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I found this 351 Site. and wrote this letter. People were talking about doing a 351 C stroker. Then a 400 "C" Read on. Am I right? The last Question is at the end.

Old Post in Response to a stroker Question:

To the best of my knowledge the Aussie 2v Combustion chamber is 56cc. Might wanna figure that out too. Also, I have thought about this too in the past...STROKING A 4V CLEVELAND (I know yours is a 2v, and will end up worse off then the 4v) WHAT POWER THAT WOULD GIVE!!! But in Reality, doing it RELATIVELY cheap, running pump gas it just does not seem like it is going to happen. You are getting 11:1 Compression with a 3.5" Stroke. when you put an extra .5" of stroke in, what will that do to the compression ratio? Couple that with the EVEN SMALLER chambers of the aussie 2vs, and you have a HIGH HIGH HIGH compression ratio. The only way to compensate this would be a dished piston. Now you are back to a custom type of piston. Hope this helped, or might have cleared something up.
If I am wrong BY ALL MEANS CORRECT ME, IF I COULD GO TO A 396, I WOULD LOVE TO DO IT!!

Jeff Given


Ok, I made this post about the 351 C with a stroker in it. Now here is the prpose of this post.

Background info:
I go to FORDMUSCLE.com GREAT SITE. This has came up a lot there, and I am passing on the info I got from there to here...

First of all, the motor mounts are quite a bit differant. So putting the motor in anything that did not come with it is most certainly going to have to be fabricated.

The deck height of the 400 is a whole hell of a lot taller (relatively speaking) 10.297 to compensate for the extra stroke when compared to the 351C 9.206. When you put on the small chamber heads of the DOAE heads, and put an extra .5" of stroke in the motor, this will make the compression high. (if you mill the deck down) I would not know the Compression, but would guess it would probably be 13:1 or somewhere close.

You can try to say, well we will avoid that, and just not mill the deck. Well that will keep the compression down yes. Now, I have heard that the QUENCH of the head only works at its best when the piston is closest to the Combustion chamber. By working best, I mean it "Extinguishes" the flame, and "cools" the chamber Denoting the detonation, or pinging. So if you leave the deck height the same, you lower the Compression, (lets just say 10:1) Although it may not be that high, and it probably wont be, you are more likely to ping. Why? The Piston is not as close to the chamber.

Needless to say, Flat top pistons, on a 351 C block, you get roughly 11:1 Compression with DOAE heads (closed chamber). The stroke is perfect (gets the piston close to the head) to allow for the QUENCH to work properly, and efficiently. put the heads on the 400, and your pistons are not as close to the heads. (1" more deck height, .5" more stroke) Mill it, and you have a too a high compression ratio.

I do not know if you can go above the 11:1 compression ratio, and run on 91 Octane. (I do with 11:1 and 91 Chevron) But the risk of going to a higher compression could be a 5000 $ screw up, that I dont want to take...Do you?

ok, now, is this all right, partially correct? not at all? Thanks a lot!

Okay assumming I am right with my madness...if you only mill the deck height .5", the deck height is only approx. .5" taller. the stroke to deack height ratio is the same...Correct? So it seems that you could get away by doing it this way.??

Anyways, I have an unlimited access to a wrecking yard, and would think the project would be a lot of fun...but costly, and I dont have the money...but someday, or if dad wanted to help, that would be nice. Thanks a lot guys!

Jeff Given
 

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The pistons in the 400 are dimensionally the same as good old 351 C pistons, with the exception that the 351's pistons have a smaller piston pin diameter. No problem just have the rods bushed. You could even have floating rods with pin locks for just a little more $$. You can buy dished pistons for the cleveland. They're not cheap, but they are available. Compression will still be high even with the dished pistons. I'd just run 4V open chambered heads. They flow better than closed 4V heads (less shrouding) and they have the same chambers as the standard 400 heads, so detonation won't be a problem. you could even mill the block (or the heads or both) for extra compression. With the right camming and proper intake and exhaust, you would have a 475+ hp motor. Thats no joke. Big problem: custom headers will ruin all the low buck fun. You could run sanderson shorties. Sanderson makes shortie headers for freakin everything check it out.
 
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