May sound like a dumb question, but how do you figure the cubic inches of a 5.4 V8? I've read the signature bylines of guys claiming everything from 329ci to 390! How so?

 

329 is correct.

Actually to be real geeky about it...the engine is 328.9 cu. inches and 5391 cc or 5.391 litres.

 

HI!... FORD rates it as 330ci, not 329. That's what it is rated at here in WINDSOR at the FORD ESSEX ENGINE plant where the 5.4's are built.

 

That's what Ford may say, but the math says otherwise. 1 in^3 = 16.387064 cm^3.

Using Logical's 5391 cm^3, you get 328.979 in^3. If you assume that the engine is actually and truly 5400 cm^3, then you get 329.528 in^3. So in reality Ford rounded up by about 9 cm^3 and or 1 in^3.

 

Looks like Ford has learned ricer math!

 

It ain't 390, that's for sure

 

Its a 330 my 4.6 is a 281.

 

5.7 = 346 cu.in. as in the LS1/LS6

 

You may be right that 5.4L is 329, but FORD is also right in saying 330 is 5.4L. It's just rounding.

 

First it was the radiators and now the engines are smaller. What's up with that?

 

I think some of the engineers at Ford have a "size" complex....

 

Oh God, here we go again... Does anybody remember all the discussion about this on the mailing list back about 3 years or so?

One Liter has 61.02545 cubic inches.

So, it would appear that the following is correct:

5.4L x 61.02545 = 329.53743 cu. in. So, you could call our engine a 330 cu. in. engine.

However, you can only call it a 330 if you're playing fast and loose with the math, scientifically speaking.

If you asked a person trained in science to convert 5.4L to cubic inches, they'd come out with 329.4 cu. in. because that person would have to deal with something called significant figures (sig fig). 5.4L has only one sig fig. Therefore, the math should be:

5.4L x 61.0 = 329.4 which when rounded out is 329 cu. in.

It would be a 330 c.i.d. engine if it was actually 5.40757L.

If anybody knows the bore and stroke to more than one sig fig, we can get a more accurate displacement.

BTW, L = l = liter Technically, I should be using lower case, but upper case in this font is easier to see. Sorry, just being a bit too **** retentive this morning.

 

Don't forget that the old 302 5.0L was really closer to a 4.9L. 5.0 just sounded better.

 

How do you know that 5.4 is not rounded? Don't convert it. What is the Bore and Stroke?

 

My numbers from above are the right numbers with very slight rounding of course ....it is not exactly 5.4L and Ford only refers to it as "330" so that nobody thinks they are talking about the old pushrod "329".

The engine is approximately 328.9 cu. inches and 5391 cc or 5.391 litres.

Bore and Stroke are approximately 90.2mm x 105.6 mm


90.2 diameter / 2 = 45.1 radius

45.1 squared = 2034.01
2034.01 x pi = 6390.03 square mm bore area

6393.03 x 105.6 stroke = 674787.26 cubic mm displacement per cyl

674787.26 x 8 cylinders= 5398298.08 cubic mm = 5.3983 liters

Obviously the 90.2 or the 105.6 figures are rounded slightly because the 5.391 comes from Ford literature.