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Why is it good to rev rotars?

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Old 12-05-10, 12:57 PM
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WA Why is it good to rev rotars?

Can somebody tell me why it is good to redline your rx-7, when it is warmed up, and not totally destroy your engine? Or tell me if its bad...
Old 12-05-10, 09:48 PM
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who told you it was good to redline?
Old 12-05-10, 11:35 PM
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Redline is good to keep carbon build-up down. Just make sure to monitor the temperature when doing so...
Old 12-05-10, 11:45 PM
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it's good to run any engine hard occasionally to keep excess carbon burnt off.
Old 12-06-10, 07:46 AM
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Auxillary injection will also ward off carbon and your not otherwise stressing the engine to do it. Check out the stickys in that section sometime. Great read.
Old 12-06-10, 11:05 AM
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I heard that when turning off the engine, it's good to rev the car to around 3k then shut off the engine while putting your foot to the floor, to clear the fuel out?

Would this not just flood the car?
Old 12-06-10, 12:38 PM
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WA

Originally Posted by RX7_FD3S_JDM
I heard that when turning off the engine, it's good to rev the car to around 3k then shut off the engine while putting your foot to the floor, to clear the fuel out?

Would this not just flood the car?
Well you should let your car warm up at least 15 minutes before reving your engine that high, especially if its cold outside, due to the aluminum, and iron housing on your rotary engine heating up at different rates. Anyways, you shouldn't have to do that everytime you shut off your car, unless you have some kind of engine compression problem, or fuel injector problem. If you do, then reving would get rid of the excess fuel in your engine, to prevent flooding next time you start your engine, because the CPU injects fuel each time you turn your car on, so if there is fuel already in there, it will flood.

The best way to prevent flooding is too NOT turn off your engine too soon after cold starting it.
Old 12-06-10, 01:46 PM
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3k is not high rpm, even at cold. Like stated above, the revving before shutdown is a bandaid for leaky injectors. A redline a day keeps the carbon away.
Old 12-06-10, 01:53 PM
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Originally Posted by rxtasy3
it's good to run any engine hard occasionally to keep excess carbon burnt off.
I agree with rxtasy it is good to stretch the engine out from time to time when under load and it feels good to but I find it hard to believe that reving a engine high when just sitting and not under load could be a good thing rotary or not especially if you are in the turbo class.. remember they need to rev down also which also creates wear. These engines just don't seem to be designed to Idle for long periods of time ,,, They like large volumes of air lots of fuel and they like to work, not a good combination for idling. Just my opinion
Old 12-14-10, 09:53 PM
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this is a good read...i heard its good to burn some carbon off too, but i had a question...if the car is old, say 86 n/a and has never been rebuilt(yet) w 150k orig miles....i heard of a case to where the carbon build up were the only thing holding apex seals in and the lack of carbon was feared to knock the seals loose? plus i think that much stress would be risky if not had a major tune up first...right? idk maybe just paranoid bout it....id like to redline or close to it here n there but im not quite ready for a rebuild so i think i might stay cautious aroud 4 - 4.5k rpms for now...
Old 12-15-10, 12:58 AM
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carbon isn't what holds in the apex seals. carbon build up will make them stick and not work properly. wind that sucker up. once u do it the first time, it becomes easier there after, ur just paranoid.
Old 12-15-10, 06:02 PM
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alright ill try it a couple times, but im gona drive cross country first where i know i gota warm garage to work in if i happen to break anything...gettin ready for a rebuild soon n e way...thanks
Old 12-15-10, 08:01 PM
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WA Letting your Rx-7 Sit for more than a week

Adding on to the fact that Rx-7's don't like to idle, I heard that it is BAD to let your Rx-7 sit for a week or more, without driving it at least once a week. Is that true?
Old 12-16-10, 12:30 AM
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nah, it's when they sit for months at a time without being started is when apex seals start sticking and cause low compression/problems starting from a combination of high miles, weak seal springs, and carbon build up. now this is what i've experienced, others may have a different view.
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