2.7 advanced timing

[77carrerabt]

Can any one tell me if there is any upgrade done to the 2.7 911 S engine that would require the timing to be advanced (extremely). I.E. if the engine has been rebuilt with cams, or perhaps the distributor dwell angle has been altered or any number of things I have no clue about. The reason I am asking is because the timing mark when striking Z1 is showing extreme advance on the D timing mark. I figured it was off by a tooth so I pulled out the D and moved it back one tooth and the car would not start. I moved it back to the original position and the car started right up and runs seemingly well. What I have done in the mean time is to simply turn the D and try to get the timing mark as close to 5 degrees ATDC as possible but the D is turned as far to the right as it can go.
The engine was rebuilt but I do not know the details of the build. I believe it has some type of cams in it because it pulls very hard from about 3K up to and over 6K. ( I have been apprehensive about taking past 6K). It does have a small dead spot in second gear at about 2200 -2700 rpm but once in third gear it is a whole new animal!!!!! Thanks for any help and information.

[psalt]

Do you have a vacuum retard distributor and what is your high speed ignition timing ? The ATDC specs are all about meeting the HC emission test and are largely irrelevent for performance. I would try to identify which distributor you have by part number and focus on high speed timing with vacuum disconnected.

[RoninLB]

disconnect the vac retard line and plug it

set initial to 0 then set total timing to 35

this is for 8.5:1 pistons

[T77911S]

mine is too.
dont worry about it. if you run out of adjustment, remove the dist and put it back in one tooth opposite of the way you want to go. man, i had to think about this.
if you are trying to turn the dist CW, hold the rotor and lift the dist enough to get past the gears, turn the rotor AND dist CCW enough to drop it back in one tooth. now you can continue to turn the dist CW.
if you have doubts about doing it, line everything to TDC and just make sure the rotor is still point at (it will not be at the mark but close) to it when it is back in.

you cant turn the one without turning the other, as you have found out.
if the rotor is no where near the TDC mark on the dist when the pulley is at TDC, your plug wires may be off one. if it is 180 degrees off, turn the crank another 180 degrees for true TDC.

just make sure your advance is working properly and set it to spec if you are not sure. i thought spec was 0TDC though. with the vac retard connected, i set mine to 5-7 ATDC.

gotta go to work, i did not get to really check this over

[5:04]

What's your initial timing and what is it at 6k? If you're nervous to take it that high you're almost all in at 4-4.5k and can check there. My vacuum retard is disconnected so my initial is pretty high, but at 6.5 I'm almost conservative. I have a hot 2.7 as well with Solex Cams, Webers, and JE 9.5:1's. Also with that dangerous of an advance you should be able to feel/hear ping if it's out of whack.

[77carrerabt]

Originally Posted by 5:04

What's your initial timing and what is it at 6k? If you're nervous to take it that high you're almost all in at 4-4.5k and can check there. My vacuum retard is disconnected so my initial is pretty high, but at 6.5 I'm almost conservative. I have a hot 2.7 as well with Solex Cams, Webers, and JE 9.5:1's. Also with that dangerous of an advance you should be able to feel/hear ping if it's out of whack.

did not notice or hear any pinging. According to what it was set at originally, I have it retarded now. it runs well, no missing or back firiging. I guess I could try to advance it in small increments and see what happens.

[5:04]

You need to know what your timing is set to at 6k. If it's too advanced it could be dangerous, and being too retarded is bad for efficiency and it's wasted power. Do you know how to time your car? I think there are a couple of great tutorials on here.