What are bores and stroker kits? what is displacement?

Question

I hear they make the displacement better! However what are they? And I'm talking about performance bores and stroker kits.

Answer 1

a stroker kit is the crankshaft ,rods & nearly always new pistons. it increases the pistons travel up & down so increases the size/displacement ( more cubic inches or centimeters) of the engine. since your going to replace the pistons anyway & big ones cost the same as smaller ones most people bore the cylinders out bigger & get another displacement increase that way . bigger engines will have more power than smaller ones, if everything else is equal

Answer 2

The bore is the diameter of each cylinder. The stroke is the distance the piston moves up and down in the cylinder. Generally, a larger bore will give you more horsepower (higher speed) and a longer stroke gives you more torque (off-the-line power) Both would be a lot of work; to bore an engine out, you have to have each cylinder machined out, except for air-cooled VWs, where you just buy new cylinders. To stroke the engine, you need a different crankshaft, pistons and connecting rods. If you do them both, do them at the same time.
Displacement, BTW, is the total area contained in the bore and stroke. The formula is: Pi x radius[squared] x stroke x number of cylinders. A V8 with a 4-inch bore and a 3-inch stroke gives you around 302 cubic inches

Answer 3

the bore, or diameter of the cylinder can be honed or "bored" out to a larger size, this allows more fuel and air to be burned, thus increasing horsepower ( and fuel use!!) Displacement is the amount of fuel air used in one stroke of the pistoon in the cylinder. At least that's the simplest way of putting it. The kits contain everything from a new cylinder head (in some cases,)alarger piston and rings too, along with a few other needed parts. Others require you to bore out the old cylinder. Again, this is just a simplified answer.

Answer 4

a bore and stroke kit gives you larger pistions, (in diameter) and the match rings to go with those same pistons to allow a machine shop to increase size of the bores in the engine block thru a machining process... this takes care of increasing bore size...

now on to stroke... to increase the length of the travel of the piston up and down or side to side in the bores (VW, corvairs and subarus) this is accomplished in one of 2 ways

#1) the replacement of the original connecting rods with longer ones

or

#2) a specially machined crankshaft which has had the rod journals welded on and reground to increase the offset of how far the rod journal moves the connecting rod and piston in the cylinder bore...

these add cubic inches/cubic litres and also increase the horse power output of a engine...

Walt