Thread: Cubic Inches vs Liters

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Anybody besides me ever wish the whole liter thing would go away?

Back in the good old days (cubic inches) a 345 inch motor was a 345. a 350 was a 350 and a 351 a 351. Now there all 5.7 Liter.


Way too much time on my hands today.

Yep, liters X 61 equals cubic inches.

Cubic Inches = Engine Size
Liters = Soda Pop Size.



JMHO


AFLAC

Well as far as I know it is written on every oil container somewhere that 1quart=946 ml or 946cc. To all intents and purposes 1 ml = 1 cc = 1 cu. cm. although that is really only true at 4 degrees C since only at that that temperature does 1 ml of water = 1 gram of mass and the density of water on which the liter is based does vary slightly with temperature. So basically a liter is roughly equal to a quart. The way I remember which is bigger is to recall the picture that ran in pulp magazines for over 20 years for the Charles Atlas body building advertisement in which a muscular guy kicks sand on a skinny guy at the beach with his girlfriend and I recall "A leader is bigger than a squirt!" so OBVIOUSLY (!) a Liter is bigger than a Quart! (Sometimes it takes silly rhymes to remember this stuff, but it works!) So since 1 inch = 2.54 cm, 1 cu. in. = (2.54x2.54x2.54) cc = 16.387064 cc. Thus a 2.0 L Pinto 4 cyl is about 122.05 cu. in. and conversely a 355 cu. in. SBC would be (355 x 16.3870 )= 5817.385 cc or 5.817 L. I know it's annoying to convert to metric values but the advantage gained is that the metrics are all related by powers of 10 and of course that is helpful since we can then use our fingers and toes to count (Ann Bolynn had 11 fingers, however so there are exceptions!). If you really want to get confused check out the British Imperial Gallon versus the U. S. Gallon or try to work on a British sports car where the measurements are not metric but may not all be SAE either! That is why I have several "adjustable" cresent wrenches! Hey how about those side-draft carbs, aren't they fun!

Don Shillady
Retired Scientist/teen rodder

DennyW, maybe you can appreciate that the reason my figure is not as svelte as it was when I was 18 is due to the fact that when I sent in my quarter for the Charles Atlas book it never came and I am still waiting! While I am on a British car memory lane how about the monocoque floor pan with a driveshaft tunnel that only permitted a "blind" insertion of the drive shaft into the back of the transmission! I wasted three hours on that one before calling a foreign car agency and they had a good laugh. It seems you have to wrap the front universal joint with a lot of masking tape to make the driveshaft into a rigid "spear" which will then slide onto the trans splines. When you start up the car the tape flies off but who cares!

Don Shillady
Retired Scientist/teen rodder

Yep, duct tape on the socket u-joint when reaching bellhousing bolts.

Good tips to know from the Pros! At the moment I am worrying over the last things I have to do to the Brookville frame (battery box, headers, mufflers and leaks in brake line fittings before I put the 'glass body on the frame) BUT it does help to wonder how to get access to things like the master cylinder and the battery after the body is on. On another thread C9x has pictures (Questions about Model A seat) of his under pinnings and man oh man it is all very tight on a Deuce frame so I am scratching my head on the '29 frame, but it helps to know that a lot of folks have done this before. Back to the liters, you can see from my example of the Pinto 2.0 L engine at 122.05 cu in that Tech1's easy conversion of 61 cu in/liter is good enough for estimates. Another conversion that is good to know for gas tank dimensions is that (4x946 cc)= 3784 cc/U.S. gallon so that if you measure a gas tank in inches as length x width x depth to get cubic inches you can divide the 16.387 cc/cu in into the 3784 cc/gallon to get (3784/16.387) = 230.914 cu in for one gallon. The guys who design gas tanks say to just use 231 cu in per gallon. I try to remember this as the size of the Buick V6, so every two revolutions the V6 gulps in a gallon of fuel-air mixture. Thanks for the floppy-universal-socket-tape-fix for the socket wrench!

Don Shillady
Retired Scientist/teen rodder

Mike check out this converter at http://www.csgnetwork.com/cubicinchlitercvt.html For the dumb metrics to know the difference between 5.7 liter as the 348 and the 352 you need to go out to like 4 places in cubic centimeters and that's just bullcrap.

It's not the point of knowing how to do the conversions, I can do that (but thanks everybody). I guess it's all this political correctivness that started around 66 When Ford labeled some 427 galaxies as 7 Liters as an advertising gimick.....

This was followed shortly after with the government deciding that Highway speeds should be in KPH instead of MPH so we would conform with the rest of the world. Anyone remember the dual speed limit signs you sometimes saw in the 70s along with the dual reading speedometers? As I remember this was done to help poeople with the transition from MPH to KPH...that worked really well .

I guess the world moves on, but it doesn't mean I have to go with it, I still believe real engines are measured in cubic inces

I agree with MikeP's point completely - I think it actually serves to dumb down Americans just a little more. But its great for 99% of the consumers. Its simply orders of magnitude rather than exact figures.

But orders of magnitude don't work well for exact calculations.
They are however great for comparisons.

Its all about resolution vs. ease of comprehension.

Anyone remember the dual speed limit signs you sometimes saw in the 70s along with the dual reading speedometers?

Thats my analogy (like Don's "A leader is bigger than a squirt!") for approx. MPH to KPH conversion. 80 KPH sat right over (well real close to) 50 MPH on the speedo.

So - a kilometer is approx. 5/8ths of a mile!

For the dumb metrics to know the difference between 5.7 liter as the 348 and the 352 you need to go out to like 4 places . . .

Exactly right - but a 351 is actually a ~351.9 - so rounding occurs everywhere. There is also a 352 (another 351.9 I think) - someone else will have to remind me as to what that was about.

OK -

I think I'll go pickup a 1.892 quart coke - this discussion has made me thirsty.

Maybe a 1.6555 quart bottle of bourbon too! AKA 1.75 liter or for me and most of the people I hang with - 1/2 gallon.





Bert

Another way to hold the nut in the socket is to pack the socket with wheel bearing grease. Maybe having 11 fingers would work also.

Ron

I had a guy come up to me Sunday as I was getting in the car and start going on about how the "cubes" were on the side of the car again. At first I wasn't getting his drift, but then it dawned on me. He meant the 281 emblem. Then he continued on about how he wrote a letter to Ford a few years ago telling that if they wanted to sell cars to "baby boomers" they'd better get back to using cubic inch emblems instead of those @%*# liter things. He was pretty wrapped around the axle about it!

Well my point is the fact that when some goof begins with "...a 4.1 liter Wazoo V-6..." you can convert to what it really is in normal American size. 61 cubic inches = 1 liter = 1,000 cubic centimeters. 4 x 61= 244 and the .1 = 6 cubic inches- total 250 CID. Quick, how big is 2.3 liters in cubic inches?

Using CID is more precise to tell that a 348 ain't a 351 even if both are 5.7 liter. When it gets to "is it a 5.70 or 5.77 liter?" it's getting freaky deaky. For exactness you'd have to be breaking crap down to cubic centimeters where displacement would look like 5,751 cc. Bullhockey!!!

A "348CID" engine puts ONE picture in our heads. A "5.7 liter" is ambigious and does not specify THE engine but rather a groups of engine sized generally the same yet they're way different.

The 7 liter business began in the 60s when Henry Ford was pissed after Enzo Ferrari decided not to sell out to Ford. Ford committed to building a racing program with the Ford GT-40s and Corbas vowing to beat Ferrari at their forte- prototype GT car racing. The rest is history and that's when the liter bullcrap began in automotive namaclature on Galaxies with 427s.

Just think the Beach Boys couldda been singing "she's real fine, my six point seven..."

Anybody, especially on these boards, that describes his "4.6 engine" ought to be strung up.

Anybody, especially on these boards, that describes his "4.6 engine" ought to be strung up.

I agree - but - I bought a 4.7 Dodge truck - how do I determine exactly what it really is?

Everything I read says 287ci (286.811578 = 4.7x61.02374).

But - thats assuming its REALLY a 4.7

Maybe its really a 4.7358618137793586561557846175931 L

Thats 289 exactly (using 61.02374 ci/L) -

Bert

While we are having fun, let me recall another adventure with metric units in the SAE world. I use metric units every day in Chemistry so when I actually bought a brand new 1973 Vega two door wagon I thought why not get a few frills so I paid an extra $180 for the "Rally Pack" option. When I took delivery of the new Vega (a very nice Fisher body style, but let's not talk about the aluminum cylinder walls) I found the "Rally Pack" consisted of a thin decal pin stripe on the sides AND best of all, a DECAL on the speedometer showing Kph alongside mph! WOW, a $180 decal! Anyway from that decal I figured that 1 mile = 1.6093 kilometers, so 100 Kph is about 62.1 mph, and yes a kilometer is smaller than mile. Regarding the case of 11 fingers, there is a recent TV ad where a guy has 6 fingers on each hand for a total of 12 fingers and supposedly he gets more office work done. Anyway it is clear that there is great resistance to metric units in the U.S. and my favorite suggestion is to keep all the measurements actually the same as the SAE sizes and just change the blueprints to read the sizes in metric! The only sanity to it at all is that as far as I know the metric folks do agree that 1.0000000 inch = 2.54 cm with no further decimals needed. The same sort of problem occurs in science where NIST/NBS routinely refines the numerical values of basic physical constants about every 10 years using a least-squares fit of all the constants to all known physical data. In Theoretical Chemistry this caused severe problems back in the 1930-1940 era but has been solved by defining every physical unit to be "1" in terms of the formulas so that as new values were updated only the algebraic formulas were needed to relate to the real world and this has worked out very well using what are called "atomic units" so modern 2005 calculations can be directly compared to calculations from the 1930s even though the values of the constants have been updated several times. Not to offend any of our friends in France (Viva LaFayete!) but you may recall that the meter was supposed to be exactly (1/10,000) of the circumference of the Earth at the equator, cut into a piece of metal kept in a temperature controlled case in Paris, BUT (Oh Oh!) they didn't have the right value for the Earth's circumference, SOOOO the meter is totally arbitrary based on an error! Too late now because the meter has been redefined in terms of laser wavelengths and adopted as an international standard. So the king's "foot" = 12 inches and maybe 1" is the king's thumb knuckle and maybe the Biblical Cubit is the length of an average forearm but you got to start somewhere and now with lasers length has been refined to many sig. figures. The worst cases are the need of Chemical Engineers to carry around pocket tables of conversion factors, but probably the several systems of units in electrical measurements are the most difficult but I like "atomic Units" which by the way define 1 bohr =0.529177 x 10^-8 cm (this value is presently under revision but the 0.5291 part is pretty definite) so there we are back to metrics, but in "atomic units" all the units are "1" times the formula for whatever is being measured, I like that system but for cars I guess all I need is 1.6093 Km/mile, 946 cc/qt. and 61.02374409 cu in/L or roughly 61.024 cu in./L.

Don Shillady
Retired Scientist/teen rodder