Help with 390 selection

[PaulProe]

I am looking to rebuild a 390 for use in a Cobra. I have two used engines available to me.

1) Casting D3TE, Date Code 4F23 Head Casting D2TEAA the engine has a 2bbl manifold on it and a flexplate, indicating auto. trans. The oil pan is a front sump. From the date code, I come up with July, 74 which would indicate a truck engine?

2) Casting C?AE-A, Date Code 5A13 Head Casting C4AE the engine has a 4bbl manifold and a flex plate. The oil pan is a front sump. The date converts to Jan, 65 , the engine comes from a 65 Thunderbird but we don't know its history.

Which, in your opinion, would be the better choice and why? What is the going price for a used 390 for rebuild?

Thanks for any help

Paul

[flwolfman]

The truck block weights about 20 lbs more than the car block and the truck crank weighs about 10 lbs more than the car crank. with larger snout and heavier counterweights. The ft crank is externally balanced also. The ft block also uses a larger diameter distributer than the fe.

I would stick with the fe thunderbird engine myself. Just my thoughts,

Jim

[jschiller]

Jim is right in his description of a 391 FT engine but they were fitted to large trucks, not pickups and such. I doubt a 391FT would have been mated to an auto trannie in a large truck but you never know. The oversized crank snout and large distributer hole are the dead giveaways. As long as the blocks have 3 bolt engine mounts, the early FEs had 2 bolt, I would go with the one that has the closest bore and crank sizes to std to allow for safe cleanup. You are probably going to throw the oil pan and manifold away anyway. Either block is good for 375-400 HP with little effort.

[Power Surge]

Paul, check out this link...

http://cgi.ebay.com/ebaymotors/FORD-...QQcmdZViewItem

I bought my 390 from these guys. I was VERY impressed with the communication and helpfulness from them before I bought it. It arrived in less than 2 weeks, crated to my door, for $3200. I currently have it in the car, and it performs FLAWLESSLY. Everything about my motor is perfect. I could not ask for any one thing to be better.

If you're looking for a low dollar quality 390, I recommend contacting them.

BTW, I have nothing to do with them, I am just a really satisfied customer.

[PaulProe]

I doubt the block is an FT, very unlikely it would have been coupled to an automatic.

I am pretty sure it is a 74 - 390 probably from a F150 or similar.

Still torn, which is better choice, the 65 or the 74?


Paul

[Lowell W]

I don't know anything about FE's but if you have any concerns about smog compliance relative to date of engine manufacture, the '65 might be a better bet. There are a lot of other threads on CC which deal with that topic.

Lowell

[lineslinger]

Paul
With you and I being in such close proximity to each other I may have some alternate sources for you to check out as well as some other information.
I just recently finished a 427 build and have done some serious due diligence for FE development and research in our area.
If interested send me a PM and I would be more than happy to share with you what I have been able to learn about big block sourcing in our neck of the woods.
Mark in Clayton Mo.

[ZOERA-SC7XX]

There were automatics in some 70's LN series medium size Ford trucks...I used to work on them. Trannys were made by Allison I think.

[My427stang]

D2 heads are small port but a good chamber, however they have a different exhaust port (like the C8AE-H and C7AE-A too), so headers may not line up depending on what you are using.

My guess with a Cobra, you'd want the early exhaust port

My experience with the 390 blocks, pick the one that is in the best condition. However, if you wanted to really be serious about it, magnaflux both and sonic check and the one with the thicker walls would be what I'd use

(Sorta, in real life if the first one was good, I'd stop there) LOL

[FFR428]

With keeping the date codes in mind the 65 might be better smog exempt wise. Plus the C4 heads are lowrisers which I've always liked. The D2 heads are the same casting as the earlier C8-H' MR's. The D2's have induction hardened seats for unleaded. BUT some of the D3 block castings have nodular maincaps unlike the grey iron caps the C4 block most likely has. You can see the "ladybugs, warts or bumps" as they are known as on the maincaps. You should also see a brinnel indentation on the side of one or more caps. Tough call either way. I'd drill bit test both blocks to see which has the better cyl wall cores. The D3 block might have thicker wall cores possibly. I've also seen lots of C4 block casting that got the crossbolt bosses also. Some of these have had thick walls also. Guess the main point I'm trying to make is you'll need to look inside to make your decision. Both could be very good choices. JMO,

G.

[My427stang]

Watch calling the D2/C8 heads with the med riser port location "med risers" they are actually 390 GT heads with an exhaust port for the Fairlane.Mustang body

Not even counting the exhaust bolt pattern options, they are very different heads all together and the intake port is hardly a med riser in flow potential, although located in the same place, they are narrower, have different valve spacing, the exhaust port is completely different and the chamber is completely different (Although the chamber is actually real detonation resistant with lots of quench pad and an almost kidney bean shape compared to any other FE)

Matter of fact, if you look at the exhaust port on a C8/D2 head, you'd be amazed at the valve bowl, I have no idea how they can even run on a 390, the seat to bowl transition is horrible, like 60% of the seat area

C8 / D2 have a good modern chamber, but need a LOT of work to make big power. Great torque head if you have a header combo that will match, but a standard FE header will not seal against the head

[farmallmta]

Originally Posted by Power Surge

Paul, check out this link...

http://cgi.ebay.com/ebaymotors/FORD-...QQcmdZViewItem

I bought my 390 from these guys. I was VERY impressed with the communication and helpfulness from them before I bought it. It arrived in less than 2 weeks, crated to my door, for $3200. I currently have it in the car, and it performs FLAWLESSLY. Everything about my motor is perfect. I could not ask for any one thing to be better.

If you're looking for a low dollar quality 390, I recommend contacting them.

BTW, I have nothing to do with them, I am just a really satisfied customer.

I agree with you and also highly recommend them based on my dealings with them! I purchased a set of nicely modified 406 heads with undercut stem SS CJ valves from DJ Machine. My local, semi-retired and extremely finicky machinist inspected the work closely and was very complementary of their workmanship. He pointed out a couple of minor things he does differently than the way they did them, but rated the heads as very well done. And they really helped make my 390 come alive BIG TIME!

So, on a scale of 1 to 10 with 1 being "do the world a favor and blow the f***ing shop off the face of the earth" and 10 being "shop owners and workers may collect $200 and automatically enter Heaven and sit at the right hand of God whenever they please," I'd say DJ Machine gets a 9.5 for knowledge, 9.5 for accurate description of product, 9.5 for customer service and responsiveness, 9.0 for care and attention to detail, and an overall 9.2 for helping make FE parts available and affordable.

And I'm darn particular! Not bad for an outfit I've never met in person, having only talked to them on the phone!