Well, the restoration continues. It seems like forever, but I think I'll be done in the next 4 weeks.

Anyway, today I was in the shop and they started the engine. It started up easily but I noticed a lot of overall shaking - the compressor,several of the Paxton pieces, etc.Keep in mind it ihasnot been final tuned but I wondered if this was normal. If not, could this be caused by the engine mounts (which were replaced) or something else. Or perhaps they just have to go over everthing and thighten the bolts down once again. Or perhaps this is normal.

Does you engine shake much at idle?

Thanks---

 

Not at all.

 

what kind of cam are you running? depending on the cam idle specs, you may just be seeing the byproduct of a lopey cam.

 

The engine is totally stock exscept for the supercharger

 

maybe a valve too tight

 

What is the car physically idling at (i.e. go LOOK at the tach). If the idle is chopping up and down and you claiming the internals are stock, then I would check your wires to make sure you're running on all 8 cylinders (did a boot come off?). Also have they adjusted the timing yet? As Brandon mentioned, what about the valves?

There are several things it could be, and knowing what its idling like currently would help.

 

id start with the timing and firing order or like mojoe said bad wire or plug can do it too

 

Hi !

My guess it's probably not running on all 8 cylinders.

get players to not be electricuted .... feels bad

then pull ignition cable from 1st cylinder while the engine is running. doesn't matter if you disconnect the cable at spark plug or at distributor. Same thing.
If the engines idle goes down or more rough, then you know this cylinder was working before you pulled the cable.

If there is no change in idle, then this cylinder is running dead.

Check one cylinder after another. (connect cylinder 1 and disconnect cylinder 2)

If you find a dead cylinder:
a) swap ignition cable with a known good one. problem gone-> twas the cable
b) swap the spark plug with a known good one. problem gone -> twas the plug
c) measure compression on this cylinder or better on all cylinders ....

most importantly: get those spark plug players. they're isolated. It's safe then. If you pull it with your bare hand you'll get sparked and I do not want that.
I never heard of some1 being killed doing that. It happened to me quite often and it's like you touch a cow fence. But as I cannot be made reliable for your injuries: GO SAFE. The safe way would be to measure idle. switch off. then pull the cable. But you have a lesser good idea on if it got worse or not.


Kalli

 

I've seen this happen with a dead cylinder, screwed up timing....OHHH man one time we were working on a 5.0 HO and used a standard 302 firing order...ooops she uses the better 351w firing pattern. The thing was shaking so much the car was hopping.

 

how is it when you increase the rpm because if it does it thought the entire range i would suspect timing if only at idle i bet its a tight valve cause the engine will be spinning so fast that it won't have time to bleed that compression so it will seem good but it will suck at idle