Does Boring an Engine Add any HP?

[88GTMustang]

Like .030 ?

 

[proxses]

Not really. What it does is unshroud the valves so they can flow with less restriction. Most 5.0 heads don't really have this problem. So the biggest reason is to build an engine with a fresh bore and hone on your cylinders. This make for a clean rebuild.
The new modular engines see more of an increase because they do have a valve shouding problem.

 

[Sicarius428]

Probably about a 4hp difference.
Kevin

 

[88GTMustang]

so basically it dont do $hit for power?

 

[matm347]

Everything else the same, I would give 4-10 with most of the H/C/I combos.

 

[88stangmangt]

i would just hone it. if your looking for a re-build

 

[408stroker5.0]

Boring an engine add's Displacement and Compression, which in turn makes more power. So, technically yes it does add HP. Not a huge difference though, but enough to prove itself on the dyno.

 

[Michael Yount]

It adds displacement; not quite sure how it adds compression though. The main reason for boring is to true up the cylinder - returning it to perfectly round. This allows for better cylinder/ring seal so you get all the cylinder pressure you can with your breathing package. Over time, the nature of piston engines is to oval-out their cylinders; the .030" overbore cleans that up and returns the cylinder to round.

 

[iamarolltide]

do it ,I see no reason to build an engine and not do it right.
"there is no replacement for displacement"
I tend to agree with that

 

[88GTMustang]

well i got me a 2000 explorer block so i was just wondering about it cause me friend has a S10 with a 350 and keeps saying that he wants to bore it out 30 over and it has like 10k on it and was wondering why he was doing this

 

[88stangmangt]

bigger displacement

 

[90mustangGT]

As said before, it is just a procedure for making the cylinder perfectly round. Yes, it would unshrowd the valves some, and of course adding cid is good for power, but it's not worth tearing down the engine to do. Of course some class restricted races, every little bit makes all the difference. So they bore thiers way out to the limit of 310cid, about 4.060.

Not mentioned, but one bad thing about boring over a cylinder hole is it makes the walls thinner, so more prone to cracking.

 

[Michael Yount]

It occurs to me that boring your engine significantly won't increase HP much; but increasing your HP significantly will keep your car from being boring.

 

[SmockDoiley]

Tell your friend he's a freakin moron if he bores it. Anybody who bores an engine for horsepower needs to be shot in the face, especially a good engine with 10k on it. The reason to bore is like he said. Over time a cylinder loses round and the only way to get it back is to remove some metal by boring. The only people who should be boring are those who need to rebuild the engine because its bad, those in displacement limited race classes that need as much edge as possible, and those boosting that need a true round even better than the factory.

 

[noslow5_0]

It occurs to me that boring your engine significantly won't increase HP much; but increasing your HP significantly will keep your car from being boring.

hahhahaha.... thats funny

 

[Mach428]

The only diffrence you will probably note is a slight power curve change, over boring an engin will usually make it slightly stronger off the bottom.

 

[IndyBlk5.0]

That guys a moron, dont listen to him, if he only wants to bore it out, and not change the crank ect. to make a stroker, then he really is dumb on a 10k motor.

 

[SmockDoiley]

Like I said, freakin moron; shoot him in the face!!

 

[Michael Yount]

As a practical matter, any power increase attributable to a .030" overbore is statistically irrelevant.

Smock - you figure out your speedo?

 

[PURESTREET5006]

My block is a .060 which makes it a 310 and the only reason why is due to P/S class max is 311 cid and i have a 69302 block which is much thicker.....it's the whole combination that makes power not just this part or that part.