Crankshaft vs. cubic inches clarification

[toofastforyou]

I'm a little confused as to which crankshaft will give how many cubic inches… I know this is in relation with the bore of the block, but what stroke does it takes to make a 231, a 252, a 271, etc… Does a 4.1 L = 271 cu. in. ?…or is it a 252 ?

Claude.

 

[ScottHeidinger]

4.1 is 252 in stock form


Sent from my iPhone using Tapatalk

 

[DavzGN]

Bore x Bore x Stroke x 4.71 will get you pretty close to correct Cubic inches for a v6.

3.8 bore with 3.4 stroke comes out to 231 cu. in.

Sent from my XT1650 using Tapatalk

 

[toofastforyou]

Ok thanks guys but… then what does it takes to get a 271 (or is it a 274) ?

Claude.

 

[DavzGN]

4.0 bore with 3.6 stroke would be 271

Sent from my XT1650 using Tapatalk

 

[rag231]

You probably wont find a 3.6 stroke crank but a 3.58 or 3.59 will give you 270 cu. in.

 

[toofastforyou]

Ok so if I understand correctly,

3.8 bore x 3.4 stroke = 231 cu. in.
4.0 bore x 3.4 stroke = 252 cu. in.
4.0 bore x 3.6 stroke = 270 cu. in.

Right?

Claude.

 

[ScottHeidinger]

Standard 4.1 is 3.965 bore x 3.4 stroke = 252 CI
Is there a certain cubic inch you are aiming for? I think the standard aftermarket stroker cranks are 3.625 and most bore out the 4.1 block to 4" since its a more common size for Pistons. With a 4.1 block bored to 4" and 3.625" stroke it should be around 274 cubic inches.


Sent from my iPhone using Tapatalk

 

[toofastforyou]

Standard 4.1 is 3.965 bore x 3.4 stroke = 252 CI
Is there a certain cubic inch you are aiming for? I think the standard aftermarket stroker cranks are 3.625 and most bore out the 4.1 block to 4" since its a more common size for Pistons. With a 4.1 block bored to 4" and 3.625" stroke it should be around 274 cubic inches.


Sent from my iPhone using Tapatalk

I am aiming for 274 cu. in. Right now,I already have the on-center block (#153), rods, pistons but I'm missing the crankshaft. The one I had had a shorter stroke (although it was ok but I did not have the cubic inches I thought I had !) but now I'm looking for a 3.62 stroke crank to replace it...

 

[dank GN]

I just finished my 281 CID

 

[toofastforyou]

I just finished my 281 CID
wow!…Nice!

How did you achieve 281 cu. in. ?

Claude.

 

[dank GN]

How did you achieve 281 cu. in. ?

Claude.

4.061 bore
3.625 stroke
6.500 rod

 

[~JM~]

http://www.ajdesigner.com/phpengine/engine_equations_cubic_inch_displacement_b.php

http://performancetrends.com/Calculators/Engine-Displacement/Engine-Displacement.php

 

[~JM~]

I just finished my 281 CID

 

[VtheGNMan]

I just finished my 281 CID View attachment 304000

Holy mother of..........

 

[dank GN]

Thanks guys I actully just fired it today . Spec
281 cid
4.061 bore , 3,625 billet crank, 6.500 on center rods, ported TA SE , 1.75 rockers, 230/230 solid roller , CT43 6871 triple ball bearing billet wheel,

 

[~JM~]

Dank just dropped the M.O.A.B.

 

[David Husek]

I'm a little confused as to which crankshaft will give how many cubic inches… I know this is in relation with the bore of the block, but what stroke does it takes to make a 231, a 252, a 271, etc… Does a 4.1 L = 271 cu. in. ?…or is it a 252 ?

Claude.

The most popular crank is 3 5/8" or 3.625". A connecting rod is not relevant when calculating cubic inch.

I supplied a list as to help you get an understanding how bore and stroke relates to cubic inch. All figures are accurate to within .5 cubic inch in table below.

3.8L = 3.8" bore
4.1L = 3.965" bore

231 = 3.4" stroke x 3.8" bore
234 = 3.4" stroke x 3.820" bore
235 = 3.4" stroke x 3.830" bore
236 = 3.4" stroke x 3.840" bore

247 = 3.625" stroke x 3.8" bore
249 = 3.625" stroke x 3.820" bore
250 = 3.625 stroke x 3.830" bore
252 = 3.625" stroke x 3.840" bore

252 = 3.4" stroke x 3.965" bore
256 = 3.4" stroke x 4.0" bore
257 = 3.4" stroke x 4.010" bore
259 = 3.4" stroke x 4.020" bore
260 = 3.4" stroke x 4.030" bore
261 = 3.4" stroke x 4.040" bore
263 = 3.4" stroke x 4.050" bore
264 = 3.4" stroke x 4.060" bore

269 = 3.625" stroke x 3.9625" bore
273 = 3.625" stroke x 4.0" bore
274 = 3.625" stroke x 4.005" bore
275 = 3.625' stroke x 4.010" bore
276 = 3.625" stroke x 4.020" bore
277 = 3.625" stroke x 4.030" bore
279 = 3.625 stroke x 4.040" bore
280 = 3.625" stroke x 4.050" bore
281 = 3.625" stroke x 4.060" stroke

 

[toofastforyou]

Thank you David! That's the best explanation I could ask for.

Claude.

 

[chris kirk]

The most popular crank is 3 5/8" or 3.625". A connecting rod is not relevant when calculating cubic inch.

I supplied a list as to help you get an understanding how bore and stroke relates to cubic inch. All figures are accurate to within .5 cubic inch in table below.

3.8L = 3.8" bore
4.1L = 3.965" bore

231 = 3.4" stroke x 3.8" bore
234 = 3.4" stroke x 3.820" bore
235 = 3.4" stroke x 3.830" bore
236 = 3.4" stroke x 3.840" bore

247 = 3.625" stroke x 3.8" bore
249 = 3.625" stroke x 3.820" bore
250 = 3.625 stroke x 3.830" bore
252 = 3.625" stroke x 3.840" bore

252 = 3.4" stroke x 3.965" bore
256 = 3.4" stroke x 4.0" bore
257 = 3.4" stroke x 4.010" bore
259 = 3.4" stroke x 4.020" bore
260 = 3.4" stroke x 4.030" bore
261 = 3.4" stroke x 4.040" bore
263 = 3.4" stroke x 4.050" bore
264 = 3.4" stroke x 4.060" bore

269 = 3.625" stroke x 3.9625" bore
273 = 3.625" stroke x 4.0" bore
274 = 3.625" stroke x 4.005" bore
275 = 3.625' stroke x 4.010" bore
276 = 3.625" stroke x 4.020" bore
277 = 3.625" stroke x 4.030" bore
279 = 3.625 stroke x 4.040" bore
280 = 3.625" stroke x 4.050" bore
281 = 3.625" stroke x 4.060" stroke

Nice!!! This is the kind of info the forum should be used for! Great job, David.....

Sadly though, much of what's on here now is; what if I replace the bolt in my antenna will my car not be original anymore...... Will it decrease the value..... I'm really worried...... What if someone notices.....

It's no wonder why they complain about bandwidth sometimes, I would too!