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Posted by: computers4kids Apr 15 2006, 03:58 PM

OK, I've got my vaccumm advance plugged and my timing light hooked up with the inductive lead on cylinder 1. I've read the pelican article on timing and it contradicts my Clymer shop manual. Pelican says you time a 1.8 at 800-900 rpm at 7.5BTDC, while 1.7 and 2.0s you time at 3500 rpm. My manual says its 3500 rpm for all 4s??? Which is it??

Secondly, I'm having a difficult time finding TDC. With the cap off I've rotated the engine until the rotor is pointing at the TDC notch on the distributor. The marks on my housing/pulley are not to be seen. Is it suppose to be near the one flatten blade on the fan? Yes, I rotated the engine 180 degrees as well.

Does this picture look like I've got the right idea for finding 7.5 BTDC?




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Posted by: Porsche Rescue Apr 15 2006, 04:11 PM

This might help


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Posted by: Bleyseng Apr 15 2006, 05:28 PM

for a 1.8l it should be 7.5 degrees

Posted by: Aaron Cox Apr 15 2006, 07:13 PM

you really need to be looking. the marks tend to be toward the rear of the fan (ie closest to the block) vs being on the pulley part. put a blanket down and lay on your trunklid to see.

it also helps to go get an adjustable timing light. it delays the spark X degrees so the only mark you need is the TDC. go get a thing of your wifes nail polish or a paint pen, find TDC and make it visible with aforementioned marking devices.

then take the timing light, set it to desired advance, and rotate dizzyy until you see the TDC mark.

Posted by: computers4kids Apr 15 2006, 08:16 PM

After just getting my 914 painted, I just couldn't get myself to lay on the hood! I did use a mirror though. I looked for the mark in both notches, on either side of the fan with no luck...probably rusted over.

Yes, I did buy a digital timing light that is adjustable so all I have to do is find TDC. There are no marks...I carefully spun the fan. I found the spot where it should be...it looked a little more shiny, and used it at least for today...it was pretty close. The 914 runs like a champ! I'll probably pull the valve covers and adjust the valves someday...and fix an oil leak...perhaps, watching for both valves I can better find TDC. I've never timed and engine with such a poor way of identifying its timing.

Thanks for your advice,

Posted by: Porsche Rescue Apr 15 2006, 10:41 PM

The diagram I posted is very accurate. Note the flat wide bar (shown at the 32 degree mark in the diagram) and count 4 1/2 fan blades to the right to find TDC.

Posted by: szuccaro Apr 15 2006, 11:28 PM

Just installed electronic ignition and had engine tuned to the following specs.. runs great!

• Adjust valves: 3 – 4 thousandths
• Installed compufire electronic ignition
• Adjust timing : 32 degrees Full Advance @ 3 thousandths +

Chrome Molly Steel Pushrods
Stroker Crank
78 Stroker; 96 Bore
Port matched manifolds
2 Liter heads with some port work

Posted by: Aaron Cox Apr 16 2006, 12:29 AM

a mallory unilite and a mallory hyfire CDI will blow your mind........

Posted by: Twystd1 Apr 16 2006, 02:47 AM

Chrome moly pushrods take ZERO lash last time I checked..

Twystd1

Posted by: DNHunt Apr 16 2006, 06:45 AM

Ditto on the chrome moly pushrods. Mine are set to 0 lash.

I added a little advance near and at WOT in the mid RPM range from the drivers seat. A few key strokes on the laptop and hit the burn button. Crankfire will blow your mind.

Dave

Posted by: Aaron Cox Apr 16 2006, 09:15 AM

Posted by: Joe Sharp Apr 16 2006, 09:23 AM

Yes but, Aaron how does it feel????
Sir, one zap, or two?
:PERMAGRIN: Joe