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BooRadley · 11-02-2003, 06:07 PM

My information was slightly flawed. I had read ( don't trust the internet, kids

that the CR was with boost factored in ( as obviously boost increases CR ). If it can run on pump gas, then that seemed like a reasonable number to me with boost factored in. I doubt you could maintain an effective ratio of 15:1 without race gas or water injection... but then again, I don't know everything. Some people run 24 psi with 93 octane in their Eclipses, so I'm not the turbo master,and I'll be the first to admit that.

I still maintain the seals are far from perfect ( Aforementioned track record of failing seals and rebuilds every 80-90k miles ) and that 9.7 CR wouldn't hold for long and things would get worse... some people swear 150k, some people swear 200k, but I think many of these owners bought a car that has had an engine rebuilt once.... I have 4 friends whom have owned RX7s of varying generations, and all are pretty adamant about the 80k limit with the exception of new cars that have been religiously maintained and not ragged out.

Don't get me wrong. I'm not hating on the rotaries in anyway . I think they are great.
But their added horsepower adds increased fuel consumption. If you have a 1.3L rotary, you will consume alot more fuel than a 1.3L NA street engine unless it has a race build on it....

I found a cool article on Dragsport.com, http://www.dragsport.com/dept/tech/2/ comparing rotaries to pistons, definitely worth a check. It outlines compression ratios like I have and their effects on performance.

Something I have failed to point out that this article illustrates is the fact that the rotary has a power stroke every 270 degrees... instead of every 720 degrees for regular reciprocating engines. This is definitely a reason why rotaries produce much more power. Read the article for more info.

11-02-2003, 06:07 PM	#18 (permalink)
BooRadley Insane Location: Kentucky	My information was slightly flawed. I had read ( don't trust the internet, kids that the CR was with boost factored in ( as obviously boost increases CR ). If it can run on pump gas, then that seemed like a reasonable number to me with boost factored in. I doubt you could maintain an effective ratio of 15:1 without race gas or water injection... but then again, I don't know everything. Some people run 24 psi with 93 octane in their Eclipses, so I'm not the turbo master,and I'll be the first to admit that. I still maintain the seals are far from perfect ( Aforementioned track record of failing seals and rebuilds every 80-90k miles ) and that 9.7 CR wouldn't hold for long and things would get worse... some people swear 150k, some people swear 200k, but I think many of these owners bought a car that has had an engine rebuilt once.... I have 4 friends whom have owned RX7s of varying generations, and all are pretty adamant about the 80k limit with the exception of new cars that have been religiously maintained and not ragged out. Don't get me wrong. I'm not hating on the rotaries in anyway . I think they are great. But their added horsepower adds increased fuel consumption. If you have a 1.3L rotary, you will consume alot more fuel than a 1.3L NA street engine unless it has a race build on it.... I found a cool article on Dragsport.com, http://www.dragsport.com/dept/tech/2/ comparing rotaries to pistons, definitely worth a check. It outlines compression ratios like I have and their effects on performance. Something I have failed to point out that this article illustrates is the fact that the rotary has a power stroke every 270 degrees... instead of every 720 degrees for regular reciprocating engines. This is definitely a reason why rotaries produce much more power. Read the article for more info. Last edited by BooRadley; 11-02-2003 at 06:11 PM..