looks like people are already ripping them open. Curious to see the speedsource or yaw power ports for the rx8

 

Please tell me those ports werent done by a respected shop.

 

I stole the pic from the canadian sectino of the other rx7 forum. Which in term appears to have been stolen from the rx8 forum? I don't venture there so i'm not sure.

 

that pic was before it was done.



here's what it looked like cleaned up.



comments/critisism is welcome. maybe i can do it better next time.[attachment=29170:attachment]

 

correction: that's the other plate, but whatever...

the renesis doesn't leave you a whole lot of room to work with.

 

True. At the bottom of the exhaust port there is a great ridge before the sleeve so I guess you are limited unless you want to do some extreme mods. Those ports are all bordering on gigantic anyway. All you can really do is clean up casting flash.

 

WHY???



Why do they bother grinding into the "tip" of the teardrop?

 

i was hoping to see some better images

 

It looks like they opened it further out. This might keep the leading edge of the side seal from catching that corner. The stock edge in that corner is extremely sharp.

 

the auxilliary ports are opened just a little bit early (1-2mm), but other than that there wasn't any advance in intake port timing.



primaries were extended a little bit and there was a little back-filling, so the air didn't have to make a dead 90 into the combustion chamber. i'm usually a little sketchy on enlarging the primaries, but the dyno showed almost the same exact power until about 4k, when the ported engine took over. i think the important thing is we didn't lose power down low and put it up top...just conservative gains all around.



i saw a picture of a damaged side housing-where the side seal rammed into the sharp port closing edge of the secondary, so i made sure to give that area an oversized radius to prevent that from happening. leading edge of the side seal is supported everywhere else.



there's 2 basically dead 90's in the way of the exhaust path... since the water jacket is right there, there's not much that can be done except get rid of the sharp edges and try to radius and smooth it all out the best you can.



i'm in the process of testing an engine where the water jacket was welded up and the exhaust path is a LOT LOT straighter. depending on how it holds up, i may or may not do it that way again, or it might end up with some kind of uber-high temp coating.



any of the more experienced porters have any advice or questions?[attachment=29193:attachment]