69 L71 will not fire off

[Richard M.]

Re: 69 L71 will not fire off

Nice work Lawrence......I'm glad you got it all fixed it up.

And it makes me feel pretty good to be also thanked in the same sentence as Duke. He is, and always will be, one of the people here on my Hero-List. Thanks to him I've learned so much too.

Happy Holidays,
Rich

[Duke W.]

Re: 69 L71 will not fire off

Thanks for the compliments, guys. Regard the L-71 spark advance map, the centrifugal is fairly aggressive - 30 @ 3800 compared to L-72 (30 @ 5000), but the initial timing recommendation is only 4 degrees, which places total WOT advance below the optimum range of 36-40. So the first thing to do is advance initial to about 8 degrees. The actual compression ratio is what determines how aggressive the spark advance map cam be. Also converting from ported to full time vacuum advance is also a good idea. On L-71 it requires replacing the OE 15" 201 15 VAC with a 12" B-26 to pass the Two-Inch Rule assuming it has an OE equivalent cam.

[Lawrence S.]

Re: 69 L71 will not fire off

My initial timing is set at 8 degrees, the VAC is the 12" B-26. I don't know what the centrifugal is yet, and I need to change the vacuum from ported to full time.
I have been driving the car lately, and it drives great, and is a lot of fun to wind up! When the rpms reach around 4,000 the fun begins!
Thanks again,

Lawrence

[Duke W.]

Re: 69 L71 will not fire off

OE max centrifugal is 30 @ 3800. Depending on what the actual CR is you may or may not be able to make it more aggressive. A quick and easy way to convert to full time vacuum advance is remove the choke vacuum break hose and fab a new harness with a tee to provide a signal line to the VAC. The 12" B26 is the correct VAC for full time advance on L-71. Once the conversion is made go through the idle speed-mixture adjustment procedure and select an idle speed that produces at least 14" vacuum. The change can be made permanent and invisible by removing the carb, plugging the current VAC vacuum signal pickup and drilling a new hole to move it to above the throttle plate.