Hi,

I have a 68 RS SS that is pretty much original except the engine has been replaced at restoration ca. 2011. Code comes back as a 1971 402. It runs well. I've been working on a tune up with new plugs, cables, points, and rotor. The points I bought didn't work (wouldn't start). They came with a condenser but the ones I removed had the points and condenser separate. I cleaned the existing points and everything is fine but I'm confused about the timing and dwell angle.

At 800-1000 rpm or so the mark on the balancer is close to the top and not near the gauge. If I turn the distributor to around 16 above TDC it runs rough and at 0 it won't run. So I put it back where it sounded better and the rpm went up and I locked it back in. My new timing light does dwell so I tried that and saw 90 degrees. I read it should be closer to 30. Turned the screw until I saw 30 but it ran really rough so back to 90 and everything seems good again.

When I bought the car I had a mechanic check things out and he said it sounded like there was a non-standard cam. Not sure exactly what that meant. Could that account for the numbers? It's running fine but when I find the right points and try to start with the initial gap it might not start if that's the wrong gap. Need to find them first but just feel like I'm missing something.

Thanks for any advice.

 

Might be the dist. is in wrong a tooth off on the cam gear. Pretty common mistake trying to drop it in and catch the oil pump drive..
Check the rotor position at #1 TDC compression stroke to see if it's in the right position.
If it was mine I'd toss the points dizzy and swap in an HEI,much more reliable and far less maintenance.
Pretty much set it and forget it and a good hot spark.
Working from memory dwell should be 32 points gap .19 and timing 4 before TDC,maybe a little different with a performance cam but not much.

 

Ok. Thanks for the reply. It makes sense. Probably above my skill level to fix it but I can check TDC compression and rotor position. Regarding HEI; I'm kind of stubborn about keeping it original as possible but nobody can really see it and I'm not getting it scored or anything and I can always change it back so I'll look into it. Installation looks like something I can do. Even if I install electronic ignition do I need to get the distributor figured out? I'm answering my own question on this one (yes). Pertronix? Any recommendation for this engine?

The cam wouldn't make that big a difference. Got it.

Thanks again for your help,
Doug

 

Hi,

A friend of mine who has done this before and we took out all the plugs and the driver's side valve cover, rotated the engine to TDC on the compression stroke and the rotor was pointed towards #2. We lifted the distributor and pointed it towards #1 and rotated the engine just a bit until it fell in place at which point it was pointed pretty close to #1. Buttoned everything back up and timed to about 10 before TDC and that engine has never run smoother. It still runs better at a higher dwell angle than recommended but the points are a bit worn. So you were right! Thanks for your help.

D.

 

Awesome!