How to make Horsepower

Volumetric Proficiency · 04-01-2007, 12:45 AM

There is a definate lack of tech on this site, i thought i would condense a few basic ideas regarding the internal combustion engine, and some Honda specific stuff into one post to help people out. Whole books have been written on this subject, and im not going to try to compete with that. The following is just a brief collection of thoughts designed to get you headed in the right direction.

Cylinder Head
An internal combustion engine makes TQ and HP by sucking air through the cylinder head and into the cylinders. It then compresses the air and fuel mixture, lights it off, and uses the energy released to drive the wheels of your automobile. So even in this simplest explanation of how an engine works, it stands to reason that the more air you can get into the cylinders, the more power you will make, right? Of course its never that simple.

A cylinder head with a valve job and ports designed to optimize power at 9000rpm will almost always sacrifice power below 6000rpm. Bigger is definately not better when it comes to cylinder head ports, especially with Honda engines. The ports are usually pretty generous in size from the factory, especially in builds where the stock displacement is kept. Most all motor builds can get by with a good 3 angle valve job, and then blending the valve job into the throat area. There is NO, i repeat NO power to be gained by modifying the port entry.

Once you start stepping up your build however, to a stroker or maybe just an extra high RPM 1.6 liter, the need for improved breathing becomes very apparent. The cylinder head is THEE most important part of any serious high performance build. This is where your capacity for HP is determined. Read the first paragraph of this section again to understand why.

Camshafts. Pick your cam based on two things. The RPM you are willing to turn and the flow capability of your head. Camshafts are a real complicated subject that deserve their own post, if you want to ask specific questions, ill try my best to answer them later in this thread.

Block
The block has a few duties. To provide a decent 'sucking' (vacuum) action to draw air in through the cylinder head, to compress the mixture that was drawn in and to not fly apart when the revs start to build and the power comes on. Starting at the very bottom, Honda cranks are exceptional in regards to the amount of abuse they can take. They are very high quality peices and i see absolutely no reason to run an aftermarket crank, unless it is of a stroke length that Honda does not offer. I dont like 'knife edged' cranks on street setups for a few reasons. The counterweights are there for a reason, and the minute difference in makes on most street apps does not warrant the weakening of the crankshaft due to the material removed.

As far as rods go, stock Honda rods are real good. And can take up to about 50hp over what the engine is rated at stock before i would start thinking about upgrading. A good cheap upgrade is ARP rod bolts. Everyone knows them, theyre everywhere, theyre not expensive. Buy them, lube them, TQ them properly and you will be happy. No one thinks about rods too much until they have one fail on them.

Pistons. Again, stock Honda pistons are real good. I put them in the same category as Honda rods. About 50hp over stock and you start asking for trouble. You can get away with a little more, but you need to be extra careful with tuning on stock Honda pistons as they dont cope as nicely with heat and detonation as their forged counterparts. The most important part of the piston is the ring package and the piston to wall clearance. The ring end gaps must be set EXACTLY according to specs to produce max HP and the piston to wall clearance needs to be EXACT as well to ensure a stable piston condition. Not one thats free to rock in back in forth in the bore .001-.002" more than it should be.

Bearings
Honda has some real good bearings, when building be sure to go for the VTEC style rod bearings, they are a tri-metal design and have far better oil retention characteristics than the non-VTEC bi-metal design. This is important for when RPM starts to skyrocket and stuff gets real hot. As far as main bearings , the hot ticket from Honda is the K series stuff. It is the same width as the B series main bearing, so you can use them in B blocks. They are of the coated variety though, and i have had several people ask me "why run coated bearings if the crank never actually touches them during operating conditions?" Well, something like 90% of engine wear occurs during cold start up. You think theres a nice thick film of oil in between your crankshaft and your bearing for the first 3 seconds of running on a cold winter morning? You bet your sweet ass there isnt.

Ok, so this post is a work in progress and is very general. Any questions you might have, im here to answer if i can, and ill probably add to this as i see fit.

knuckk · 04-01-2007, 12:52 AM

holy shitt smart ass brotha sticky this mods

Gil'sEJ6 · 04-01-2007, 01:00 AM

pretty good right up... but its a lil general... not hating but a lot of people on here know that already... bump

Volumetric Proficiency · 04-01-2007, 01:01 AM

Quote:

Originally Posted by EKfreak

pretty good right up... but its a lil general... not hating but a lot of people on here know that already... bump

Its intended to be. Engine operation doesnt change from one engine to another just because one says Honda and the other says Nissan.

If you want specifics, ask me some stuff and ill add it.

***Pootie*** · 04-01-2007, 01:16 AM

Quote:

Originally Posted by EKfreak

pretty good right up... but its a lil general... not hating but a lot of people on here know that already... bump

what better place than the BEGINNING....who knew it get a REVISE,, who didn't LEARN..

Gil'sEJ6 · 04-01-2007, 01:26 AM

Quote:

Originally Posted by Pootie

what better place than the BEGINNING....who knew it get a REVISE,, who didn't LEARN..

couldnt of said it better myself.. works out for everyone

fastintegra · 04-01-2007, 01:38 AM

def get this stickyd...very informative....nice write up and def helpful to noobs like me that havent really built there own engine yet....add more too

Volumetric Proficiency · 04-01-2007, 06:48 PM

So what do you guys have questions about that you wuold like to see added?

hoshichi · 04-01-2007, 07:16 PM

what would be the best way to go about choosing a set of cams for a specific build???? what cams give the most benefit for a stock bottom end setup???
and why??? what relationship do the cams have to the bottom end regarding the compression? and why does the static compression ratio seem to be one of the most important factors in cam selection???
sorry if these questions are a bit vague.......
i guess this is where the learning curve starts to get a bit more steep!
so its difficult to word the questions to get the answers im looking for.....
thanks much!!!!!

hoshichi · 04-01-2007, 07:34 PM

go away crump20........really......do us the kind service of making your self dissapear........
finally someone on here has something informative to tell in way that most can absorb it........lets show a bit more gratitude for someone whose wisdom is more of a blessing to this forum than about 97% of the people wasting their time on here......

04-01-2007, 12:45 AM	#1 (permalink)
Volumetric Proficiency Noob Join Date: Jul 2006 Posts: 174 iTrader: (0)	How to make Horsepower There is a definate lack of tech on this site, i thought i would condense a few basic ideas regarding the internal combustion engine, and some Honda specific stuff into one post to help people out. Whole books have been written on this subject, and im not going to try to compete with that. The following is just a brief collection of thoughts designed to get you headed in the right direction. Cylinder Head An internal combustion engine makes TQ and HP by sucking air through the cylinder head and into the cylinders. It then compresses the air and fuel mixture, lights it off, and uses the energy released to drive the wheels of your automobile. So even in this simplest explanation of how an engine works, it stands to reason that the more air you can get into the cylinders, the more power you will make, right? Of course its never that simple. A cylinder head with a valve job and ports designed to optimize power at 9000rpm will almost always sacrifice power below 6000rpm. Bigger is definately not better when it comes to cylinder head ports, especially with Honda engines. The ports are usually pretty generous in size from the factory, especially in builds where the stock displacement is kept. Most all motor builds can get by with a good 3 angle valve job, and then blending the valve job into the throat area. There is NO, i repeat NO power to be gained by modifying the port entry. Once you start stepping up your build however, to a stroker or maybe just an extra high RPM 1.6 liter, the need for improved breathing becomes very apparent. The cylinder head is THEE most important part of any serious high performance build. This is where your capacity for HP is determined. Read the first paragraph of this section again to understand why. Camshafts. Pick your cam based on two things. The RPM you are willing to turn and the flow capability of your head. Camshafts are a real complicated subject that deserve their own post, if you want to ask specific questions, ill try my best to answer them later in this thread. Block The block has a few duties. To provide a decent 'sucking' (vacuum) action to draw air in through the cylinder head, to compress the mixture that was drawn in and to not fly apart when the revs start to build and the power comes on. Starting at the very bottom, Honda cranks are exceptional in regards to the amount of abuse they can take. They are very high quality peices and i see absolutely no reason to run an aftermarket crank, unless it is of a stroke length that Honda does not offer. I dont like 'knife edged' cranks on street setups for a few reasons. The counterweights are there for a reason, and the minute difference in makes on most street apps does not warrant the weakening of the crankshaft due to the material removed. As far as rods go, stock Honda rods are real good. And can take up to about 50hp over what the engine is rated at stock before i would start thinking about upgrading. A good cheap upgrade is ARP rod bolts. Everyone knows them, theyre everywhere, theyre not expensive. Buy them, lube them, TQ them properly and you will be happy. No one thinks about rods too much until they have one fail on them. Pistons. Again, stock Honda pistons are real good. I put them in the same category as Honda rods. About 50hp over stock and you start asking for trouble. You can get away with a little more, but you need to be extra careful with tuning on stock Honda pistons as they dont cope as nicely with heat and detonation as their forged counterparts. The most important part of the piston is the ring package and the piston to wall clearance. The ring end gaps must be set EXACTLY according to specs to produce max HP and the piston to wall clearance needs to be EXACT as well to ensure a stable piston condition. Not one thats free to rock in back in forth in the bore .001-.002" more than it should be. Bearings Honda has some real good bearings, when building be sure to go for the VTEC style rod bearings, they are a tri-metal design and have far better oil retention characteristics than the non-VTEC bi-metal design. This is important for when RPM starts to skyrocket and stuff gets real hot. As far as main bearings , the hot ticket from Honda is the K series stuff. It is the same width as the B series main bearing, so you can use them in B blocks. They are of the coated variety though, and i have had several people ask me "why run coated bearings if the crank never actually touches them during operating conditions?" Well, something like 90% of engine wear occurs during cold start up. You think theres a nice thick film of oil in between your crankshaft and your bearing for the first 3 seconds of running on a cold winter morning? You bet your sweet ass there isnt. Ok, so this post is a work in progress and is very general. Any questions you might have, im here to answer if i can, and ill probably add to this as i see fit.

04-01-2007, 12:52 AM	#2 (permalink)
knuckk Senior Member Join Date: Jul 2006 Location: CT Posts: 8,484 iTrader: (6)	holy shitt smart ass brotha sticky this mods __________________ NO LIFE CREW MEMBER#9 STOP SUPPORTING THEIVES. DONT BUY STOLEN PARTS. "EK SQUAD" East Coast Movement

04-01-2007, 01:00 AM	#3 (permalink)
Gil'sEJ6 Senior Member Join Date: Nov 2006 Location: NJ Posts: 10,296 iTrader: (12)	pretty good right up... but its a lil general... not hating but a lot of people on here know that already... bump __________________ OUT OF THE GAME AND PROUD CREW MEMBER #1

Thread Tools
Show Printable Version Email this Page
Display Modes
Linear Mode Switch to Hybrid Mode Switch to Threaded Mode

04-01-2007, 01:38 AM	#7 (permalink)
fastintegra Senior Member Join Date: Jun 2004 Location: strong island Posts: 1,527 iTrader: (0)	def get this stickyd...very informative....nice write up and def helpful to noobs like me that havent really built there own engine yet....add more too

04-01-2007, 06:48 PM	#8 (permalink)
Volumetric Proficiency Noob Join Date: Jul 2006 Posts: 174 iTrader: (0)	So what do you guys have questions about that you wuold like to see added?

04-01-2007, 07:16 PM	#9 (permalink)
hoshichi Member Join Date: Dec 2005 Location: H.P.I. high performance imports Posts: 743 iTrader: (0)	what would be the best way to go about choosing a set of cams for a specific build???? what cams give the most benefit for a stock bottom end setup??? and why??? what relationship do the cams have to the bottom end regarding the compression? and why does the static compression ratio seem to be one of the most important factors in cam selection??? sorry if these questions are a bit vague....... i guess this is where the learning curve starts to get a bit more steep! so its difficult to word the questions to get the answers im looking for..... thanks much!!!!!

04-01-2007, 07:34 PM	#10 (permalink)
hoshichi Member Join Date: Dec 2005 Location: H.P.I. high performance imports Posts: 743 iTrader: (0)	go away crump20........really......do us the kind service of making your self dissapear........ finally someone on here has something informative to tell in way that most can absorb it........lets show a bit more gratitude for someone whose wisdom is more of a blessing to this forum than about 97% of the people wasting their time on here......

B20vtec.com