I bought a 67 mustang coupe with a 289 A code. After tear down of the motor because i was told it spun a bearing back in 82. (Yes this car has been sitting in a garage since 82.) i discovered that the rod journal is 2.0693 and is scored pretty deep. According to a bearing manual the min diameter of the journals can only be 2.0832. i see a slight problem here.

I should probably state my goal as well, i am building a show car and want it to be as close to its show room debut back in 67.

So my question is: can i replace the crank with a 3" stroke instead of the original 2.870 without effecting the restored value of the car?

Also there is a lip on the cylinder walls at the top, does boring over the cylinders effect the restored value?

 

My 65 uses a 302 crank (not a 5.0 crank) and it looks just like the 289 externally, the balancer even slides on. So, really nobody would know you have it unless you tell them or they take the pan off. Most people do not deduct for engine internals, the date code on the block is about it. That date needs to be within two weeks or so of your cars build date. We really dont have "Matching numbers engines" unless you have a K code or Shelby car, then it really matters because the VIN is stamped into the block itself.

The "Ridge" on the top of the cylinder wall is kinda normal on older cars, we had a special tool that was used to cut that ridge out from the top, it was even used with the pistons in the block.

Piston Ridge Reamer.


It allows one to push the pistons up from the bottom with the crank in place with the motor in the car. It was not uncommon to flash a hone through the holes to replace the cross hatch and install new rings.

They can be borrowed from some parts stores.

 

What you do to the internals of your motor should have little effect on the originality of the car. What with the ridge and the crank damage, something has to be done to the motor to make it useable. Boring and stroking the motor to some degree to make it once again serviceable would be okay IMHO. Don't bore over .040 or you run the risk of having an engine that is prone to overheating.
Best,
Al

 

I would just get the engine rebuilt as close to stock as you can.Restored value just depends how much someone will pay for it.Nada guides shows a max of like 26 grand but being a coupe that's not a k code or big block probably won't go over 20k.

 

Thank you guys, you have taken my concern away. This is my first restoration and I was unsure. Thank you

 

A 289 and 302 are pretty much twins unless you take one apart to see the bore and stroke or pulled the starter to check the casting codes on the block.