Engine bore and stroker?

Question

.030 over bore..is that good? what is a great bore? and what does it mean when are car has a stroker

Answer 1

A 350 cubic inch motor bored .030 will displace approximately 355 cubic inches once bored.... a stroked engine will  require special pistons with the pins moved upwards in the piston due to the longer stroke, thus not hitting the cylinder heads.....Chev 383 strokers are nice motors and make lots of HP with the proper Cam, Carb, Intake, and Exhaust...

Answer 2

a stroker is when you put a crankshaft with a longer stroke in an engine. it increases displacement.

the most common example of this is a chevy 383 stroker.

0.030 overbore means the bore is 30/1000 of an inch larger than stock, this also increases displacement but not by much.

when the engine was rebuilt the cylinder bores were probably out of round and had to be machined to make them round again. it is very common. any engine with any amount of wear will probably have to be overbored when it is rebuilt

Answer 3

.030 over bore is a standard practice at a machine shop because replacement pistons are easier to get. And the above explination for stroker is right. A 400 cid crank in a 350 cid with standard 5.7 inch rods makes it a 383. Strokers make good mid to high rpm power. The old 283 cid with a 307 cid crank  which made a 302 chevy  made wicked horsepower and rpms

Answer 4

Above got you covered, I just try to tell more not looking for a best answer.

Over time the piston wear the cylinder to the point the ring lose compression. Regular rings no long work as they can not expand to the Diameter of the cylinder. They make over size rings to compensate OR people will bore the cylinder for oversize pistons (Which I think is best). Though it more expensive as you have to buy a new piston for the new bore. BUT!!! Regardless of what people may say. IF, you go to a good machine shop you will learn you only need to bore the cylinder that needs bored!!!! YES, many will say this not so and that OK they can buy 8 new pistons instead of 1 or 2. The bore not that big a deal for regular driving. The over size pistons will be marked on top what they are; .010, .020, .030 I think you can go .040, but, I would make that the limit and ask my machinist.

The Stroker mentioned is mainly a longer piston rod. Chevy (s) can be changed from a 350 to a 383 (Stroke not Bore) as mentioned above by changing the length of piston travel which is changing rod length on the piston. BUT, sometimes when this is done you need to machine clearance to compensate for the longer stroke of the piston. So, again, talk with a machinist.

I have rebuilt many engines and I have a machinist that Boil my block, shave heads, bore cylinders etc.

If, you going to start modifying  or rebuilding engines you need to find you a "GREAT" machinist. NOT Auto-Zone or American Engine Rebuilders or whatever. A good machinist know his Sh*t and is well worth your time and money. Mine can tell me everything about an engine just from the numbers on the block. And can make what not made anymore, if, it something old.