It wouldn't run at all if it was 180 degrees out...you'd be firing at the bottom of the stroke, when the mixture isn't compressed, so won't really do anything. You might get a backfire if the mixture ignites as the exhaust valve starts to open.
You could check the accuracy of the pulley notch by using a very clean, think stick in the plug hole and rocking the engine back and forwards to get it spot on TDC, but I think the fact that it's mostly OK and you're detecting the loss in power at 6 degrees ATDC, you're probably about right and you've not got a pulley with it's notch way out like mine was, so I would guess you are about right with how you've set it.
it would fire at tdc but the wrong one 180 is one turn of the crank but half of the cam
 
Didn't some one on here a while ago skim the piston heads to get over head being over skimmed?
Edit that might have been a diesel engine!
 
Didn't some one on here a while ago skim the piston heads to get over head being over skimmed?
Edit that might have been a diesel engine!
Skimming pistons is a very brave thing to do. Years ago, I used to do a bit of freelance mechanicing in a franchised garage. They had a TR7 in that had its head skimmed once to often. Their remedy was to fit two head gaskets, I advised against it but they went ahead. I left shortly after so I dunno what the result was.

Col
 
it would fire at tdc but the wrong one 180 is one turn of the crank but half of the cam
Hmmm. Are you sure about that? Given TDC is a crank-thing and it's measured on the crank shaft pulley, I always thought angles with respect to TDC were angles on the crankshaft, not the camshaft/dizzy. So 180 degrees out would be half a crank rotation, and a quarter of a cam/rotor arm rotation.

Doesn't really make a lot of difference - the engine won't run like that no matter how you measure it.
 
Hmmm. Are you sure about that? Given TDC is a crank-thing and it's measured on the crank shaft pulley, I always thought angles with respect to TDC were angles on the crankshaft, not the camshaft/dizzy. So 180 degrees out would be half a crank rotation, and a quarter of a cam/rotor arm rotation.

Doesn't really make a lot of difference - the engine won't run like that no matter how you measure it.
yes im sure people get it 180 degrees out as crank needs to turn twice to cam so often they get the tdc when cam is 180 out
 
yes im sure people get it 180 degrees out as crank needs to turn twice to cam so often they get the tdc when cam is 180 out
OK, you are specifically talking about the dizzy being 180 degrees out, then. I'd have described that as the ignition being 360 degrees out, given the 4-stroke cycle is 720 degrees. Not sure which interpretation @Landy1979 meant, but the result will be the same - engine wouldn't run at all. :D
 
OK, you are specifically talking about the dizzy being 180 degrees out, then. I'd have described that as the ignition being 360 degrees out, given the 4-stroke cycle is 720 degrees. Not sure which interpretation @Landy1979 meant, but the result will be the same - engine wouldn't run at all. :D
true but 180 our refers to cam position,when people say is it 180 out thats whats meant:)
 
Easy solution, to testing it.
Remove each plug lead at the dizzy and swop it with its opposite number. so one becomes 4 etc.
then try it again.
Happened to me after working on wifey's kit car.
Dunno how it happened but this sure cured it!
The longer way of doing it is to move crank to TDC, look at the valves for number 1 which should both be closed , then make sure the rotor arm is pointing to number one position on the dizzy cap.
If it ain't then make sure you know the direction the rotor turns in and the firing order, then reposition all the leads correctly.
 

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