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Dr Evil
Hey all,
My ride is sounding like it wants to start, but I need to know some info that I don't have in my book.
Things to check:
-Where should I statically time it?
-What order do the plug wires go on the dizzy?
-What direction does the rotor turn, CW or CCW?

I may have missed something, but I know I have spark and that I have been able to adjust the dizzy so that at least one cylinder was hindered upon ignition. I need to re check my wire4s fro sure, but I am looking for some difinitve info.

Thanks drunk.gif
Dr Evil
More questions:

Do I need the braided ignition wires?
jtf914
- I don't use braided ignition wires, and mine has run great for the last few years.

- The firing order is 1-6-2-4-3-5, so this is the plug wire order around the distributor cap.

- Pretty sure the distributor rotation is CW, maybe some one else will confirm

When I reinstalled my distributor, I started with everything at TDC, so I turned the engine to TDC for #1. The flywheel passes TDC twice during one rotation of the distributor, once for #1 and again for #4. Setting the engine at TDC for #4 and then installing the distributor pointing to #1 will definitely cause problems.

TDC is the Z1 mark on the flywheel (and I believe it is marked on the pulley's if you are using those for your reference). There should be a mark on the distributor housing where rotor is pointing to cylinder 1. I lined the rotor up with that mark and reinstalled the distributor, tightened things down, started the engine and set the timing.

Let me know if you need pics of anything.

-Justin
Porsche Rescue
Justin pretty much said it all and he is correct that the distributor rotates clockwise.
DonTraver
Good Morning Mike. Some pretty good descriptions to help you here. One more, for static timing.

When the flywheel mark Z1 is lined up with the split on the case, the rotor of the distributor should be pointing towards the middle of the altenator clamping strap.

Once I have the distributor installed, I turn on the ignition and using a remote starter, start cranking and moving the distributor until she fires, then the timing light.

This discription is actually in the factory 6 supplement manual. Hope it helps, say Hi to Noel.

Later, Don
Dr Evil
Thanks for the info. I needed all of the basics so I could make sure I was not missing something.
-I did put the plug wires on the dizzy corectly (check)
-I have been setting the dizzy at either 1 or 180 out (more than one time so it was right once, check)

It could be that I was working on it for several hours until about 10pm. I'll see if fresh eyes this afternoon shows me anything that I might have missed.

I know that #1 wire is going to the right plug.....but I can't vouch for the others wink.gif


What do I set the timing at once it starts?
Dr Evil
Hey Don,
My notch on the dizzy for where #1 is is not quite in that spot. I will try it. It seems like that position would cause the timing to be ATDC, is that right?

I told Noel you said, "Hi." biggrin.gif
Dr Evil
I just realized something else, I have worked on many /4s and set the timing in my sleep with my eyes closed. But a 4 cyl = 90 degrees per cylinder, 6 cyl = 60 degrees per cylinder. In other words I may be moving the dizzy less subtly than I should.


Answers to come soon.....I hope.
smdubovsky
Im not used to a 2.7, but you'll need 5-10deg btdc @ idle and 35-40deg @ speed for a single plug. The 911 factory workshop manuals (you have those right? If you don't, send me an email;) describe the 2.7 advance curve. What year / spec motor do you have?

Here is probably the closest one (note the axes are for DISTRIBUTOR - double both for the crank advance and speed)
Click to view attachment

So, if you started @ 5-10deg at the crank, it will give right on 30 deg advance = 35-40deg total at >6000rpm.

SMD
smdubovsky
Mike,
You say the notch for the dizzy isnt exactly in the sopt. You mean the notch under the cap that the rotor should point to when #1 is at TDC compression stroke? If so, then thats right. Its not exactly lined up. If you put the dizzy in one tooth off either direction is is much further in error. It made me a little nervios not getting it centered either, but the timing light confirms it is correct. Again, I've never done it on a 2.7 - just my 3.0SC and also w/ a 3.6 twin dizzy - they had the same problem.

SMD
Porsche Rescue
To complicate matters further (once you get it to run), I had trouble with idle speed using a stock 2.7 CIS distributor and carbs without connecting the vacuum diaphragm. The stock idle setting with the vacuum retard on a CIS is about 5 degrees ATDC. When I set the timing where it had proper full advance at 6000 I was unable to get the idle much below 2000 rpm with carb speed screws fully backed off.

I have since changed to a '73 E distributor and the car performs much better, but my idle is still too fast. I may need to connect the vacuum retard. Still messing with the carb adjustment.
Dr Evil
Jim,
No carbs here. I can't afford the fuel economy and the price of admission wink.gif I hope it works better all OEM.

Salazar, thanks. It is gonna take some time to digest that data.
Porsche Rescue
Good decision. I can't believe the poor mpg (10-12) with my carbed 2.7. It may be jetted too rich but it runs very well. Since I only use it for DE/AX I can live with it. If it were a street car some changes would be in order.
jtf914
I had the same issues with a high idle, but I think the addition of a fuel pressure regulator dialed in at 3.5lbs helped a lot. I'd probably get better gas mileage if the sound of webers from 4000-6000 RPM's wasn't soo damn addictive driving.gif

Good Luck
rudedude
Are you using yhe marks on the flywheel or on the pulley? It seems to me when I switched to the 2.7 crank that the flywheel bolt pattern was different
than on my stock 2.0 crank. I painted marks on the flywheel and set timing per pmo about 5-6 degrees btdc as best for carbs.

good luck, it sure is fun when it runs well!
Porsche Rescue
I had the same issue. The marks on a 2.0 flywheel (required for use with a 901 tranny) are no longer correct when mated to a 2.7 crank.
As stated above, you have to use the pully marks and then mark the flywheel.
Dr Evil
Well today was educational, frustrating and down right angering.

I was finding the TDC of #1 by removing the plug and inserting a long piece of shrink tubing down into the cylinder. It was working better than trying to see the notches on the pully wheel which is a major PITA. I actually used a combo of the two as I could not match the notch up with the seam in the case.

So, I followed what Don said and put the notch and the rotor at the 1/2 way point of the fan strap. This was the best response that I got, but it still was not starting. It would just put a few times, like on one cylinder or something.

So now I am thinking it is not an ignition problem......or not JUST an ignition problem. I may have been later confirmed this suspicion.

Now I notice that the valve cover gasket seal is leaking from two lower bolts. Normally this is not such a big deal, pull and replace......but I am not everybody else. My oil cooler connection is in the way of the valve cover, so I now need to (once again) empty the oil out of my tank and engine so I can get the cover off......not a big deal as I was about to check the valve adjustment anyway. This also required removal of my header.

So I remove my header and to my dimay/surprise I find about a pint of gas sitting in them by way of it getting into my eye (yay).

So, by the looks of things I have/had a stuck injector or the fuel distributor was not working correctly. This engine is a fresh rebuild so the heads are very clean. This made it easy to decide which cylinder was the offending one as #4 was wet and dirty. I cranked my engine over a few times with the header off to see if I could get the fuel to pour out and of course it did not. Now it acts just fine.......but still wont start.

So, I need to at least check to make sure the valves are set as it feels to me that I am getting low compression and that this may be a reason for my no boom boom when I introduce the fuel.


Any ideas?



Here is some back ground:
-2.7 with SC cams fully rebuilt from the block up.
-I fully rebuilt the CIS with new seals and such.
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