5.9 bored .30 over?

[19Ram150098]

When i bought my truck (98 ram 1500 5.9L) the owner said the engine was bored .30 over. Could anyone explain to me what exactly that means? Like does it have bigger pistons? and is it no longer a 360? i know its a stupid question, i was just curious

 

[SYKRAMMAN]

When i bought my truck (98 ram 1500 5.9L) the owner said the engine was bored .30 over. Could anyone explain to me what exactly that means? Like does it have bigger pistons? and is it no longer a 360? i know its a stupid question, i was just curious

Yes, the engine bore was made larger probably because of earlier damage, so the pistons are a little bigger. No, you no longer have a 360, you have a 366 now. Exact is 365.299 ci.

 

[19Ram150098]

ok, thank you!

 

[rrb6699]

I thought the engine block was still 360 cubic inches. The only thing you're changing is the bar of the Pistons which changes the compression I would think but I don't see how it increases the volume of the block

 

[crash68]

I thought the engine block was still 360 cubic inches. The only thing you're changing is the bar of the Pistons which changes the compression I would think but I don't see how it increases the volume of the block

360 cubic inches is the amount of volume of all eight cylinders at there original bore diameter and length. If you increase the bore diameter (like when cylinders are bored .030 over) or you change the length of the cylinder(stroking), then the displacement is larger.
Usually an engine once modified is referred to as it's original displacement (such as a 360, then state it's bored over) to avoid confusion of which block you have.

 

[Gr8bawana]

I thought the engine block was still 360 cubic inches. The only thing you're changing is the bar of the Pistons which changes the compression I would think but I don't see how it increases the volume of the block

You obviously know absolutely nothing about engines.
Once you increase the bore of the cylinders you have increased the size if them by .30 or .40 or even .60 on some engines. So you end up with more cubic inches.

 

[rrb6699]

I'm asking because although I have rebuilt several engines before, I never bored any out. and I don't know everything or much, but, I can take one apart and put it together with new parts. milled heads and a high riser manifold or two actually on a boat.

so if you want to confirm what I have to still guess from your reply, it increases the hollow volume of the engine block. even though that could have started as a 318 engine.

 

[Gr8bawana]

I'm asking because although I have rebuilt several engines before, I never bored any out. and I don't know everything or much, but, I can take one apart and put it together with new parts. milled heads and a high riser manifold or two actually on a boat.

so if you want to confirm what I have to still guess from your reply, it increases the hollow volume of the engine block. even though that could have started as a 318 engine.

Correct.

 

[gofishn]

I'm asking because although I have rebuilt several engines before, I never bored any out. and I don't know everything or much, but, I can take one apart and put it together with new parts. milled heads and a high riser manifold or two actually on a boat.

so if you want to confirm what I have to still guess from your reply, it increases the hollow volume of the engine block. even though that could have started as a 318 engine.

Yes. The engine is still a 360 engine block. or , in your example, a 318. however, since the engine displacement has been increased, due to a larger boring, during the rebuild, than the original block was bored, it is now a 366 or whatever.

for the sake of simplification, everyone still calls it what is once was, 31, 360, 440 whatever, then add bored .30 over or whatever the bore amount happens to be.

NOTE: some engine blocks take slight boring very well with no real negative effects. others do not.

I, personally, have never been a fan of "boring" an engine and would sooner get more power via another source.
Though as mentioned previously, if you want to re-use a block, sometimes there simply is no other option than to bore it out, slightly larger, due to cylinder wall damage.
And ,no, I do not want to talk about sleeveing,. if they even do that anymore.
Something else I was never a fan of.

 

[dapepper9]

Yes. The engine is still a 360 engine block. or , in your example, a 318. however, since the engine displacement has been increased, due to a larger boring, during the rebuild, than the original block was bored, it is now a 366 or whatever.

for the sake of simplification, everyone still calls it what is once was, 31, 360, 440 whatever, then add bored .30 over or whatever the bore amount happens to be.

NOTE: some engine blocks take slight boring very well with no real negative effects. others do not.

I, personally, have never been a fan of "boring" an engine and would sooner get more power via another source.
Though as mentioned previously, if you want to re-use a block, sometimes there simply is no other option than to bore it out, slightly larger, due to cylinder wall damage.
And ,no, I do not want to talk about sleeveing,. if they even do that anymore.
Something else I was never a fan of.

Sleeves are more durable and stronger when done right. And are required in anything with an aluminum block.