Compression? No VTEC better?
I am sorry but what are you guys talking about?
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Compression? No VTEC better?
I am sorry but what are you guys talking about?
b18c have high compression.Quote:
Originally Posted by Paul1985
turbo's or any other form of forced induction work better with lower compression since it increases the capability of induction.
so the reason some nobbs think b18a/b is better to turbo is since the compression ratio is lower from the factory......i think thats all jus bullshit!!
so go the b16a!!
b18c have high compression.
turbo's or any other form of forced induction work better with lower compression since it increases the capability of induction
Meh Turbo's work BETTER with hi compressioN !!! why go low ?
More videos please! :pQuote:
Originally Posted by BLKCRX
was under the impression that lower compression enables more air to be forced into and compressed for a turbo!!
i had my b18b turbocharged and it had no problems with its stock internal components. BLKCRX obviously knows about turbocharged hondas because he owns 1 as i do. Not sure if u read my thread on my conversion?
by the way, a
b18b has 9-1 comp
b18c has 10-1 comp
b18c type r has 11-1 comp
Any of these can be turbocharged with outstanding results on stock internals and no de comp plates.
lower compression means the engine has a lower detonation pressure, and is less likely to do damage in the event that it detonates. You also have to run a lot more timing to get the power out. Higher compression means you're more liekly to detonate, have a higher detonation pressure, but will make more power per psi, and have a faster spool time most likely.
The reason that VTEC is said to not be good on turbo engines is that on the DOHC vtec engines, there is more overlap on the exhaust cam. Exhaust overlap on a turbo means you're blowing some compressed air straight out the other side of the engine.
Unless you use cam gear's to change the overlap ;) n then make even more power !!!
Regards James
Well this is a really broad question. As an Engineer i can briefly outline a few things for you with turbo charging and choosing a motor.
First off you should know that you can turbo charge any of the above engines safely with the right fuel management. Its highly recommended To run a turbocharged engine at a compression ratio between 8 and 9:1 The idea is that with higher compression, in thermodynamics the otto cycle of a gasoline engine has increased efficiency with higher compression. however the downfall is you have much great chance of preignition of fuel and detonation, two very harmful things for a motor. Mechanical Engineers have a few ways of counteracting these things. 1) Combustion chamber design 2) numerous spark plugs 3) higher octane gas which gives an infinitesimal time delay before the fuel ignites at its normal igniton temperature.
So in conclusion if you can run high octane gas and tune the motor well, any Honda engine is suitable for boost. Ideally you would want something with lower compression or to get in the range stated above. so you can purchase a thicker layered headgasket and this will lower compression. The b18a/b are strong Engines with good compression for boost. They arent made to Rev high. So choose whichever engine is economical for you. Lastly, you might want to consider turbo charging your engine now, message me if you have questions or need help getting started
Cheers
I'd advise against goign with the whole thicker headgasket to lower compression idea... yes, it works, and yes, lots of people do it and have success doing it, but a thicker headgasket is going to blow out easier than a thin one. If you're THAT worried about lowering your compression ratio, do it right. at least imo
I wouldnt touch a decompression plate (thicker gasket) for this very reason alone.
the "Mechanical Octane" obtained as a result of the quench design of 4valve honda head will be lost. This design property along with the exhaust volume bias are what make honda combustion chambers so efficient.
Doing the reverse is not only effectively insulting Honda engineers but decreasing combustion efficiency.
Ive seen a B16 boosting 16psi WITH decompression plate making less power than I am at 4.5psi. If you dont believe me, I'll ask for the graph overlay to prove it.