My exhaust ports what do you think
#1
Rotary Freak
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My exhaust ports what do you think
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#12
Banned. I got OWNED!!!
Originally Posted by Nihilanthic
whats the effect of radical exhaust porting on a rotary?
#15
moon ******
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Rice Racing - could ya run that by me again, I dont quite understand what you mean.
Do you mean it makes the torque peak larger so you have a bigger powerband to work with?
Also, does it effect low end or midrange at all?
Do you mean it makes the torque peak larger so you have a bigger powerband to work with?
Also, does it effect low end or midrange at all?
#16
Banned. I got OWNED!!!
Originally Posted by Nihilanthic
Rice Racing - could ya run that by me again, I dont quite understand what you mean.
Do you mean it makes the torque peak larger so you have a bigger powerband to work with?
Also, does it effect low end or midrange at all?
Do you mean it makes the torque peak larger so you have a bigger powerband to work with?
Also, does it effect low end or midrange at all?
My new engine combo has exactly the same porting, its as large as you can fit wihout the seals droping out or water leaking into the chamber, basicaly.... but this time running a more matched turbo and header combination to make full use of it.
#17
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Ah, so the same as porting anywhere else but without the drastic low-end drop.
BTW, why do you lose low end from porting out the EXHAUST anyway. Is it because of the earlier opening and not giving the expanding charge time to push the rotor all the way through the cycle as it would if it were unported?
I'm still a bit of a newbie and tryign to figure all this out :P
BTW, why do you lose low end from porting out the EXHAUST anyway. Is it because of the earlier opening and not giving the expanding charge time to push the rotor all the way through the cycle as it would if it were unported?
I'm still a bit of a newbie and tryign to figure all this out :P
#21
i am legendary
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He didn't do the porting, just for clarification here, so I don't think he has any idea about beveling the closing edge or why it's important. Nor would he probably be able to tell you much about removing the sleeves...
Sir Rupert Hobo bought the housings from SilverRotary, and he bought them from Rupert.
You know it's kinda lame to make a post about "your" exhaust ports acting as if you did the work when you really didn't.
And FYI, in stock form the closing edge of the exhaust port as a 2mm bevel for support as the apex seal travels over it, better transition. Once you port the exhaust these is taken away and must be added back.
https://www.rx7club.com/showthread.p...3&page=1&pp=15
https://www.rx7club.com/showthread.php?t=431210
Sir Rupert Hobo bought the housings from SilverRotary, and he bought them from Rupert.
You know it's kinda lame to make a post about "your" exhaust ports acting as if you did the work when you really didn't.
And FYI, in stock form the closing edge of the exhaust port as a 2mm bevel for support as the apex seal travels over it, better transition. Once you port the exhaust these is taken away and must be added back.
https://www.rx7club.com/showthread.p...3&page=1&pp=15
https://www.rx7club.com/showthread.php?t=431210
#22
Torqueless Wonder
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to put it simply: on a rotary when you port either exhuast or intake ports you will shift your powerband more to the right. which means you will have a peaky power band at around 6-8k. and the bigger you port the higer your revs are going to be because once you get to bridge-porting all your power will be at 7k or higher. and thats for street use. not to mention where the power goes when you "MONSTER PORT" or Peripheral Port. if i were you since you already have a massive exhaust go with a race port on the intake or "D-bridge" it with high compression rotors. or use 9:1 rotors with a T04S turbo. that should give you some good driveable power.
#23
Haven't we ALL heard this
Originally Posted by Turbo II-FB
what do you guys mean bevel the edges?? can you show pics
http://www.nopistons.com/forums/inde...howtopic=31895
James
#25
Hopeless Rotorhead
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They key tuning idea behind exhaust porting is overlap. The farther up you go, you give the engine more port overlap (where the intake and exhaust ports are open at the same time) so that the sweeping out of the exhaust gasses will draw in more air on the intake charge. These modifications can really only be utilized at high engine speeds when the rotor is moving fast enough and the manifold pressure is high enough to keep from pumping that fresh air back into the manifold. This is why ported engines make more power at the top end (much like aftermarket high duration cams in a piston engine) and also why they pull less vacuum.