4-rotor anyone
11-06-2006, 09:26 PM
#123
Senior Member
Join Date: Feb 2003
Location: Iowa Baby....Oh-Yea
Posts: 212
I only plan on reving it to 8500 or so, but check out what I found on winkipedia when searching for the 787B
"One engineer stated that the car could develop more than 930hp with a redline around 10,500rpm."
Too bad it wouldnt last very long..
"One engineer stated that the car could develop more than 930hp with a redline around 10,500rpm."
Too bad it wouldnt last very long..
11-11-2006, 12:01 PM
#124
Senior Member
Join Date: Nov 2001
Posts: 2,284
It looks like the 12A is back on. He just needed some gentle reminding that 12A stuff is the best way to go for this particular project.
We also discussed exhaust and came up with a potenially great sounding system based on my original idea of running two single pipe systems side by side and joining them at the rear end. They'll be equal length short primary systems flowing into a presilencer each then joining together and into an NA free flow muffler.
It's my educated guess that blending each 180° pair of rotors (1 and 2, 3 and 4) with 1.8 inch Racing Beat header pipes into two seperate runners, each with its own presilencer, won't hurt flow but will provide adequate quieting by accoustically canceling out the noise produced by the exhaust ports but without slowing velocity. It's like the Racing Beat single pipe system for 1st gens; except there will be two of them.
According to Racing Beat's info about p-ports, you're supposed to use 1.9 to 2.0 inch pipe and a short primary system is supposed to 10 to 18 inches in length (that's short compared to less extreme ports). Of course RB assumes you'll be reaching the outer limits of your engine's rev range. Talking 10k or higher. We only want up to 8000 with modest ports and stock apex seals for better street driving. And since it's based on 12A parts, I think we have a little fudge room in the exhaust system.
Oh, and in order to have the excellent 4 rotor exhaust note, as opposed to possibly sounding like two 12As reving together, the two runners will have to join together at some point. We're thinking near the rear end after the rearmost presilencer. We were thinking of firing it up without a muffler just to hear what a mostly unmuffled 4 rotor sounds like. Then maybe try an RB primaflow muffler since it's compatible and there's one on my friend's car, which we could take off and use temporarily. Sure it's restrictive for a p-port, but it's ok for temp use. That will give us enough time to figure out a better muffler. We have some ideas, and without a stock gas tank in the way, plenty of room to boot.
We also discussed exhaust and came up with a potenially great sounding system based on my original idea of running two single pipe systems side by side and joining them at the rear end. They'll be equal length short primary systems flowing into a presilencer each then joining together and into an NA free flow muffler.
It's my educated guess that blending each 180° pair of rotors (1 and 2, 3 and 4) with 1.8 inch Racing Beat header pipes into two seperate runners, each with its own presilencer, won't hurt flow but will provide adequate quieting by accoustically canceling out the noise produced by the exhaust ports but without slowing velocity. It's like the Racing Beat single pipe system for 1st gens; except there will be two of them.
According to Racing Beat's info about p-ports, you're supposed to use 1.9 to 2.0 inch pipe and a short primary system is supposed to 10 to 18 inches in length (that's short compared to less extreme ports). Of course RB assumes you'll be reaching the outer limits of your engine's rev range. Talking 10k or higher. We only want up to 8000 with modest ports and stock apex seals for better street driving. And since it's based on 12A parts, I think we have a little fudge room in the exhaust system.
Oh, and in order to have the excellent 4 rotor exhaust note, as opposed to possibly sounding like two 12As reving together, the two runners will have to join together at some point. We're thinking near the rear end after the rearmost presilencer. We were thinking of firing it up without a muffler just to hear what a mostly unmuffled 4 rotor sounds like.
