Looking for a good FE or FT block dated 8 G, H, or J. 390 (FE or FT) or 428 (FE). Please let me know if you can help.
Not sure if you know 390 blocks cannot be bored to make a 428.
^This site should be your new best friend for everything 428CJ related.
I highly recommend becoming a member of the forum there.
Also, a great resource for parts ID.
Different people have told me different things on this. I was told as long as there’s enough material on a sonic test it was fine and that if I use a truck block it has the extra reinforcements like the 67 and later 428s have. Is this not true? Alternatively couldn’t I bore as far over as is safe and make the rest up with stroke to get as close as I can to a standard 428? Ideally want a 428 block but keep coming up short as far as dates. Plus the ones I do come across cost as much for just the block as it would cost me to build and install a 390 that looks the exact same.
Not true. You get to a 428 w/a special crank, flexplate, damper. The site Mike linked for you is a great resource. You can put a 390 where a CJ 428 should be, but it will only look “the exact same” to the untrained eye.
A 390 block would need to be bored .080 over to make 428CI at the very least it would be an over heating nightmare but as Royce said cant be done.
Who ever is telling you that is just plain mistaken. There are no heavy duty truck blocks that can be bored that far. There are no 390 block that can be bored that far.
There are real 428 blocks that can be bored to .030" over or maybe .040" over if you are lucky enough to find a really good one. You need to be looking for a real 428 block that is standard bore and then have it sonic checked to see if it can go oversize enough to clean up. If you have $2500 - $3000 to spend than you are likely to find a good one. Fortunately 1969 model year was the most common for 428 blocks. Any 428 block is the same as any other 428 block as far as non - CJ, CJ, SCJ, cop car - even granny’s Colony Park station wagon has the same 428 block as any other 428.
Maybe I can help sort some of this out? A little surprised to read the hardline comments but I do understand. Over boring can be a huge waist of money if you end up with a weak block, overheating, poor ring seal etc… Also I have seen many spoofed 428 blocks on EBAY etc… that were 390’s. Need to stay away from those completely.
A real 428 block is anything that has a 428 stamped inside the water-jacket, passes the “Drill bit” test and of course has the standard 428 bore. However there are some (limited few) 391 FT blocks that were cast with 428 water jackets correct? My understanding is that this is what you would need in order to consider a 428 bore. Or is that still up for debate too?
No - not correct. Internet legend that is just plain mistaken. To be extremely polite.
The safest answer is no you can’t bore and stroke a 390 and make a 428.
In theory only, some have claimed to find 390s with the inner cores of a 428. It could make sense as Ford mixed and matched pieces as they cast them, especially when there were problems on the line.
However, I have sonic checked and built many 428s and 390s, and my experience is that some 390s shouldn’t even be 390s, never mind 428s, and I haven’t found a single one that I would bore to 4.13 unless building a trailer queen and even then I wouldn’t put my name on it.
In fact, although I am much more conservative with strokers, many 428s are dicey with an overbore. As a rule of thumb, C scratch is best (almost always good) followed by A scratch, and the CX scratch industrials are so random you never know what you will get. My own .025 CX was as nice as any C scratch, but I turned away two others because the entire bank had the casting shifted to make the thrust side too thin to trust.
Finally, a truck block IS a car block, no difference until later reverse 105 blocks, which would be incorrect for the car, and still not a 428
One of the car magazines in the 1990’s (Mustang and Ford High Performance maybe?) had a series of articles on building a “Poor Man’s 428” using a “thick walled 390 block”. They went through a bunch of 390 blocks and found the best one they could after paying to have many of them sonic checked. They bored it and then built up the engine. In the final installment they grenaded it on its first dyno run as a thin cylinder wall split and milkshaked the oil.
Thus the guy building the engine truly became a poor man and he still didn’t have a 428. Back then you could buy a junkyard 390 engine complete for maybe $200. These days even good 390 blocks are hard to find. I bought one a few months ago for $200 because it had a 8A date code and had magnufluxed good with standard bore.
428CJ blocks sell for more like $2000 these days in standard bore and are still worth it.
$2500-$3500 is what I’ve seen.
Lucky that you are not trying to find a 427!
Maybe but still pain added to an already painful situation.
KTL still has the one listed on the facebook page for 2300.00 It is a Dec 1 1965 block with a 1U crank and standard bore pistons and rods. I’m no expert, but I would think it would work for you, and the price seems quite fair from a reputable biz.
It may just be me but I don’t feel right putting a 65-66 block in a 69 car.
That’s interesting. Not an expert either on Ford date codes but the 428 didn’t “officially” come out until 1966. Perhaps 1966 is the vehicle module year so a 1965 cast block would make sense? I was hard core searching for 428 blocks last year and though I had all the nuances figured out. In the end you need to look at all the date codes, foundry marks and scratches to keep everything in perspective. My goal is just a sound block for a high output stroker vs a period correct piece.
I don’t know about other parts of the country, but here in the Pacific North West it was a popular swap to increase towing capability’s of F series pick ups. I have had 2 F-250s that had 428’s in them. Back in about 2006 I had a 73 with a 68 T-bird 428 and recently I had a 71 with a 70 428PI that I harvested for my “Q” code Cougar. I looked at several others that I either did not like what I saw or the price was out of line or above my budget. One was a 69 CJ with an aftermarket intake that I would have bought. He thought he had a deal on it but it fall through after I got the one with the PI. I didn’t have the budget for a second one.
Kwwp your eyes open, one will fall in to your lap.
The 1966 model year started officially at Fomoco on July 4, 1965. By that time 428 engine blocks for the 1966 model year had been made for 30 days or more.
There would have been far more 428 blocks cast in the 1969 model year which was the high point of 428 production at Fomoco. The block and crankshaft are not specific to a 428CJ. Every 428 from a cop car to a 428CJ to granny’s Colony Park station wagon used the same exact block. (Yes I know the 428 was phased out in Colony Park wagons after 1968 model year).
I guess given the post title I didn’t think it was going to matter as to date coding. I mean if you were thinking of trying to use a 390 (which it has been stated wouldn’t work anyway) why not a different date code.
Maybe they used a 65 date code block in a 69…using NOS parts 
(just kidding)