that looks like a turbo application piston...but definitely interesting. In the Honda community...we found that deep valve reliefs and certain intake porting worked for better atomonization proved potent.

here is my old honda piston

 

wow this was a good thread, i need a cig and i dont smoke lol

I feel like I just learned more reading this whole thread then ive learned in years...of course I am newb!!

holy crap good reading!!!!

 

So after three days of reading this thread, and learning more than I did in 13 weeks of military engineering school, I must offer my voice to supplement the chorus of thanks and kudos to the author of this thread.

In addition, let me add a polite 'bump' to the best internet discussion article I have ever read!

 

This thread should never die... it shows someone who actually did some research and found out that the xB engine is already pretty much maxed out and not much room for improvement... Kudos to twiddler for the info

 

Sorry...I know this is somewhat old.

Heads don't "make" compression, but they affect the dynamic compression ratio. This is what really matters in an engine, not the static rating of a piston. This may have already been said...I skipped some stuff. Milling a head will definitely change the effective compression ratio of an engine.

Also, one thing to beware of when milling heads: get adjustable timing gear(s). The small change in distance between the crank and cam gear can be enough to retard the engine's base timing. Not by much, but it does happen.

 

Wow, this is an amazing thread...it should be stickied.

Its really sad though that the realization has finally hit me....without boost, the xB will never be fast.
Unless somone can fully map the ecu and do some crazy hondata stuff for us.

 

bump

 

Try this for info DG..........

How Car Engines Work

by Marshall Brain



Table of Contents
Introduction to How Car Engines Work Cylinders, Displacement and Other Engine Parts Valve Trains and Systems Producing More Power, Engine Questions Lots More Information Compare Prices for Car Engines







Cylinders, Displacement and Other Engine Parts
The core of the engine is the cylinder, with the piston moving up and down inside the cylinder. The engine described above has one cylinder. That is typical of most lawn mowers, but most cars have more than one cylinder (four, six and eight cylinders are common). In a multi-cylinder engine, the cylinders usually are arranged in one of three ways: inline, V or flat (also known as horizontally opposed or boxer), as shown in the following figures.






Click on image to see animation
Figure 4. Flat - The cylinders are arranged in two banks on opposite sides of the engine.
Different configurations have different advantages and disadvantages in terms of smoothness, manufacturing-cost and shape characteristics. These advantages and disadvantages make them more suitable for certain vehicles.


The combustion chamber is the area where compression and combustion take place. As the piston moves up and down, you can see that the size of the combustion chamber changes. It has some maximum volume as well as a minimum volume. The difference between the maximum and minimum is called the displacement and is measured in liters or CCs (Cubic Centimeters, where 1,000 cubic centimeters equals a liter).


An internal combustion engine
Spark plug
The spark plug supplies the spark that ignites the air/fuel mixture so that combustion can occur. The spark must happen at just the right moment for things to work properly.

Valves
The intake and exhaust valves open at the proper time to let in air and fuel and to let out exhaust. Note that both valves are closed during compression and combustion so that the combustion chamber is sealed.

Piston
A piston is a cylindrical piece of metal that moves up and down inside the cylinder.

Piston ringsPiston rings provide a sliding seal between the outer edge of the piston and the inner edge of the cylinder. The rings serve two purposes:

They prevent the fuel/air mixture and exhaust in the combustion chamber from leaking into the sump during compression and combustion.
They keep oil in the sump from leaking into the combustion area, where it would be burned and lost.
Most cars that "burn oil" and have to have a quart added every 1,000 miles are burning it because the engine is old and the rings no longer seal things properly.
Connecting rod
The connecting rod connects the piston to the crankshaft. It can rotate at both ends so that its angle can change as the piston moves and the crankshaft rotates.

Crank shaft
The crank shaft turns the piston's up and down motion into circular motion just like a crank on a jack-in-the-box does.

Sump
The sump surrounds the crankshaft. It contains some amount of oil, which collects in the bottom of the sump (the oil pan).



Home Store Newsletter Search Advertising Privacy Terms and Conditions Contact About Help
© 1998 - 2006 HowStuffWorks, Inc

This info was found during a search on "How Stuff Works" and edited so as to not take up the space.

 

bump

 

Frogbox, I think people have a hard time understanding the difference between compression RATIO and compression as in cylinder pressure or PSI. I gave up on arguing over it months ago...and I see it popped up again. Oh well. Thank you though, for the good resources and posting them here. I think a LOT of us (including me) can stand to learn a few things just by reading a little.

 

Overall end, could the xB owner achive the 24whp with those mods?

 

i wanna hear more about the thing with the temp on the MAF and mabey pics? and howto's because that honestly lost me lol

 

This is my take, pistons don't make the compression, nor do the heads. The whole package is what makes the compression. If you could slide the block up and down on a fixed piston it would make the same compression. Lose any of the sealing components and you will have no compression; piston, rings, cylinder walls(block), vales or head.

 

Most likely no. If we could have easier access to the fuel injection system computer...it would be close because then it would be much easier to play with the timing curve and rich/lean circuits. With the mods I used, you are most likely looking in the 9-12HP range realistically.

If anyone wants a cat back...read on!
I couldn't take the ringing in my ears on long drives to northern california. lol And so I gave up a little HP for my ears. If anyone is interested in my Magnaflow system that I used in the tests, here it is listed on ebay. The two brackets aren't there but brackets aren't too hard to find at hardware stores or mcmaster carr.
http://cgi.ebay.com/ebaymotors/ws/eB...m=250050093563


hope your rides are running well.

Andy

 

will the magnaflow fit an xA?

 

I don't think it will...here is the official page from the MagnaFlow site. I think they might offer an Xa model though.
http://hardware.silicon.com/desktops...9164083,00.htm

Here is the install pdf is anyone wonders how hard it is to install. You basically need a saw to cut the existing system, and then a 2" and 2.5" clamp. Its a fun 2-3 hour project without too much swearing. lol
http://www.magnaflow.com/07techtips/pdfs/15822.pdf

 

MagnaFlow does offer an xA setup. Chops has it, and loves it. I think it's what I'll get when I have the money.

the only thing I can say is, WOW! this really should be sticky, and if you read this post, go back and read the rest!



Also quick Intake ? for Twiddler....Did you notice that your intakes (short/long) added power in different places on the RPM band?

 

I can't really remember but I think it was fairly consistant throughout the rpm band.

 

so nothing like headers where the 4-2-1 is for low/mid-range and 4-1 are for high range?

 

It seems the longer intake tubes tend to make a little more power overall but I don't know why that is...I would guess that it does two things:

1. cools the air
or grabs cooler air since it is longer so you are grabbing air further away from the hot engine.

2. smooths the air
the nice long channel may bring the air into the intake with less turbulants. I'm just guessing.

there probably is a rule of thumb that longer pipes are for lower revs and shorter for higer but I think its always best to test and see.