Thread: Which FE block to choose?

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Hi guys, I'm new here, but have been building engines for 38 years, mostly the small block "C" brand.
I have a question for you FE experts. I have access to a half dozen FE blocks as I write this, and want to know which would be the best block to choose. They are all 390 blocks, as far as I know. I haven't put a mic to any of 'em yet.
First off, out of the six blocks to choose from, there are only 3 different ones of note. One of 'em is one with the mains that have the little nubbies on them where a guy could convert it to a 4 bolt cross bolt set up.
The second one is a block that has these verticle lines cast into the bottom part of the outside of the block. And, some have told me these particular blocks can be bored out farther than the others.
The third style is just a standard FE block with no odd identifiers.
Thanks for the help, and if ya need more specific info, just say so and I'll go find it.

After you get them boiled out, the only way to know which blocks have the thick bores is to get them sonic checked. There is a fast and dirty way to choose which ones to try... select the blocks that have the smallest gap between bores by trying to slip in drill bits as a gauge through the freeze plug holes. Typically 360/390 blocks can handle a .050-.060 overbore but the ones that can handle the .080 overbore to make it into a 406/428 are far and few between.

The block with vertical ribs should be late production (post 69 I think) or could be D2TE or D4TE casting. If all the blocks have four mounting points for the motor mounts, they are post 1965 blocks. before that they had two bolt motor mounts.

Thanks for the input LA. I'll check out the blocks that way. Is it advantages and worth the cost to use the block with the nubbies on it and make a 4 bolt out of it, or is it more hastle than it's worth?

Just a thought here FEforME.....i just recently finished up a nice strong street 390FE for a t-bird that is a 2 bolt .... as far as wanting to take it and have it made into a 4 bolt just ask yourself if its really necessary,i have a "decent" cam/compression setup in the 390 i just finished and it really dosent rev high enough to worry about changing to a 4 bolt main.....just tryin to save ya a few bucks on something you might not need to have done.

Good luck with it

Cross bolted is better, but it depends on what the intended use is. If you are going for a hot street engine that will never see anything over 6200 rpm, the money spent on cross bolt caps, machining and extra hardware could be moved over to stabilizing the valve train with end supports for the rocker shafts.

Besides, Dave Shoe over on the Network54 FE forum has an interesting project in the works right now that may be a cost effective way to get improved main cap stability without having to go search for expensive and semi-rare cross bolt main caps.

I do all the machining myself so it's not a big deal there, and as I recall, I've seen somewhere on the net someone out there is making the caps and spacers. I can't recall how much the caps were, but I'd like a good 7000 rpm engine when done, so maybe the cross bolt thing may be viable in my case.
Thanks for all the input guys!