Hi dose anyone know if a 289 motor is a inerfence motor the reson I am asking is I have a 289 an that I baught fron me friend an he put the cam in wrong 180 deg. an I don't know if I bent some vaules . Rick

 

Shouldn't be, unless you have a high lift cam and didn't check for interference when it was built. Would probably be best to pull the heads and verify that you don't have any marks on the pistons.

Jason

 

Back off the rockers and check for "short" valves.

 

If you put the cam in wrong, there is a good chance you bent valves. There's not a lot of clearance which is why the pistons are fly cut. If conditions are wrong, it WILL bend valves.

 

Hi Everyone : I took the motor apart an put the cam back in right, friend who put the cam in is a chevy guy lol ( do I need to say any more ) after I put the cam in right I did a compression check an I am getting 145 psi. in the motor so I put back together an it stated
an ran good I am pretty lucky . Thank you for all your help . Rick

 

put the cam back in right

U use a degree wheel to set it 2 proper advance? I'm more familiar w/the I6 & havin IT degreed to the 1st key @ 4* for a 265/265 cam...

Why use a 289? I hear there's no bottom end. Don't know why the 302 & 5 oh would give a better hole shot w/only 13 more cubic inches. May B their 'stroked' 289s?

 

180* out will not hurt the engine. Think about it, during normal operation the cam will become "180* out" every other crankshaft rotation. The only thing you did was shift the firing sequence of the engine over full crank rotation.

Turning the distributor 180*, or moving the plug wires 180* would have made the engine start right up and run fine.

 

No I looked at the cam gear an there were 3 hole one had a A, the other had a R, an a O I took the rocker arms off an put the right piston to #1 comp. an the turned the the gear so it would line up with the timming makes , an checked the comp. an I was getting 145 psi in the motor now. The 289 an the 302 are the same but the heads are diff. from what I can find out my looking an also it is what I could find for cheap . not to worried about the bottom end it will do what I want it is not a drag racer an I have a t-18 with a 205 t case . Rick

 

During normal operation, every other crankshaft rotation would be 2 rotations which would put the cam right were it was before rotation.
Even a single rotation of the crank would not be 180 out, it would just be in a different phase of the camshaft.

He wasn't 180 out, his timing marks were off and there not a whole lot you can do with the distributor nor the wires to remedy that.

 

The crank moves 2 revolutions for every single of the camshaft. Having the cam 180* just phases the engine "over" 1 crank revolution. Instead of a piston being top dead center on the compression stroke, it would now be on the top dead center of the exhaust stroke. As long as the camshaft was timed to a TDC, whether it was with the marks lined up, or 180*, no damage can occur.

The engine internals don't care either way. The only thing that does is the distributor. Simply rotating the distributor 180*, or moving the plug wires over 180*, or pulling the distributor out turning the rotor 180* and sliding it back in would have made the engine fire normally.

 

We are basically saying the same thing. I just noted that if you turn the crank 2 twice, the cam is back where it started. I only stated that b/c you used the term "every other crankshaft rotation" which would be 1 full rotation of the cam.

That's why I commented that he wasn't 180 out, that he just missed the correct marks.

 

Thanks for all the schoolin - love Bronks (& esp seein em on FTE!)

not a drag racer an I have a t-18 with a 205 t case
sounds pretty rock solid, Rick! Hope yer all set now!