Hello
 

Hello all,

I am new to this site and to membership in any car group for that matter. I have been playing with cars for some 43 years and most of that time with fords because I liked to be different and most of my early friends had chevys. I decided to join this site because I finally need some wisdom from you guys that have worked with the high performance FE motors. I have done a lot with small blocks but not a lot with FE's. About 20 years ago i bought a '67 Shelby GT500 in class 1 condition and have only put 15,000 miles on it since then. I have recently decided to sell it and wanted to freshen up the motor for the prospective new owner. I knew it had a 427 sideoiler in it but had been told some things about the internals that when I took it apart I discovered were not true. It was running pretty good save a little smoke from the number 8 cylinder which cleared after about five or ten minutes of running. I figured i was going to be in for a top end rework but was going to totally disassemble the engine just to know what I had. I found out I was runnng 60 over pistons and that the clearance on the rod bearings was close to .004 with plastigage. My question for all of you is: I have read it is not a smart thing to run a 427 with any more than .030 overbore, why if the wall thickness is still over .100? I have had the walls sonic checked and found nothing below that. What do these engines do when overbored? I have heard that they overheat, but this one did not run over 180 whether I ran it on the highway(4500rpm at 55) or in stop and go when cruising. I admit I did not drive it very far at any one time, but at least an hour or so each time. Any comments would be appreciated.

Jeff

Fords for fun!

Mod Note.... moved to FE Forum.

First, welcome to the club.
I believe you made a typo here...either that or are runing 6.10:1 gears. :)
Your block must not have any core shift. Anyone else running .060 over on the street would have serious overheating problems or broken a cylinder wall or two. I suggest you have the block sleeved to stock if you can locate some pistons and rings, or take it to 4.250, BB Chevy size. Pistons and rings are readily available in that size.
Plastigage will give you a ballpark figure of bearing clearance, but measuring the crank and rod or main bore with a bearing inserted will give you the true clearance. .003 is pretty standard for an FE.

Dan

FE block thickness
 

Personally, I don`t consider .100" thick enough for a FE block that will see hard use. Some may, but I don`t. I have been drag racing FE`s for over 30 years, and I to keep the cylinder wall thickness closer to .150". Now, I mainly run 428`s, and I will admit that it may well take checking a few blocks to find one with minimal core shift, and thick walls, but they do exist. In my 428 Fairmont, I have one cylinder wall split, even with .150" + thickness, so the thought of running .090-.100" cylinder walls makes me rather uncomfortable.

Neither do I...however, 427 cylinder walls are often only .100 thick. I believe Ford considers this the minimum allowable thickness.

Dan

Are you sure you have a 427 in your Mustang? The reason I am asking is because I had one in the mid 70"s and I only had a 428 in mine. A 428 has a little thicker walls than the 427, I think.

Clois