Here are some bore and stroke figures on various ways to make a 427
block.......bore.....stroke
BB...............4.130 x 3.980
BB SOHC.....4.232 x 3.784
BB SHELBY..4.250 x 3.760
SB W...........4.030 x 4.170
as you attempt to increase the stroke of a SB engine, you make the piston travel a longer and longer distance. Toivo made a great point above where he said that you are using a shorter piston that can rock in the bore and lead to ring land issues. The other problem that you can rub into is the side loading the cylinder wall to a greater degree.
I do not think you can rev a SB stroker to the same extent of a BB stroker since piston speed is a function of stroke. Take a SB 427 at 6000 rpm and the pistons is travelling 4,170 feet/min, where a shelby aluminum BB 427 is travelling 3,760 feet/min. Therefore, you can rev an engine with less stroke higher due to piston speed.
http://www.prestage.com/carmath/calc_pistonspeed.asp
Stroker engines are very good at creating torque due to the leverage of the long stroke. These engines often resemble this on the dyno
The majority of performance car owners like the feel of this style engine for street use. It pulls like a freight train from 1000rpm. Racer's generally do not like this curve for the very same reason "it pulls like a freight train from 1000 rpm." On the track, most driving is in higher rpm ranges and torque in the 1000 - 3000 range can become almost useless. For tractor pulling, this is an outstanding curve as well
hope this info is useful
Andy
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