please. Please. do not tell me to search. i just want to have all the answers be directly related to my questions, and not close to it, ans you would get wiith a search.
also asking this here puts all my info in one thread, and makes it easier to ask questions to replies and keep track of the overall thread.

with this said...

i know a very good ammount of info on enignes... i know how they work, all basic knowledge, sohc, dohc, etc.

but recently i've been looking at engine swaps, rebuilds and stuff like that, and i've hit a wall of info that i have no clue as to what it is...

can someone explain basics of that?

for instance, non-vtec bottoms, vtec heads, etc. what is all this, what do they do?

 

check out the hybrids forum..your questiuon is TOO broad for anyone to know what you actually need to know.

I'm sorry but the best answer your possibly going to get is "DO A SEARCH"

or else try to be more specific in what you want to know..for example- what gains is there to be had from adding a B20 bottom end to a B16 head or something like that!

 

using a crankshaft with a bigger stoke will go down further (piston) and by doing this draw more air inside the combustion chamber and compress it aswell basically breathing more air.. you compress more air you get more power with the righ mixture of the fuel however with a long stoke it's not designed for high rpm usage because the bottom end will most likely loose balance before a shorter stroke....

 

VTEC uses two cam lobes, optimising torque at two rpm values insteaed of one.

Because torque at low rpms and high rpms is increased, this naturally increases the demand for a higher redline. In engines with no VTEC, torque at one rpm value is high but low at other rpm values, which usually results in an overall lower usable rpm range and lower redline.

The demand for a higher redline calls for increasing the strength of VTEC bottom ends. Things like piston oil squirters, better r/s ratios, and sometimes better piston/ rod/ crank materials/manufacturing processes are used (R motors).

Ultimately this meas that VTEC motors can flow more air and handle higher stresses of the higher rpm values. They makes more power more reliably.


[Modified by Lsos, 8:12 AM 10/30/2002]

 

what is a head and bottom? how does it provide a longer stroke?


[Modified by 95si, 8:52 AM 10/30/2002]

 

Head is the top piece of the engine.

It's where the cams, valves, etc is. You can make a non-VTEC engine into a VTEC engine simply by putting a VTEC head on it, although the bottom won't be properly prepared for the higher rpms..

Bottom is the block.

The cylinders, pistons, crank are there. To get a longer stroke you simply change the crank. Other pieces will then need to be changed (shorter rods) to keep proper clearances.



[Modified by Lsos, 7:30 PM 10/30/2002]

 

check IM.