livelyjay

I'm going to be purchasing a B16 engine in the near future and I wonder what people mean when they talk about "building" up an engine. What exactly can you do besides change out some of the internals like the cams and valve springs? What does it mean to re-sleeve the cylinders and how is it done? What could be done to the B16 to bring up its torque output?

1stGenCRXer

A "built" engine is normally one that has just had the compression ratio, or displacement increased, along with making it more efficient or reliable for high RPMs or boost. There are other little things that can be done, but that's the very basic jist of it.

MrFatbooty

A "built" motor is one where the large majority of the internal parts have been replaced or upgraded. Pistons, rods, head porting, are a couple things.

Resleeving the cylinders is essentially replacing them. The block is made of aluminum and the cylinders are "sleeves" for the pistons to move in, made out of iron. Resleeving the block means installing new cylinders.

inspyral

If you're looking for torque from a B16A, you're looking in the wrong place.

livelyjay

well if that is the case, then what about the QR25 engine from Nissan (for those of you who don't know it's the engine in the Sentra SE-R)? That engine puts out a lot of torque and a lot of hp for a 4 cylinder engine. what exactly is done what you "port out" the head?

1stGenCRXer

Apples and oranges You're not going to get super impressive torque from a sub-2.0L honda.

inspyral

Intake and exhaust ports are smoothed out and opened up slightly, valve guides are sometimes ground down, combustion chambers can be reworked, all in order to increase flow in and out of the head.

qtiger

The term porting is a leftover from old American Iron heads, where you would typically "hog out" the ports as much as possible, literally boring out the ports to the largest available size. This produced more power simply because the engines didn't flow very well in the first place, and there was practically nothing you could do to make flow any worse.

On import heads, it is more of a portmatching and polishing process.

P&P cliffs notes:
They match the ports to the gasket size, but do not remove excess material. Next they remove any casting flaws or flash, and polish the surface relatively smooth (not a mirror polish, some roughness is good.)

Next they just clean up all the angles inside the port, do a valve job (3 angle, 5 angle, radius, whatever), and polish out the combustion chambers.

livelyjay

so when you resleeve the cylinders, what is a good material to use and where can you get new sleeves? what other internals can be changed out other than valve springs, cams, sleeves, pistons, and shafts?

1stGenCRXer

Several companies make new sleeves for Honda blocks, Darton would be my off-the-top-of-my-head choice, and normally you can see anything from ductile steel to chromoly listed in the cylinder materials list. I would go by the manufacturer's recommended use more than worrying about what they're made out of.

As far as what other materials can be changed out. You can change cranks, rods, basically anything that bolts into or on an engine can be changed if you really want to. Although sometimes there's no direct part to replace it, in which case you'd be looking at custom stuff [$$].