Is this normal?

[beanhead]

Hello..again! This engine seems to shake around a bit at idle, and it's kind of irregular. Wondering if it's just part of life with more than stock cam? 440/ comp 274xe(230* @ .050 intake, 236 @ .050 exh, 110* LSA) Right now at a touch under 20* initial @ idle(tach crapped out so I'm not sure of rpm, sounds to be around 800ish) pulling fairly steady 14 inches vacuum...if you listen close you hear it slap the header against the t-bar when it shakes a little more (needed a few more dings!) Sometimes it doesn't do it much at all, and then next time I start it it will..Any ideas are appreciated thanks! This thing likes more initial timing BTW, I have under 20 because I have not gotten the correction plate for the distributor yet and my total as it sits is 38*..demon 850 on top, mopar elec ignition..and if I decrease the idle speed it does it more..thanks again everyone

 

[Mike67]

Kinda looks like a broken mount...

 

[beanhead]

Kinda looks like a broken mount...

That was my first thought too but the mounts are good(maybe not for long though lol)

 

[Mike67]

Have you verified you dont have a miss/arcing?

 

[beanhead]

Have you verified you dont have a miss/arcing?

No, double checked correct firing order and put my light on each wire to make sure there's a pulse, what's a good way to check for arcing or miss?

 

[Mike67]

Turn the lights out, close the door...youll see it if its jumping. DONT REACH FOR IT!!! LOL!

 

[beanhead]

Turn the lights out, close the door...youll see it if its jumping. DONT REACH FOR IT!!! LOL!

You mean exposed arcing between the actual wires somewhere? I'll try that tonight after dark thanks

 

[440+6]

Spray mist of water will help find any arc.

 

[Mike67]

Yes sir. Look around the boots & headers.

 

[beanhead]

Thanks I'll give it a look

 

[the mississippi madman]

Does it actually miss when it shakes or is it just shaking every second or so, because I couldn't hear the motor rpms change on the video

 

[beanhead]

Does it actually miss when it shakes or is it just shaking every second or so, because I couldn't hear the motor rpms change on the video

RPM seems to stay steady...but as you can see the shaking fluctuates. Here's a clip from the tailpipes...it doesn't sound to me like there's a miss but I could be wrong. It's easier to hear with good speakers, thanks

 

[beanhead]

Ok.....fired it up and watched it in the dark, didn't see any arcs (and I'm an electrician by trade I've seen more than I care to!)

 

[wsutard]

I will be interested it see more responses to this. My engine also tends to shake more than I think it should at idle but people have said "its due to the aggressive cam". I havent looked further because it isnt causing issues and I dont really want to find a problem...

 

[beanhead]

I will be interested it see more responses to this. My engine also tends to shake more than I think it should at idle but people have said "its due to the aggressive cam". I havent looked further because it isnt causing issues and I dont really want to find a problem...

Yep I hear you...next I will check for vacuum leaks, to rule that out at least

 

[beanhead]

Welp...no vacuum leaks..any other ideas out there? If this much shaking is common I'm cool with that too, just want to know I'm not hurting it

 

[Dennis H]

Is that the exhaust bumping something? 750 RPM or so? Find whats bumping and adjust. Maybe play with idle. Seems like a near normal characteristic to me.

 

[beanhead]

Is that the exhaust bumping something? 750 RPM or so? Find whats bumping and adjust. Maybe play with idle. Seems like a near normal characteristic to me.

Ya, I think it's kissing the PS torsion bar, when it shakes harder...I'm beginning to lean towards an irregularity in the ignition, I put the timing light on each wire and looked at the light and it doesn't seem to be a nice even strobe on every wire..on some of the wires it seems like it blinks faster or misses a blink and on some it's consistent

 

[miller]

Whole lotta shakin' going on?
Sounded like as you think, probably...ignition. Either some bad plug wires, not wired right, or cross-firing, for whatever reason.

 

[440+6]

Take a good look at your cap and rotor, might be arching in there.