Twin rotor Peripheral port

[oldone]

Around 5k is the price after speaking to WGT for a P ported engine with all the right lightened toys.

Also the standard FD gears are not the best suited for a PP engine with the final drive being to high. Apparently close ratio gears are the best way forward on this.

Dont agree with the 5k but agree on the ratio side............... :Typing

[Grizzly]

Judge ito\'s car is a semi P/P engine of his own design I belive it was built for a Class of Drag racing which is NA.

http://video.google.com/videoplay?docid=2981005728491480378

There are lots of levels of P/P engine\'s, its possable to build one that has less overlap (brap) than a Bridge, There are a few old schoolers who run P/P Na engines in there road cars without much issue. When i was looking into it quite a number of people said tame P/P engines can be compaired to a small Half Bridge but a large P/P can be compaired to a Small Full Bridge (if set up correctly and has the correct timing). TBH i was more intrested in Building a Turbo\'d P/P (which is harder due to the Port timing) so i did\'nt realy look into the NA side of the P/P world too much.

[McCARTHY]

TBH if i was going for a full drag car then yes i agree a turbo would be the route i know of one FD running a 4 rotor twin turbo on a PP and thats making 1000bhp in Auz. I have a feeling its rebuilt an awful lot!!!

This will be just abit of fun when i do it. i have yet to find a suitable oldskool chassis worth gracing with this type of engine so its not an imetdiate thing at the moment.... and the FD needs a little TLC first too....

[Grizzly]

With any Big overlap engine the more Rotors you have the more behaved it will be, TBH i have only every been in one 2 rotor NA with Big P/P and that was a Track day car, was an Experiance (Just had two seats and a Cage and was LOUD!!!)

Turbo\'s don\'t mean it has to be a Drag car? I wa told to do a small P/P as high up the housing as poss then fit a Turbo, this way it would be alot easyer to drive on the road.

[McCARTHY]

easy to drive on the road!!!!!   thats no fun  :p

[stuart wizy]

5 k !!!!!!!!!!
does that come with solid gold rotors!
5k to bore 2 holes and turn 2 ali inserts and press the inserts in the housings!
If anyone needs exact procedure and tolerances to do a pp port
email me on stuart.wiezniak@ntlworld.com.
Ive got exact method to bore the housings , tolerances, centre point from bottom face etc etc.
The inserts are turned to more or less the same size as the bore, then frozen to shrink, then pressed in to the housing,and left to warm up and expand for an interference fit.
You could take your housings to any decent machine shop with this method for boring, and get the ali inserts turned to suit for a lot lot less than 5k man.
A very helpfull engine builder from aus was kind enough to share his usefull info on pp boring and turning so I will pass on this info to fellow members.

[McCARTHY]

+ individual throttle bodies, linkage, custom inlet manifolds, injetors, rails etc etc etc installed built rebuilt etc etc... In prob getting this engine done in Auz eitherway

[McCARTHY]

cheers for info buddy i\'ll drop you a line it would be very very helpful  :Thumbs-up

[stuart wizy]

with this method you can buy 2 tube bent throt bodies from racing beat or auz to bolt on the inserts that u get turned.
The ali insert has a face on the end that has 2 holes drilled through to bolt your throt bodies on.

[stuart wizy]

any decent turner and borers would p@ss these of mate , trust me!

[Grizzly]

How did you set the timing? my Turbo P/P\'s are not round? they are simalar to the exhaust port\'s shape.

A simple P/P are round and if your not to fuss\'d about the amount of overlap or getting the max out of your Comp stroke then you can just bore a big hole in the housing and put a tube in, This is mainly how Na\'s are done as the Port Timing is not as important.

Up until recently you could buy Genuine Mazda P/P housings (not sure if you still can??) and they where d shaped. I don\'t know alot about Porting but i am under the impresion all that extra work shaping the ports to a D will have some sort of benifit.

You also have to read up on Inlets and Throttle sizes, you have to also decide if you want a plenum or not? If i was you i\'d go and talk to some one who has run and tunned lots of difrent P/P setups and will know what you will need. You may not get a good power band buy drilling two P/P\'s and putting on a Manifold thats pre made to some one elses ports, the manifold may be for Drag racing and you want it for the Track?? or you want to get as much low end power from the P/P as poss but the manifold/Throttles are for Top end?

[stuart wizy]

They bore the hole breaking through the inside of the housing, then bore 6mm bigger leaving a step in the bottom of the bore for the insert to push up against , the wall thickness of the step face is 5mm on the thinest edge.
The insert is then pressed up against this step so the required port shape can pe ported out to whatever port shape on the inside of the housing just like porting out exahust ports.
The d shape seems to be popular for drag racing in aus.
ask the qusetion on ausrotary explaining what use you want out of the motor and what port shape to go for ie round or d.

[McCARTHY]

I\'ll post the spec\'s of the engine when they have been sorted properly.

[Ada7]

Any of you guys speak English on this thread  :rollin
Makes me realise how much i dont no about these engines. Should read up more i guess

Adam

[Grizzly]

This is a large NA P/P for those who don\'t know what we\'re talking about