bdnwtkfg

Need help.
I have a 410 Mercury Block that has a 428 crank, and bored to 428 specs. It was put into a 72 F250, but was not the original block. . . It has been given to me by a real good friend. . . & I know its a good motor.

My question is: what is the difference between a 410 & a 428CJ Cobra Jet block? . . . or is there a difference.

I am placing it into a 1968 Mustang Convertible, previously a 6 cyl.

I have a Bullitt proof Currie, Lincoln Versailles, 9" rearend, new V8 Big Block, 1" shorter springs and new front end from Mustangs Plus, Front & rear sway bars (although I am being told the rear wont work with the versailles rear end) and I assume I will need to stiffen the shock towers as well. . . all that said, I am curious about the engine. . .

any help will be GREATLY appreciated!

THANK YOU IN ADVANCE!

Big Dave
(so calif)

FFR428

The Mercury 410 was a 4.05 bore 390 block and a 3.98 stroke crank. The 428's were a 4.13 bore block and a 3.98 stroke crank. The 410 was a 66-67 Mercury only engine option. And from what I understand the blocks are thick enough to support a 4.13 overbore. But I've never been able to verify that personally via drill bit test and sonic map. If you would like to check for us that would be cool. You have to remove a few block freeze core plugs to access the cyl wall cores. Then you use the shank end of the drill bits to gauge the gap between the cyls inside the block. If a 13/64" drill bit shank is a snug fit then yes it was cast with 428 cyls. Standard 390 blocks have a typical 17/64" drill bit fit snug. A sonic map of the block is the best way to tell the REAL thickness and might be wise if you find only 390 wall cores in the block. Coreshift is another factor as some blocks were worse than others. Crapshoot pretty much. There are also cranksaddle and webbing differences between the blocks. Some were heavy duty and some just standard. They are all good tho.

bdnwtkfg

Sorry for being an idiot here. . . but I've been planning on doing a 351W, and was just given this 428. . . and there is no replacement for displacement!

1. I will check and get back to you on the dimensions. . . I will be going thru it and freshening it up real soon!

2. Assuming a.) its been bored, b.) it has the different crank. c.) the math shows it at 428. Is the 410 block stout enough to be ran as a 428, and do the CJ heads make it a CJ?. . .

3. Is this a good canidate for a Shelby Clone. (not to sell. . . it will be my daily driver. . . because I cant imagine driving a real one on the Un-insured streets of Southern California!


4. any info re: a Tremec T5 behind a FE motor?

THANK YOU for taking the time to help me!

Big Dave

FFR428

Dave you first need to see what cyl wall cores are in the block. If it has 390 wall cores and it's been overbored to 4.13 that's not so good. The cyl walls would be pretty thin. But if it was cast with thicker 428 cyl walls and has been bored to 4.13 std 428 you should be fine. So hopefully the shop that did the work sonic mapped the block before hogging it out.

A few things besides the CJ heads make up a 428CJ or SCJ. Without writing a small novel check this site. It's the best 428 CJ-SCJ info site and forum out there.

Mustang 428 Cobra Jet Registry Click on component ID. This will bring you to another page with a list of engine parts. Click and read away.

Quickly there is a way to tell a 66-70 production 428 block from the outside. Most will have a sandscratch A, C or S on the rear of the block. You'll see pics of this on the CJ site. This does not apply for later service blocks as they had no sandscratch on the back. The 428 casting numbers were also used on different bore blocks so they are not the best way to ID one. So you need to look internally at a few things. Good reading tho. And any Q's come back and ask. Were all a bunch of gearheads here!!

Oh the stock T5 will shread pretty quickly behind a FE. The torque will spank it good. Maybe the World class T5 would hold up?? But most choose the TKO 500-600 or Richmond 5 speeds.