You could make a very complex valve system that would measure the back pressure between the valve and the port and adjust it where you wanted it.
After seeing the telescopic throttle system that Mazda ran on that LeMans car in '91 I don't think this would be any more extreme than that !

 

Allright i will PM you again. It was a really long message and now i cant find it or anything so i am going to have to retype it but i will send it probably sometime today. I totally aggree with what you have to say about these engines, but i think the number one reason why they would not be the best choice for street use is totally because of the noise issue. However that can be "remedied" with a 40 inch long semi truck stack muffler they are still loud. So thats my take on it.

CJG

 

Very complex valve system... this reminds me of the 6-port actuators. *shrug* I was just figuring have it be triggered at a certain engine RPM.

 

6 port! Ouch! That hurt!
There is probably a way to have the back pressure "valve" adjust at an optimum rate for the RPM.
For all out drag racing, opening at a certain RPM would be good. But for road racing you would probably want to govern the valve differently. I would make for an interesting project.

 

Here is a picture of my custom 6 port peripheral manifold for s6 lower intake. The runners were cut and y'd to the 2 peripheral ports and utilizes the stock upper, very sneaky move. Rice Racing helped me with a few questions i had with the setup. I did run this setup on the street, drove fine, idled at 1100, little loud, but nothing that mufflers cant fix. It seemed to get better gas mileage than some streetported cars ive been in actually. Here you can see where the runners were added...

 

i am actually selling this manifold, let me know if anyone is interested... sorry i didnt clean it up for the pics, still has permatex on the face of the flange.

 

The pics are so dark it is hard to tell what it looks like.

 

Not really... you want to switch over (from a power standpoint) as soon as having the PPorts open would make more torque than just the side ports. And that's pretty much a constant. Besides, IMO, you'd want them to always open at the same point in road racing so you can predict how much power you're going to put to the wheels.

 

If it opened too quickly you might end up with an effect like the 3800 RPM dead spot on some of the 2nd gen's though.

 

Well... okay. I'm going to seperate this off into two thoughts, road racing and street driving.

Road racing: Really, you shouldn't be letting the engine get that far down in the powerband anyway. Bad dog.

Street driving: Weeeeel... I can't help but think that with a bit of EFI tuning you could compensate for it. If it's electronicially controlled, you know exactly when the changeover is going to occur and can do something about it. If you have it driven off of some system of valves from exhaust backpressure... well, it gets trickier.

Or hell, set it up in the computer to open them above a certain load level, as determined by MAP and throttle position. I just don't see why you'd want to go plumb it to the exhaust when we have lovely tools like computers that can control things more accurately.

 

I wasn't talking PP port. I was talking about the intake runners and twin throttle body setup. I don't have any plans on doing a PP on my car.

 

hey rice, I re typed my letter and sent it to you so let me know if you got it, other wise i could either re send it or just e mail it. Or e mail me, jaloy@tscnet.com

CJG

 

Rotortuner, I got it...check your PM

 

with all this talk about exotic partial peripheral ports and acuated valves, have you guys taken into consideration the exhaust port. it would seem to me to take full advantage of a pp, you'd need a huge exhaust port, prolly taking out the sleeve and completely hogging it out. now, it would seem having the sp for low end and pp for top end would be negated by the increased exhaust overlap. the exhaust wouldn't be tuned for low end power, so having a complex sp/pp wouldn't yeild much more low end than a full pp.

 

Yeah thought of that, but it would work on a side-exhaust rotary, because you could just switch from side-exhaust side intake to PP in PP out...

-pete

 

It looks stock other than the fact that their are 2 elbows welded into the secondary runners that run to small peripheral ports. You can see the new pp holes in the second picture.

I'd like to see that exhaust manifold...

 

Naa... Quickest NA Rotary in New Zealand is PP and idles at 1000rpm (20B mind you..).. he has since built a 4 rotor and hogged the ports out as big as possible.. idle now 1200rpm.
Thing keeps try to jump off the dyno and spins the wheels at 4000rpm so a power reading is yet to be established, but 179rwkw at 4000rpm can't be too bad for an atmo thats just about to come on the boil!

PPs aren't that difficult to get to idle at low rpm.. IDA carb setups tend to do it better.

BTW, the side ports don't HAVE to be filled, as its often a good idea to leave them open and run a blank plate where the manifold used to bolt to if you intend to play with turbos later and save the added expense of new plates.

 

Matt RC-Racing

Matt or-sam to here you have a 4 rotor engine running. Who has this fasted naturally asprated engine in NZ and what record does he hold??

Look forward to hearing good horse power readings from your 4 rotor engine,is this a race car or road car?

 

Unfortunatley the engine is not ine, but we will prob build one if it'll fit into the enginebay of the Ute..
I'm not giving any secrets ou, but you will see it at the Nats this WE.. its in a car thats been around for a while.

 

just to add a little more fuel to the PP streetable or not debate .... NSU R080 engines came with PP inlets as STANDARD

look no side ports

 

Damn Tripod! Don't you hate it when that happens? Find another site to host your files on MikeLMR
so this won't happen. I would love to see the picture.

 

right click it and and then cut and paste the address into the address bar ... I "borrowed" the pic off another website ... didn't realise it wouldn't work ... sorry

its not fantastic anyway

 

Matt RC-Racing

I havent heard any results from the weekend, how did your friends 4 rotor go? did he break a 10 sec quarter??

 

Neither...
I'm yet to hear from him.. havn't heard anythign yet..
Wonder if Reece put his GTR through the fence at the end at 150km/h again??

hehehe

 

Do us a favor and post it when you find out