1968 383 bore help

[69 Cuda 440]

CP Motorworks,

All excellent points, but if a customer is 'low' on funds and needs help, you can
make it work, as long as the Cylinder Bore is not way out of round {ie; oval-shaped}
or exceeds general 'good shop knowledge' parameters.

A proper cylinder finish by a Machine Shop using a Sunnen Cylinder Hone with
correct stones can create a decent cross-hatch for an adequate oil-sealing finish in a worn cylinder.

The customer just has to be informed, that this will not be the 'optimal' way to go, but will be
functional for general use.

 

[RustyRatRod]

Why are you clammering on? No one's arguing with you. You're arguing with yourself. We all know you're a super genius. Move on already.

Your maximum will be determined by the difference between the bore and the piston skirt and the total clearance. One means nothing without the other. The max wear is usually right where that ridge is, from the rings expanding under pressure of combustion. Yes, if the majority of the bore is in "good" shape you can hit it a good hone (not a 3 finger hone in your drill) and a fresh set of rings in and it will run and drive decent.


Of course it depends on the application, but be realistic and honest here. If the bores are anywhere near .006" OOR it will smoke, use oil, be down on power, and have a short lived life.
A} nobody wants there weekend show car to smoke or be an oil burner.
B} the False economy of spending a little money to spend it twice later
C}Budget yes, performance no.
D,E,F not even close to being acceptable.
This is what most people dont understand,and then they claim the machine shop screwed them (and yes the often do) when the results are less than stellar. You cant have those conditions and expect it to not cause a problem.
This 413 had less than 500 miles on a refresh from a "Mopar Shop" no less and the owner could tell it was down on power, using oil, and not right.
Bores were only .0015-.0025" OOR and no, the rings werent sealing.

Modern rings -as I'm sure you know- are made very precise, and do not cover up bores that are out of shape. This isnt the '60's or '70's where it takes 1k miles to seat rings to "wear" them in. There is a good reason modern engines go the miles they do.

 

[Darren]

I will get the bores measured and post. thanks