DD with different portings
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DD with different portings
Just curious, with the SP, BP, and PP.. how much harder or more worse is it when you go up in porting levels in terms of daily driving? I know SP is perfectly fine, but once you hit BP or PP.. how bad is it, and how so?
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Just compare the BP to a piston engine with a much larger cam. Poor idle, poor fuel economy, etc..
A PP would be a piston engine with a god awful cam in it. Meaning it would have a real choppy idle and you would have to turn the idle way up to keep it from dying. The fuel economy for the most part would go way down.
Not you best choice to use for a daily driver.
A PP would be a piston engine with a god awful cam in it. Meaning it would have a real choppy idle and you would have to turn the idle way up to keep it from dying. The fuel economy for the most part would go way down.
Not you best choice to use for a daily driver.
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Just compare the BP to a piston engine with a much larger cam. Poor idle, poor fuel economy, etc..
A PP would be a piston engine with a god awful cam in it. Meaning it would have a real choppy idle and you would have to turn the idle way up to keep it from dying. The fuel economy for the most part would go way down.
Not you best choice to use for a daily driver.
A PP would be a piston engine with a god awful cam in it. Meaning it would have a real choppy idle and you would have to turn the idle way up to keep it from dying. The fuel economy for the most part would go way down.
Not you best choice to use for a daily driver.
#6
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I wouldn't worry so much about MPG as I would actual drivability. Yeah there's people who have done it but I don't think it's recommended. I think a 1/2 Bridge is about as big as I would go for DD and that's still pushing it. The problem is the powerband shifts into the upper range so street driving is sacrificed quite a bit. Below 3k RPMs it'll buck and bog basically while trying to cruise. Not to mention, the bigger the port, the louder it gets
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I wouldn't worry so much about MPG as I would actual drivability. Yeah there's people who have done it but I don't think it's recommended. I think a 1/2 Bridge is about as big as I would go for DD and that's still pushing it. The problem is the powerband shifts into the upper range so street driving is sacrificed quite a bit. Below 3k RPMs it'll buck and bog basically while trying to cruise. Not to mention, the bigger the port, the louder it gets
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Just compare the BP to a piston engine with a much larger cam. Poor idle, poor fuel economy, etc..
A PP would be a piston engine with a god awful cam in it. Meaning it would have a real choppy idle and you would have to turn the idle way up to keep it from dying. The fuel economy for the most part would go way down.
Not you best choice to use for a daily driver.
A PP would be a piston engine with a god awful cam in it. Meaning it would have a real choppy idle and you would have to turn the idle way up to keep it from dying. The fuel economy for the most part would go way down.
Not you best choice to use for a daily driver.
However a Piston engine with a wild cam will idle rough,but smooth out just above idle.Now with a Rotary the reversion makes it allmost no fun to drive at light(small)throttle.The more load you put on a heavilly ported Rotary at lower rpm,the smoother it will be,or select a lower gear,and get the RPM up.It bucks severely when the piston engine just lacks in torque.
Karis
#13
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I used to run a 12A with a 1/2 bridge on the street and it was fine. I just learned to keep my foot into it a little bit. Yes it did buck a fair bit under the 3K rpm range but it also did that on the highway at cruising speeds. It seemed to like WOT more than anything. I know have a 13B peripheral port on the street and i have it idling at 1100 rpm and seems to work pretty well. That engine has no power below 4K rpm but once it hits 4K its like a turbo that just spooled. haha. The 13B-PP bucks as well doesn't like cruising again likes the WOT.
If your worried about fuel economy than RX7's arnt for you. haha. Who buys sports cars and then are concerned how many mpg your going to get. Its kinda like a drag racer concerned about tires.
If your worried about fuel economy than RX7's arnt for you. haha. Who buys sports cars and then are concerned how many mpg your going to get. Its kinda like a drag racer concerned about tires.
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I used to run a 12A with a 1/2 bridge on the street and it was fine. I just learned to keep my foot into it a little bit. Yes it did buck a fair bit under the 3K rpm range but it also did that on the highway at cruising speeds. It seemed to like WOT more than anything. I know have a 13B peripheral port on the street and i have it idling at 1100 rpm and seems to work pretty well. That engine has no power below 4K rpm but once it hits 4K its like a turbo that just spooled. haha. The 13B-PP bucks as well doesn't like cruising again likes the WOT.
If your worried about fuel economy than RX7's arnt for you. haha. Who buys sports cars and then are concerned how many mpg your going to get. Its kinda like a drag racer concerned about tires.
If your worried about fuel economy than RX7's arnt for you. haha. Who buys sports cars and then are concerned how many mpg your going to get. Its kinda like a drag racer concerned about tires.
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Cbz, yes i did read your post those comments were ment as a broad statment. As i can see you like to drive your car and that is why most of us bought our cars.
Drivefast7, yes i have a dual 2" exhaust system on the car now. I have yet to tune the weber as that will be done this winter. The port size is 44mm with a D shape port inside. Going to be installing a turbo II transmission, flywheel, and clutch since i kinda broke some things last race of the year.
Drivefast7, yes i have a dual 2" exhaust system on the car now. I have yet to tune the weber as that will be done this winter. The port size is 44mm with a D shape port inside. Going to be installing a turbo II transmission, flywheel, and clutch since i kinda broke some things last race of the year.
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Cbz, yes i did read your post those comments were ment as a broad statment. As i can see you like to drive your car and that is why most of us bought our cars.
Drivefast7, yes i have a dual 2" exhaust system on the car now. I have yet to tune the weber as that will be done this winter. The port size is 44mm with a D shape port inside. Going to be installing a turbo II transmission, flywheel, and clutch since i kinda broke some things last race of the year.
Drivefast7, yes i have a dual 2" exhaust system on the car now. I have yet to tune the weber as that will be done this winter. The port size is 44mm with a D shape port inside. Going to be installing a turbo II transmission, flywheel, and clutch since i kinda broke some things last race of the year.
I see. sorry for the misunderstanding, and yes of course I do love to drive my car. I honestly couldn't be more happy without my FB
#18
Rotor Power Rules
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I use a half bridge for six months of the year during autocross season. By late summer I'm tired of driving it because it is so much drama. The idle is loud, normal driving is loud, and it hates light throttle. When the cold weather arrives I install a standard port engine and I love it. I'm sure come spring I'll be dying to put the bridge back in.
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