Author Topic: 67 Gt500 427 PI block & crank  (Read 453 times)

68krrrr

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67 Gt500 427 PI block & crank
« on: September 18, 2019, 11:30:51 PM »
Looks to be an early Feb 67 block, has the A scratch & C6ME casting for $1800

https://offerup.com/item/detail/423659149/

2112

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Re: 67 Gt500 427 PI block & crank
« Reply #1 on: September 19, 2019, 12:35:23 AM »
At .060" over, I would want it sonic tested for wall thickness.

pbf777

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Re: 67 Gt500 427 PI block & crank
« Reply #2 on: September 19, 2019, 10:09:35 AM »
     At .060" over, I wouldn't bother,.................THIN!     :o

     Scott.

shelbydoug

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Re: 67 Gt500 427 PI block & crank
« Reply #3 on: September 19, 2019, 10:37:35 AM »
It's not a 427 block. After a certain date, all FE's had 66-427 cast into them.

All FE's are borderline thin at 30 over including 427 blocks. 60 over is a gonner unless you sleeve all 8.

You need to hone them out, not bore them out. You can have pistons made for them in any size now. Ask Randy here. He's THE piston guy.

1967 eight barrel

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Re: 67 Gt500 427 PI block & crank
« Reply #4 on: October 01, 2019, 01:45:49 AM »
Another misnomer. Not all blocks are thin at .030. However, 427 and 428 blocks are often only good to .040. I have even seen 390 blocks that are only good to about .030.  ALL FE blocks should be sonic checked before you start any machine work on them. I just went through this with my vehicle.
Very expensive when they fail.  I wouldn't buy a .060 428 block. Even a fresh .060 bored block. Many are less than .100 thick on the major thrust side.
You wind up with poor sealing rings and cylinder flex. They wind up splitting like my block did twice.
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shelbydoug

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Re: 67 Gt500 427 PI block & crank
« Reply #5 on: October 01, 2019, 10:36:29 AM »
Many Ford blocks exhibit core shift in casting. Not just FE's.

Theoretically and in practice to a large extent Ford's boring bar recentered the bore and in many cases, not just some, thrust walls were around .100" new with a standard bore.

For a production engine that was ok.

It would be wise to consider all thin until proven otherwise I think. The commonality of stroker kits these days makes it even more important to sonic test the block first.


The 289's have such little torque and such a short stroke that lots of racers were going .125 over without ever sonic testing them with decent results.


Cleveland blocks are some of the worst. When they were in service Ford only sold .002 over pistons because that's all that was safe.


My two 67 427 blocks were only good to .017 over. I think Ford just considered them throw away items at the time and many of these issues didn't become apparent until they discontinued supplying new castings and everyone was stuck rebuilding what they had.


428's may seem to be better because there were more made so you have a better chance of getting a good one? The biggest complaint with them is running hotter after a rebore. That's a pretty common discussion even here on this forum.

Of course ANY FE is going to run cooler in a chassis that has adequite air circulating around it. It seems that is probably the largest problem in a Cougar/Mustang chassis, i.e., a really tight fit to the engine compartment. Louvered Shelby hoods do help a little but those heat waves you can see pouring upward through those louvres always freaked me out in traffic.
« Last Edit: October 01, 2019, 10:41:49 AM by shelbydoug »