Thread: 428 or 390

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Hi!

What is the difference between the 390 and 428 engines?
I don't know what type of engine I got.
I have some numbers here:
- intake manifold: C9AE 9425-B
- water pump: C9AA- 65F5
8505-A

1., Cylinder head: 9A23
2., Cylinder head: 9BB

Is there any lookable difference between the engines?

Any information about my engine is welcome!
Thank you!

You would also need to check the stroke. A rough measurement can be done through the spark plug hole with a small rod. Run the piston up to tdc, insert the rod and put a mark on it in line with the spark plug thread. Then run that cylinder to bdc, mark the rod at the same point off the plug thread. Measure the distance between the two marks.As you can see from Denny's chart, the 428 and 410 have the same stroke (same crank) but the 390 has a smaller stroke and a smaller bore. You will have to pull a cylinder head to measure the stroke...

Thank you guys!

Anyway, can we do something with the numbers?
I will check the block casting number, can it tell anything?

The numbers you gave are for the intake manifold and the water pump, on an engine of that vintage they don't mean much for determining what the engine itself is.... Can you get the casting number off the block? I believe on the FE engines it is above the starter.... Even that on engine from this year is not necessarily exact to say what it is. Then there's the fact that over the years, most anything could have been swapped into it during an overhaul or rebuild. Decoding FE's is not an exact science!!!!!

The C9-B intake is a pretty common item. As the guys mentioned a 69 part. Cast iron either 2 or 4 bbl as it came both ways. The C9AE-8505-A is a 428 CJ waterpump and could be worth a few bucks to the resto numbers crowd. The heads you have given the date code.....there is a casting number like the other C9 #'s you posted. Could be C8, C6 etc...The 9A23 on the head is a 69/Jan/23rd date code. The 9BB is most likely a 9B8 not a B. 69/Feb/8th. Heads use a 6090 humber so look for Ex: C8AE-6090-H as an example. That will be located between the center two spark plugs. Dave is right on the stroke check. You can put on TDC and remove #1 and 4...that will give ya both TDC and BDC. Yank the head to measure the bore. You may or may not find a casting number on the block. The date code is below the oil filter adapter...same format as the heads date code....number/letter/number. 69 and later date codes have 2 dots under the first number. Block casting numbers were generic... and you'll find the same number on different bore blocks in some cases. So don't count on that to much.

G.

If the engine is a 428 (and complete) there will be a a counterweight on the sleve behind the harmonic balancer. The 390 is internally balanced and will have sleve without the weight.

The 12th picture down on this site shows a picture of the sleve with the counterweight.

http://www.mustangandfords.com/techarticles/15999/

Originally Posted by Mike P

If the engine is a 428 (and complete) there will be a a counterweight on the sleve behind the harmonic balancer. The 390 is internally balanced and will have sleve without the weight.

The 12th picture down on this site shows a picture of the sleve with the counterweight.

http://www.mustangandfords.com/techarticles/15999/

Mike only the 428 SCJ used the balance sleeve or "cookie cutter" as some guys call it behind the harmonic balancer. The 428 and 428CJ's don't have that..stock from the factory anyway. The SCJ used heavier LeMans rods and Ford took the balance pad off the #7 crank counterweight on the IUA SCJ crank and put more weight on the nose with the balance sleeve. Not the best idea but it worked and was a low cost solution vs making another crank casting for the SCJ. If you put a std IU 428 or IUB CJ crank next to a IUA SCJ crank you'll see exactly what I mean. The link you posted also mentions this about the SCJ crank and balancer.

G.

I stand corrected, thanks.

No problem and that's a nice writeup you posted the link to. Good reading!!!

Happy Holidays!

G

Hi!

The block is at my friend's garage, after some days I will get it to home.

The cylinder heads: 08AE-H
Is it tell something?

The intake manifold is a two barrel type. Does it means it is a 390 with 265 HP?
I read all the 428 have 4 barrel intake manifold. And the other 390 has a four barrel. And the Intercetor tpye - like mine - has 2 barrel.

Thanks!

Is the 2 barrel intake a definite answer that it is a 390 cid engine?

On the intake no. It could be a 390 but also a 360. The 360 has the same bore block 4.05 as the 390 it just uses a shorter 3.50 stroke crank. In essence it's the same block between the 390 and 360. Just different cranks, pistons and rods. As far as the heads go the C8-H heads were very common to find and are pretty much standard FE heads. Same casting as the later D2-AA truck heads minus the induction hardened seats. C8's are a good head and with some work (port and bigger valves) can be a nice performing head. They were used on the 390,428,360 and a few others so they are not specific to a paticular engine. You'll need to dig into that pup a bit to see what you have.

G.

Thanks! Then it would be a 360 or a 390!
DannyW posted: 102.8 and 102.9 is the difference of the two engines(360,390)
I will check it and .. there will be light!

What headwork do you reccomend?

Well it depends what the end use is??? And what vehicle it's going in?? And the "B" word "budget"?? Are you doing a stock rebuild, street/strip, race only etc... If your going for max performance you'd want new heads. By the time you put bigger valves, port and polish, hardened seats, spring kit, guides etc...you'll be very close to a new set of Edelbrock aluminums. If these were say a set of rare heads or needed in a numbers matching situation then it'll be worth the while. It all boils down to what yer buildin!!

G.