Are all 429/460 engines internally balanced or are certain years externally balanced? The reason I am asking is that ever since I put a new flexplate on the 460 in my truck, the engine has a bad "shake" between 1500 and 3000rpm.When I ordered the flexplate, I ordered it for what the engine came out of (73 Lincoln).There's a counterweight on the new flexplate. It's been a while since I put the engine in and can't remember if there was a counterweight on the old flexplate.Could the balancer possibly be shot? Any help would be appreciated. Thanks.

 

[font size="1" color="#FF0000"]LAST EDITED ON 08-Feb-01 AT 10:00 PM (EST)[/font][p][font size="1" color="#FF0000"]LAST EDITED ON 08-Feb-01 AT 09:55 PM (EST)[/font]

the 460 429 were both internaly and externaly balanced the earily 460 429 were internal look on your harmonic balacer to see if it is perfectly round in the back .
if it has a lobe or weight on one side if it dose you might have a later 460 429 but sounds like you have a internaly balanced motor with the wrong flexplate or you might have lost the weight off your torq converter what happned to your old flex plate and get the numbers off your block . they will be on the passenger side of the block directly below the last spark plug and should look somthing like D3VE-A2? somthing like that that will tellyou what block you have and some of the more experts around here can tell you what exactly you have



i ask what happned to your old flex plate because if it blew up it could have knocked off a counter weight on your torqconverter


oh and to check to se if the balncer is shot pull out your #1 spark plug and turn the motor over buy hand till the piston is all the way up and look at your balancer the timing mark should point at zero or with in a degree or so.
and check the rubber bushing in the balancerit should all be there not rotten and falling out

sorry i kep thing of things that have happened to me you might be missing on a cylinder in the morning start your rig and go out and grab each exaust port on the exaust manifold your are looking for a cold one or one that takes a while to warm up

i will quit now
hope this helps

 

The # on the block is D1VE-A2B,which my casting # book lists as 429/460 from 68-78.The came from a 73 lincoln,I saw the car in the junkyard I bought the motor from. I replaced the flexplate because the guys at the yard bent the one that was on the engine.I'm not near my truck right now,but I'll check the balancer this weekend. It's not missing on any cylinders either,the headers get hot real fast.

 

They were externally balanced starting in 79 its very obvious when looking at the balancers GOOD LUCK