engine and drivetrain 32/36 with 292 and 10:1

[zinz]

Here's some good reading on ignition timing for side drafts

http://www.bmw2002faq.com/topic/67587-ignition-timing-methodology/

http://www.bmw2002faq.com/topic/141041-dcoe-advance-ignition/

My setting? I set mine at 33 degrees at 2000rpm. That's sounds like a lot of advance, but that's where my engine runs best. You have more compression than me, so you might not be able to run that much advance. I used to run timing on the ball at 2400rpm...yes, it ran okay, but the engine REALLY came alive when I cranked up the advance.

Get an advancing timing light and experiment with your setup. Just be mindful of detonation.

Ed Z

[sczapiga]

On 2/23/2015 at 11:52 AM, zinz said:

By the way... my car has IE's 292 and had a 32/36 when I bought it.  I run Solex 40DDHs now and would NEVER go back to the 32/36.  I get better mileage with sidedrafts than I did with the 32/36... If I don't get 25mpg or better on the highway, I know something is amiss. I adjusted my advance curve a bit last week (using the 123Ignition distributer) and got 21.7mpg during 4 days of stop&go commute traffic.  (believe me...I'm not babying it either).

 

What seems to be the trouble with your setup? Give the details right up front, so as best to help out... Matched carbs? Jetting? Ignition setup, timing, etc...

 

Hope we can figure something out for you... Sidedrafts can be a challenge, but well worth the wait.

 

Ed

Hi Ed, 

I’d love to chat setups with you. I just had a full valve job with a ie 292 installed while it was open. I’m running a 32:36 synced and a 123 dizzy. It sounds like your on a similar setup, or, was as of 2015:) I just sent my dizzy to 123US in Ohio for the upgraded shaft and a cleanup from a bunch of oil. My car feels really “off” with the old original dizzy right now. Once I get the 123 back I’d like to dive into tuning the curves and jetting. 

[zinz]

I’ve dialed back some of that advance since then, but still run quite a bit of advance (maybe more than others).

 

I want to make clear, the engine in my ‘71 has flat top pistons. Those with different internals should only begin adding timing advance while continually watching for signs of detonation. For example, the engine in my ‘67 has piano tops and lots of other work. The advance curve for that engine is markedly different. 
 

Ed Z