Timing, Pertronix change over 3.0?

[Starcraft5834]

I've got 1987 3.0 GM 181, anyone know after electronic ignition change over if the timing has to be changed from 6 BTDC, to something else? I've read anywhere from 1 BTDC and up.

anyone else convert with a 3.0?, what you guys do? thanks much

 

[Benny67]

A spark is a spark. Doesn?t matter how it's created or how stronger it is than the old one. You probably have more room to play around with it than the conventional points but my .02$ is to leave it at what the specs for the motor call out for.

I just did both my 470's this weekend and set timing to factory settings plus 1 degree cause the motor seemed to be a bit more smoother than the recommended setting.

Hopefully these pertronix are reliable...I have heard good and bad about them.

 

[Starcraft5834]

thanks for feedback.. it fired right up, old points idle was about 700-800 rpm, with the pertronix/40K flame thrower it was running quicker about 1000-1200 at base idle.. it certainly caused it to run stronger with same fuel supply... gonna mess with it wed.

 

[Benny67]

Funny, mine was exactly the same way....just a bump of the key and it fired right up. With the points it would crank for a second or so. I also had to idle down a touch.

Good luck with them.

 

[thejeep007]

Did my'n when I bought it, always idled rough and found this video. Ordered correct rotor so we will see.

https://youtu.be/jxrhgUa11-M

 

[Starcraft5834]

no question, started much faster immediately. my boat's been sitting idle since end of July last year, did not get out again, covered it up, drained all the water out of block and manifold and it sat for nearly 10 months... so, bought the conversion kit, had friend help me, he's the head GM mechanic at local dealership, put in unit, had to dump some gas down the carb, fired it up, adjusted a bit... will finish adjustments wed this week. one bump of key and boom, with points would take several turns.. it's clearly running stronger with same fuel supply set up used for points.. idle adjustment mostly... looking forward to seeing how long this unit will stay working properly.... until now every year had to buy new points and mess with that, will keep the points in the boat just in case..

 

[Benny67]

Jeep,

Good link.

That video points out a few things to look at when you are doing the changeover.

My kit didnt include the rotor and I did notice that my rotor sat a touch higher than the old one and the magnetic ring needed to be "persuaded "on the shaft. (Not mentioned)

My idle was not as smooth as I wanted but it did idle where I wanted it to be at.

I am going to revisit my setup and look a few of these items over tomorrow to see if it's smooths out my idle more.

Thanks for the video link

 

[thejeep007]

No problem, stumbled across it over the winter myself. Idle has been rough for a few years. Hope this info works for us both!