b16a high revs why not b18b?
Jszy
02-23-2004, 06:22 PM
I was wondering what makes the b16a rev so much higher then the b18b? the b18b redlines at like 6800 while the b16 is like 8200. Is it a shorter stroke? or does it have to do with the compression?? Please post an answer if you really know wut your talking about.....not like most of you bull shitters who like to hear themselves.
boosted331
02-23-2004, 07:27 PM
The reason the B16 revs higher than the B18A/B in stock form is a combination of many factors
Stroke - 77MM vs. 89MM. The smaller stroke motor revs quicker and requires more rev's to make power. Remember horsepower is derived from torque, so you move x amount of torque up in the rev band and you make more power.
Cylinder Head - They B16's head flows much, MUCH better than the B18A/B18B head, which allows it to make power efficiently to higher RPM's. This is also why LS/VTEC turbo setups make more power than straight LS turbo setups, a more efficient cylinder head.
Camshafts - The B16's vtec cams are ground with more lift and duration to allow the motor to make power higher in the RPM band. Not much else to say about this.
Motor Design - The B16A was designed for use in lighter civics, where peak power is more important than low-end grunt to get you off the line, where the B18A/B motors were designed primarily for economy and low end power.
Stroke - 77MM vs. 89MM. The smaller stroke motor revs quicker and requires more rev's to make power. Remember horsepower is derived from torque, so you move x amount of torque up in the rev band and you make more power.
Cylinder Head - They B16's head flows much, MUCH better than the B18A/B18B head, which allows it to make power efficiently to higher RPM's. This is also why LS/VTEC turbo setups make more power than straight LS turbo setups, a more efficient cylinder head.
Camshafts - The B16's vtec cams are ground with more lift and duration to allow the motor to make power higher in the RPM band. Not much else to say about this.
Motor Design - The B16A was designed for use in lighter civics, where peak power is more important than low-end grunt to get you off the line, where the B18A/B motors were designed primarily for economy and low end power.
jcrx
02-24-2004, 02:30 AM
Fuckin' A, couldn't have said it better myself. I was expecting to see the old "I don't know shit, so I'm just going to say the r/s it better" routine, :::golfclap:::
killah_xft
02-24-2004, 06:08 AM
I have one last bit to add. It's not much but it is a factor.
The sheer mass of a larger piston makes it harder for a cylinder larger than the b16 to rev much higher.
take for instance a 5 HP lawnmower engine which spins at a good 2000-3000 RPMs.. well take my R/C engine (2 stroke nitro) I have in my XXXnt it revs at a good 29,000 rpm's (not even considered fast in the R/C world (40-42,000rpms is fastest revs possible)) while the lawnmower piston is about 6-8 times larger than the nitro engine, and has to move so much more mass.
Just thought I'd add that.
The sheer mass of a larger piston makes it harder for a cylinder larger than the b16 to rev much higher.
take for instance a 5 HP lawnmower engine which spins at a good 2000-3000 RPMs.. well take my R/C engine (2 stroke nitro) I have in my XXXnt it revs at a good 29,000 rpm's (not even considered fast in the R/C world (40-42,000rpms is fastest revs possible)) while the lawnmower piston is about 6-8 times larger than the nitro engine, and has to move so much more mass.
Just thought I'd add that.
93civicsiracer
05-01-2006, 03:22 AM
ok i see were u where going with that. ok so correct me if im wrong just to see if its clicking in my head. basically both objects are doing the samething but because of weight, the smaller object is able to rev higher correct.
is there a weight difference between the 2 engines. and does that matter in overall performance.
is there a weight difference between the 2 engines. and does that matter in overall performance.
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