Class Rules

[Jix008]

I have a question for u builders, i rules state you may change rod journals to fit a chevy 2.0 rod size most of the time is a 5.7. So my question is if you up the bore to say a .30 you would end up with a 2340 also there is a no stroke rule on the crank. So does the head set up in any way effect this pound per cc rule. How is it some one can have say 2368cc if there is no stroking the crank.
I am not a engine builder but it seems like to me the 8 shows a stroked crank right. Or is there more that has to be looked at to come to the numbers on the hood.

[chrisw21_2000]

Bore and stroke are the only things that change the displacement. Boring bigger without stroking the crank will increase displacement and a longer stroke crank will also increase it. Rod length and anything to do with the head won't change it.

[dynoman14]

Other folks are running a bigger bore than you. How big will rules let you go?
You should also consider putting manifold studs in the head so yo can deep cut the head. I usually cut about 1/3 of the stud off. Your other post talks about a ported head, is it the same engine? One of the keys to making the head flow on the engine is positioning the head on the block.
Do yo have an engine builder doing your build?

[Jix008]

I do have a very good engine builder one of the best for my type of class. On bore there is no rule, but i would seem to think to get anything but a zero on your pound per cc like 2368 the 8 comes from stroking the rod journal with is part of the crank which say no stroking the crank in are rules and must be stock stroke. But you can use a 2" rod journal but the rod journal centerline must stay stock if during the turning of the rod journal u off set it and move the centerline to put a little stroke in it then there for haven't you just cheated by moving the centerline of the rod journal.

[Headhunter]

They may be offset grinding the crank to get a little bit more stroke lenght.

[drtlvr]

I have a question for u builders, i rules state you may change rod journals to fit a chevy 2.0 rod size most of the time is a 5.7. So my question is if you up the bore to say a .30 you would end up with a 2340 also there is a no stroke rule on the crank. So does the head set up in any way effect this pound per cc rule. How is it some one can have say 2368cc if there is no stroking the crank.
I am not a engine builder but it seems like to me the 8 shows a stroked crank right. Or is there more that has to be looked at to come to the numbers on the hood.

There is a formula on here somewhere that figures the cc's from cubic inches. From what I recall, a 2300 ford bored 30 is actually a little bigger than 2330. So if someone is claiming a 2368, that may very well be a .060 2300. Either way, you'll never tell the difference in 8cc's.

cubic inches to cc's is for ex. (.030 2300 divided by .0610237) 142.557 / .0610237
.7854 x bore x bore x stroke x 4 = cubic inches

[84Dave]

Cubic Inches to Cubic Centimeters? Cubic Inches x 16.387 = CC's. -Dave-

[drtlvr]

Yep, that's another way.

[that dude]

this is what i figured long ago uisng cubic inches (bore * stroke)
<<<<<the B & S numbers came from a google search that lead to a info page about strokes and displacements for the ford "lima" engine

Then converting to cc (as dave said, and cheating using an online converter)..

3.780 * 3.126 = 140.377ci = 2300.367cc
3.810 * 3.126 = 142.615ci = 2337.041cc (+.030)
3.820 * 3.126 = 143.364ci = 2349.315cc (+.040)

3.780 * 3.401 = 152.727ci = 2502.747cc
3.810 * 3.401 = 155.161ci = 2542.633cc
3.820 * 3.401 = 155.976ci = 2555.989cc

[Old Rob]

The process is to find the area of a circle
Pi x the radius squared.
next, the volume of a cylinder,
Area times height.
For an engine multiply this by the number of cylinders.

Pi x half of bore squared x height x number of cylinders.

The formula process is the same for metric or domestic measurements. It will not work with Wentworh diminsions.

As 22Dodge would say "it's just elementary school math."