Pro-M Racing Bore and Stroke Guide


Chevrolet - Small Block

CID

BORE

STROKE

283 3.875 3.000
302 4.000 3.000
305 3.736 3.480
327 4.000 3.250
350 4.000 3.480
383 4.030 3.800
400 4.125 3.750
427 4.125 4.000

Chevrolet - Big Block

CID

BORE

STROKE

396 4.096 3.760
402 4.125 3.760
427 4.250 3.760
454 4.250 4.000
502 4.466 4.000
572 Tall Deck 4.560 4.375

Ford

CID

BORE

STROKE

260 3.800 2.870
289 4.000 2.870
302 4.000 3.000
306 4.030 3.000
331 4.030 3.250
347 4.030 3.400
351W 4.000 3.500
351C 4.000 3.500
351M 4.000 3.500
392W 4.000 3.900
393W 4.030 3.850
400M 4.000 4.000
408W 4.030 4.000
410W 4.040 4.000
427W 4.125 4.000
427FE 4.230 3.780
428FE 4.130 3.980
429 4.360 3.590
460 4.360 3.850
502 4.390 4.150
521 4.390 4.300

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