Sport Compact Disses Mazda Motor Company
04-08-2003, 04:49 PM
#52
Senior Member
Join Date: Oct 2002
Posts: 123
the way i understand it, the displacement of a boinger is measured by two full rotations of the crankshaft. so that all pistons fire. but this means that all pistons are at TDC and BDC twice each. if they are just measuring the air that is taken in then it would be correct, but if they measure the displacement twice, they would get twice the actual disp.
a rotary is not a piston engine though, and while they admit is different from a piston engine they still want to measure it the same way. there are two ways you can look at it compared to a boinger. you can consider each rotor equal to 3 pistons or each rotor equal to 1 piston. the latter is correct since 1 rotor can only provide power from 1 surface at a time. NOW, the piston engine may take 2 rotations to fire all chambers but the rotary only takes 1. so measuring the displacement by two full rotations is stupid. the displacement on each face is 654. 1 rotation to fire both chambers =1308cc. measuring it as 2616cc is like saying each rotor is equal to two pistons.
boingers just cant stand the fact that we get this much power out of so little displacement, plus ridiculous rpm range.
let them "Babble" i know better than to go to SCC for my info and so should everyone here
Justin
a rotary is not a piston engine though, and while they admit is different from a piston engine they still want to measure it the same way. there are two ways you can look at it compared to a boinger. you can consider each rotor equal to 3 pistons or each rotor equal to 1 piston. the latter is correct since 1 rotor can only provide power from 1 surface at a time. NOW, the piston engine may take 2 rotations to fire all chambers but the rotary only takes 1. so measuring the displacement by two full rotations is stupid. the displacement on each face is 654. 1 rotation to fire both chambers =1308cc. measuring it as 2616cc is like saying each rotor is equal to two pistons.
boingers just cant stand the fact that we get this much power out of so little displacement, plus ridiculous rpm range.
let them "Babble" i know better than to go to SCC for my info and so should everyone here
Justin
04-08-2003, 05:26 PM
#53
Super Moderator
Join Date: Feb 2002
Location: Amityville, New York
Posts: 12,288
Originally Posted by Apex13B' date='Apr 7 2003, 06:34 PM
302 = 5.0 ford
305 = chevy small block.
just to be a picky ******* boinger builder, my ford BDD atlantic motor did 22 9800 rpm dyno pulls today
305 = chevy small block.
just to be a picky ******* boinger builder, my ford BDD atlantic motor did 22 9800 rpm dyno pulls today
04-08-2003, 07:06 PM
#54
Senior Member
Join Date: Oct 2002
Location: Tallahassee FL
Posts: 345
so if i'm understanding this correctly.. in terms of 'real' displacement.. the 'boinger' method is twice the real displacement.. and the mazda method is the real displacement.. ? or do they both reflect the real displacement.. and the modification in the formula is necessary to make up for the physical differences
i'm going off of what i've understood from Muad'Dibs post
i'm going off of what i've understood from Muad'Dibs post
04-08-2003, 09:15 PM
#55
Senior Member
Join Date: Jan 2003
Location: London, Ontario
Posts: 2,871
Originally Posted by Muad'Dib' date='Apr 8 2003, 04:49 PM
the way i understand it, the displacement of a boinger is measured by two full rotations of the crankshaft. so that all pistons fire. but this means that all pistons are at TDC and BDC twice each. if they are just measuring the air that is taken in then it would be correct, but if they measure the displacement twice, they would get twice the actual disp.
a rotary is not a piston engine though, and while they admit is different from a piston engine they still want to measure it the same way. there are two ways you can look at it compared to a boinger. you can consider each rotor equal to 3 pistons or each rotor equal to 1 piston. the latter is correct since 1 rotor can only provide power from 1 surface at a time. NOW, the piston engine may take 2 rotations to fire all chambers but the rotary only takes 1. so measuring the displacement by two full rotations is stupid. the displacement on each face is 654. 1 rotation to fire both chambers =1308cc. measuring it as 2616cc is like saying each rotor is equal to two pistons.
boingers just cant stand the fact that we get this much power out of so little displacement, plus ridiculous rpm range.
let them "Babble" i know better than to go to SCC for my info and so should everyone here
Justin
a rotary is not a piston engine though, and while they admit is different from a piston engine they still want to measure it the same way. there are two ways you can look at it compared to a boinger. you can consider each rotor equal to 3 pistons or each rotor equal to 1 piston. the latter is correct since 1 rotor can only provide power from 1 surface at a time. NOW, the piston engine may take 2 rotations to fire all chambers but the rotary only takes 1. so measuring the displacement by two full rotations is stupid. the displacement on each face is 654. 1 rotation to fire both chambers =1308cc. measuring it as 2616cc is like saying each rotor is equal to two pistons.
boingers just cant stand the fact that we get this much power out of so little displacement, plus ridiculous rpm range.
let them "Babble" i know better than to go to SCC for my info and so should everyone here
Justin
You have hit the nail on the head as to why I believe the argument comes up, though. Each combustion face in a rotary approaches the spark plugs (TDC) once per combustion event. The 4-stroke piston engine does it twice, only bringing in fresh air / fuel mixture once. Therefore the rotary moves twice as much fresh air / fuel mixture as a 4-stroke piston engine with the same DISPLACEMENT.
04-08-2003, 09:29 PM
#56
Senior Member
Join Date: Nov 2002
Location: Colorado Springs
Posts: 1,679
Originally Posted by Rob x-7' date='Apr 8 2003, 05:26 PM
[quote name='Apex13B' date='Apr 7 2003, 06:34 PM'] 302 = 5.0 ford
305 = chevy small block.
just to be a picky ******* boinger builder, my ford BDD atlantic motor did 22 9800 rpm dyno pulls today
305 = chevy small block.
just to be a picky ******* boinger builder, my ford BDD atlantic motor did 22 9800 rpm dyno pulls today
strange...i built a 302 ford Trans-Am series motor today, then milled down a chevy to displace the same amount with a destroked crank...humm
dont make me come over there and beat you up rob
04-08-2003, 11:04 PM
#58
Senior Member
Thread Starter
Join Date: Dec 2002
Location: QUEENS NYC
Posts: 1,687
Originally Posted by UniqueTII' date='Apr 8 2003, 01:35 PM
I've noticed a lot of rotary engine questions on other forums because of that article too.
Let's clean this thread up before it gets locked, okay?
Let's clean this thread up before it gets locked, okay?
Thread
Thread Starter
Forum
Replies
Last Post
rx794
Race Prep
2
04-13-2007 01:13 AM
vaughnc
2nd Generation Specific
0
08-04-2002 02:08 AM
Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)