Timing a /6, What the hell have I gotten myself into!? |
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Timing a /6, What the hell have I gotten myself into!? |
GrnEyedLdy |
Jun 10 2006, 01:48 PM
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#1
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FEAR ME! Group: Members Posts: 10 Joined: 2-December 05 From: Hershey, PA Member No.: 5,223 |
Sorry, Noel was still logged on....and I can't delete this for some reason
Ok, how? I now understand what Ed was saying about cutting an access hole in the fire wall. What a PITA. I would pull the vacc advance, plug it and rev to 6K. When I would adjust the dizzy it would run worse or better then worse (over the spectrum; bad-good-bad), but it would not move the timing visually. I have a couple of questions: 1. Do I need to adjust the timing to the RS cams that I had installed? 2. What is that value? 3. Anyone want to come down and do it for me? |
Series9 |
Jun 10 2006, 01:58 PM
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#2
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Lesbians taste like chicken. Group: Members Posts: 5,444 Joined: 22-August 04 From: DeLand, FL Member No.: 2,602 Region Association: South East States |
I just did this on Liz's car with a timing light and a mirror.
I left the vacuum attached to verify the advance at speed. I'm not sure whether or not your cams require something different. It's a pain, but you'll get it. |
brant |
Jun 10 2006, 03:06 PM
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#3
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914 Wizard Group: Members Posts: 11,824 Joined: 30-December 02 From: Colorado Member No.: 47 Region Association: Rocky Mountains |
I think many people mark their flywheel for TDC and use the flywheel port on the tranny case for timing?
I'm sure the captain will tell you that he has timed too many 914-6's to remember with a mirror or patience. me... I just sit comfortably in my driver seat and turn my head slightly to do my timing: Attached thumbnail(s) |
LvSteveH |
Jun 10 2006, 03:41 PM
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#4
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I put the Poor in Porsche Group: Members Posts: 1,080 Joined: 22-April 03 From: Las Vegas, Nevada Member No.: 600 |
I had to deal with this yesterday. Take the time to setup the flywheel with the appropriate marks for TDC, 120 degrees, 120 degrees. Then, no mirrors, and much more accurate.
The only hard part is getting it to perfect TDC, it's a little tough to get with a mirror and an odd angle. I also verified physically by using a TDC indicator. Not sure I like the tool, but it does work, even if you don't have any other marks to reference. |
pete-stevers |
Jun 10 2006, 03:49 PM
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#5
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saved from fire! Group: Members Posts: 2,645 Joined: 10-October 04 From: Abbotsford,BC, Canada Member No.: 2,914 Region Association: Pacific Northwest |
this is the final step to getting my car running this week.....finally
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Dr Evil |
Jun 10 2006, 10:27 PM
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#6
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Send me your transmission! Group: Members Posts: 23,034 Joined: 21-November 03 From: Loveland, OH 45140 Member No.: 1,372 Region Association: MidAtlantic Region |
I don't get it. You guys keep saying TDC, but I thought that I was trying to get it to 30-38 BTDC at 6k rpm. Am I completely off? It has been a loooong time since I hade to do any timing and then it was a /4 which is cake. Could someone enlighten me as to what I am supposed to do?
Latest update: I took it for a ride down the street, pulled it over and adjusted the timing, another block, same, worse, sounds like shit, power is unimpressive. I barely made it to the gas station (low gas may have been a factor in how it was running) put some gas in it, adjusted timing again and it ran OK (not spectacular at all), got home and got on the bike. I do know now that my allignment needs to be adjusted, it was very shaky. Should I be looking to adjust the valves now? Oil/filter? Thanks. |
LvSteveH |
Jun 11 2006, 02:11 AM
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#7
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I put the Poor in Porsche Group: Members Posts: 1,080 Joined: 22-April 03 From: Las Vegas, Nevada Member No.: 600 |
You have to establish "top dead center" for cylinder #1 in order to measure 30 degrees before top dead center at "X" RPM (usually full advance by 4000). A timing light with adjustable advance is a huge help here. If the engine is out of the car, you can find TDC on 1, and then measure out 30 degrees and add the mark, but it's tough in the car, so the adjustable light is great if you have to work off a TDC mark.
If you can find the mark on the crank pulley, and line it up as best you can with the fan housing notch, then verify that #1 is at the top of it's stroke, and the rotor is indeed pointed to plug #1, you can put a dab of whiteout on the flywheel in the notch at the top rear of the engine. You can then use that mark to time it using the aforementioned adjustable light (set the dial to 30 degrees, rev the engine to 3000+ rpm, and adjust as needed until the mark lines up with the case parting line. |
Dr Evil |
Jun 11 2006, 06:21 AM
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#8
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Send me your transmission! Group: Members Posts: 23,034 Joined: 21-November 03 From: Loveland, OH 45140 Member No.: 1,372 Region Association: MidAtlantic Region |
That was the piece that I was missing, the ADJUSTABLE timiing light. I was finding TDC with no problem (IMG:style_emoticons/default/biggrin.gif)....all the time (IMG:style_emoticons/default/dry.gif)
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sixnotfour |
Jun 11 2006, 09:08 AM
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#9
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914 Wizard Group: Members Posts: 10,682 Joined: 12-September 04 From: Life Elevated..planet UT. Member No.: 2,744 Region Association: Rocky Mountains |
RS cams and CIS dont work, do you mean SC cams?
Here is the timing spec 74-75 911-911S Attached image(s) |
smontanaro |
Jun 11 2006, 01:55 PM
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#10
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Senior Member Group: Members Posts: 1,190 Joined: 3-June 05 From: Evanston, IL Member No.: 4,197 Region Association: Upper MidWest |
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LvSteveH |
Jun 11 2006, 03:05 PM
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#11
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I put the Poor in Porsche Group: Members Posts: 1,080 Joined: 22-April 03 From: Las Vegas, Nevada Member No.: 600 |
I've got an Actron from Autozone, seems to be sturdy and work well. CP7519, about $70. Some of the nicer models are all digital and have lots of wiz bang features like being able to map the entire advance curve.
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Dr Evil |
Jun 12 2006, 02:19 PM
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#12
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Send me your transmission! Group: Members Posts: 23,034 Joined: 21-November 03 From: Loveland, OH 45140 Member No.: 1,372 Region Association: MidAtlantic Region |
RS cams and CIS dont work, do you mean SC cams? Here is the timing spec 74-75 911-911S Quite right, SC cams are what I have not RS. Thanks for postingthe timing specs. One of the guys that stopped by Matts house yesterday pointed out to me that my advance weights in the dizzy may be stuck. This was in response to me asking what I was missing about why my timing would not change with the vacuum hose disconnected no matter how much I revved it or changed the dizzy. Questions: Do I have weights in my dizzy with vacuum advance? Do I need to leave the vacuum hose attached and check to see if the advance is at full when it is supposed to be? Do I still need to get a light with adjustable advance? I can time it with the mirror and light, but I am not getting it to behave the way that I am expecting. I have forgotten more about this stuff then I can believe. (IMG:style_emoticons/default/dry.gif) |
ejm |
Jun 12 2006, 06:21 PM
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#13
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I can see the light at the end of the tunnel Group: Members Posts: 2,705 Joined: 3-February 03 From: Massachusetts Member No.: 224 Region Association: None |
QUOTE Questions: Do I have weights in my dizzy with vacuum advance? Do I need to leave the vacuum hose attached and check to see if the advance is at full when it is supposed to be? Weights are used in a distributor that has mechanical advance. Your distributor has both vacuum and centrifugal (mechanical) advance. To set the timing you disconnect the vacuum hose and set the timing to the spec for maximum centrifugal advance at the specified rpm. QUOTE Do I still need to get a light with adjustable advance? I've never needed one... |
lapuwali |
Jun 12 2006, 06:31 PM
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#14
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Not another one! Group: Benefactors Posts: 4,526 Joined: 1-March 04 From: San Mateo, CA Member No.: 1,743 |
You need a light with adjustable advance ONLY if you're timing to a different advance than stock (so the max advance mark is in the wrong place), OR, if you're only have a TDC mark (many 914/4s).
I thought you were doing crankfire on this engine... |
Dr Evil |
Jun 12 2006, 07:19 PM
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#15
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Send me your transmission! Group: Members Posts: 23,034 Joined: 21-November 03 From: Loveland, OH 45140 Member No.: 1,372 Region Association: MidAtlantic Region |
Ok, getting a little clearer. Thanks Gents.
I will eventually be doing crank fire, but I would like to get it working OE first before I start goofing with new things (IMG:style_emoticons/default/biggrin.gif) Plus, I need to figure out how to program it as well. (IMG:style_emoticons/default/rolleyes.gif) So to make sure I am getting this: -Provided I have a correct mark on the pully (I'll check), and provided that the weights are not stuck (again I will check), I will be looking for the specified amount of advance with the hose off at the specified RPM which should be accomplished via the dizzy weights, right? I just cant figure out why it runs so crappy, particularly on startup. Once warm I can coax it to idle, but I have little or no power at all and it sounds unhappy. |
sixnotfour |
Jun 12 2006, 08:05 PM
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#16
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914 Wizard Group: Members Posts: 10,682 Joined: 12-September 04 From: Life Elevated..planet UT. Member No.: 2,744 Region Association: Rocky Mountains |
at idle 900 RPM's hose attached 5 degerees after top dead center,
hose unhooked 38 max at 6000RPM's Is it lean or rich ? |
Dr Evil |
Jun 12 2006, 08:11 PM
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#17
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Send me your transmission! Group: Members Posts: 23,034 Joined: 21-November 03 From: Loveland, OH 45140 Member No.: 1,372 Region Association: MidAtlantic Region |
Lean or rich is a good question. I know that I have the cold start injector unhooked, and when I hooked it up it would backfire badly and still started hard. Also, when I am trying to start it I have to modulate the peddal vigorously no matter what when it is cold. this always leads to a rev and a die, and rev and a die, pop pop, etc.
Any ideas what to check now? I am guessing that it is most likely rich if it is wrong. |
lapuwali |
Jun 12 2006, 08:14 PM
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#18
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Not another one! Group: Benefactors Posts: 4,526 Joined: 1-March 04 From: San Mateo, CA Member No.: 1,743 |
Wild guess: dirty fuel and/or a fuel distributor in need of a rebuild (potentially from old dirty fuel). If so, it would be quite lean, which would make starting (esp. cold) very difficult. CIS really hates dirt.
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Dr Evil |
Jun 12 2006, 08:33 PM
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#19
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Send me your transmission! Group: Members Posts: 23,034 Joined: 21-November 03 From: Loveland, OH 45140 Member No.: 1,372 Region Association: MidAtlantic Region |
Here is some more info to help with the diagnosis:
I cleaned and sealed my tank and replaced fuel lines with SS. When I drove it down to the gas station, it did not run hot (like I would have guessed if it were lean). Maybe I need a new fuel filter? All gas is brand new. |
sixnotfour |
Jun 12 2006, 08:37 PM
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#20
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914 Wizard Group: Members Posts: 10,682 Joined: 12-September 04 From: Life Elevated..planet UT. Member No.: 2,744 Region Association: Rocky Mountains |
(IMG:style_emoticons/default/agree.gif)
try just makin richer or leaner with the mixture screw (1/4 turn is alot) never know might work. dont loose track of where you start if you turn the screw. you can do it while running. Here you go: http://forums.pelicanparts.com/showthread....ture+adjustment |
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