911t]

Craig,

FWIW, Steve had two things to say when I asked about setting timing for my stock 930 track car (which, btw, has been running for who knows how long with the boost retard hose connected):

(1) Set timing at 10 deg ± 2 deg ATDC with the vacuum control connected.

(2) Factory spec is vacuum retard connected and if its run without it being functional, you WILL destroy P/C's.

At no time did he address max retard under boost.

That said, my local mechanic's opinion was to leave the boost hose disconnected and set the timing at 22 degrees ...

[Craig 930 RS]

I'd certainly expect Randy's pointed post:

"Lacking the knowledge of simple rotor gear re-indexing (if that's the case) is telling of an ongoing deficit of comprehensive understanding of rudimentary elements, let alone the operating principles of boosted engines with mechanical ignition devices."
Yowch.

would read diferently now if he read my prior post:
*Distributor lines are disconnected and effectively capped (pinched via clamps) per the 2004 builder's recommendations.
Both vac and retard lines are disconnected from distributor so as to not create a possible imbalance of plate movement.

*Two different timing lights were used. Both show the same measurement.

*Reindexing, yes of course. I've done this as a matter of course on 3 other non-porsche rebuilds I have done. One engine had distributor gears so coarse that reindexing made the adjustment slot go the completely different direction - ie full bottom to full top.
Didn't want to reindex and have it not work - it is a fair bit of work to get to the twin plug distributor (IC removal, very very tight access)

*Timing on the 930 has never been altered by myself.
It remains where the 2006 builder set it.

Posting here to glean actual experiences is valuable to me.
It sounds as if reindexing is indeed a functional possibility.

--------------------------

Making rash assumptions via couched and wordy remarks that imply I f'd up when I didn't.......come on.

[Ken911]

aw he is just pissed becuase you blew up his24k rebuild

[mb911]

reindex ithe dizzy and you will be all set.

also remeber guys that allot of times people are on the forum to learn.. I try to pick up something everyday. I don't take it at "word" but try to take something away. I for one am the person that does everything myself, weather it be rebuilding an engine or setting the VE's on my megsquirt. sometimes however you need that little bit of insight.. I do believe though that if you don't understand learn about it as much as you can before touching it..

[Randy Blaylock]

Sure, a person can learn something on these forums, at times on the order of an epiphany of sorts no less. I regularly browse this and dozens of other forums in an ongoing search for knowlege, much more than it would seem from my limited posts. I just tend to refrain from chiming in unless I feel that what I have to say has some basis in my own personal validated experience. I do appreciate however that there is a lot of traffic in basic conceptualizing, I just usually don't have the time to participate here and would rather do my testing in real life in the shop and at the track.

Having said that, in my opinion there is far too much opinion based on anecdote given as fact, particularly on this forum for some reason. A typical question is followed by a response endorsing a method or product with no rationale beyond the fact that the person making the endorsement uses that particular method or product, therefore it's the best. Of course that must be the case, because otherwise I made a bad decision. It's a self- supporting argument, and by definition has little to no real value.

How does this translate, and why did I respond the way I did?

Early 930 engines don't have any engine management electronics that act as a buffer for conditions that can instantly cause terminal damage. They don't tolerate experimentation with fueling and ignition. I think many people fail, and continue to fail to appreciate just how quickly things can go very bad, from seemingly innocent actions, and then suddenly you have a pile of junk and no one to blame but yourself.

Posting queries on a forum about subjects like ignition timing, when someone is looking for suggestions beyond the factory specifications for ordinary stock builds, need to include a comprehensive list of data points before any real judgements can be made. Especially for boosted air cooled engines with no electronic management systems that will step in to prevent excessive settings. Things beyond the usual build specs, in particular the cam profile type, lift/duration/LSA, and the cam timing setting, which all determine but only in part when the peak cylinder pressures will be present. Other things play into this; the intake design, the turbo map, fueling system configuration and ignition system type also play critical roles. The only real way to know what the timing value should be is to run the engine on a dyno, preferably an engine dyno with full instrumentation including an EGT monitor, begin with conservative settings, and sneak up on the optimum setting which should present itself as peak torque with proper EGTs and AFRs.

If a person doesn't have access to this equipment, the budget to support the testing, or possibly the intelllectual capacity or motivation to build the intellectual capacity then my recommendation of leaving things to the professionals only makes sense.

So from a practical perspective, in reality there is nothing to be gained from doing a survey about timing settings, except possibly just knowing you're in the ballpark and NOT using that range to experiment with. On the other hand, there is a lot to lose if a person chooses to assume that a committee style consensus validates a range of timing values.

The same can be said of many subjects, although the risks are far less when choosing a torsion bar size or tire size, to the point where it's probably O.K. to proceed with some information gathering and part selection, since worst case you simply won't care for the outcome, rather than taking a $20K (typical 930 rebuild) hit in the wallet.

Finally, I don't care for the personality conflicts that add nothing to the discussion, that usually have a basis in some emotional response, and that don't account for both sides of a story. It's not relevant and adds nothing to the discussion.

[briankeithsmith]

Well said Randy!

[mb911]

I agree with your statements I guess It may have just been to in your face to craig IMHO but maybe in hind sight really just a good suggestion

[Craig 930 RS]

A good point, Randy. I agree that often general internet advice can too easily become an action that is too readily taken into functional practice. You give good ~general~ advice.

I make it a point to consistently not translate generally unknown advice into direct action. If you look at my 930 rebuild thread, I took some action based upon advice and evident statements I received; received from some well known parties. Some directly involved. It was an unplanned, sudden, expensive and stressful undertaking. And one fraught with surprises at every turn that mystified or prompted some pointed and direct advice from those involved.

However, one must read this post again - and every one of my other timing posts (two total) - to clearly realize that I did not at any time ask "what should I set my timing to". Additionally, this post has nothing to do with queries regarding actual timing settings. I've asked what others had set their twin plug timing to, and this one simply asks a general question about distributor placement within the adjustment slot - and what might have others done or have experienced regarding this.

I received here - and usually receive in other posts what I consider polite, generally informative responses. And for that I thank the respondents. It's what makes this whole community of enthusiasts work together and brings a sense of camaraderie to our ownership of Porsches and especially these tricky devils called 930s.

Like I've said here - as well as to Randy in the recent & distant past - the recommendation was 26 degrees. I plan to stick with that.
I've gotten but 21/22 degrees with the distributor at the end of the slot/stop, and posting here regarding this is a simple inquisition and does no harm whatsoever. Leave it at that and lets move on....

[Jeff Alton]

I don't know what to set your timing at and am not sure how you should go about getting the 26 degrees you are looking for. That said, your first post with the comments about Steve may have set the tone for some of the other replies. Maybe I am wrong (happens all the time for me ) but it appears as though there is a "shot" in there. Or maybe not..... re-read it..........

Just the way it came across when I first read it.

Cheers

[TurboBert]

I haven't read through this carefully, but I too had a similar problem with my 79 930. If you have a US car perhaps it may be a similar issue.

No Throttle Body Vacuum at Idle

[briankeithsmith]

I agree with catca, you sort of took a cheap shot with Steve.

Remember, Do Unto Others As You Would Have Them Do Unto You - Steve begged, pleaded, and asked you to call him collect a few months ago on a Rennlist thread, and you refused to call, now you wonder why he won't answer your emails/phone calls?

And if your question was truly to ask what others are running for timing, what does that have to do with Steve, or any other mechanic?

Do Unto Others....