Does anyone know where I can find the process to build a peripheral ported motor, and pretty much everything that is needed to make it work?

 

I've been investigating this for a few weeks now. I have a friend and his father who will help me make the housings for free at a machine shop. The main problem I am having is finding out the correct size and location for the hole, which is crucial. Someone with peripheral ported 12a housings needs to help us out here. I know lots of people keep them secret due to motorsports competitions and such. Anyone have a junk properly peripheral ported 12a housing they want to sell me?

 

These are sold by Racing beat,sorry about the size.

 

This one was done by someone unknown to me.Note that its side,and perripheral intake.

Hope this helpes ? I have some info on the bearings and other things too,if your interested

 

Karism, thank you for the pics. Are those both pics of 12a's? I am interested in bearing info and anything else you wish to share.

 

Pleasure!I`am not sure if its 12a or 13B.

Let me make a short list of the things required(i hope my memory doesnt fail me..)

1.3 window bearings.
2.balanced rotating assembly (rotors,eccentric shaft,flywheel,counterweights)
3.Single piece carbon Apex seals.
4.110 psi oil pressure regulator
5.Hardened stasionary gears.
6.Lightened eccentric shaft and Rotors
7.Lightened flywheel.
8.Brass clutch,or Twin plate Tilton.
9.48 IDA Webber + Manifold.(normally with enlarged float bowl,and bored out to 51mm) / Microtech/Wolf3d Fuel injection system
10. Gen 1 electronic Dizzy,with locked advance plates.
11.open exhaust (2 " header with a 3 " or bigger pipe)

The bigger the exhaust,the less hp you will loose.

I dont mind to share what i have learned.

How much money are you planning to spend ?I`am sorry to say,but there isnt a cheap way out with perripherals....

They can cost up to 10k$....

A word of advice if your going to tune the carb yourself,fit a AFR...its worth every $ !!

 

This is a few links that will help you. I made these but since I used another racers design I cannot give you the location of where to put the hole. But you can contact Paul Yaw and he will probably help you on that.
He could give you reference points to make the measurement. If not then you have to setup a degree wheel. http://personal.riverusers.com/~yawpower/pic10.html
A word of advice is to read this entire thread before you get started https://www.rx7club.com/forum/showth...5&pagenumber=5 and look at Paul's site and especially the link to the pictures he has. http://personal.riverusers.com/~yawpower/

You could use a hole jig to make the 1/4" pilot hole and then the smooth shaft in the hole saw that this could be done on a drill press. The hole jig attaches on the exhaust studs and there is a 1/4" hole located at the center of where the tube will be.
You would still need to make the tubes on a lathe.
You will need to know or learn how to use a
https://www.rx7club.com/forum/showth...hreadid=144200

So this will require doing a little homework here but I can assure you that this is a lot more info than I started with.

 

oops!

 

Oops? More like thank you for the assistance! Maybe I could talk you in to cutting the holes and pressing in the pipes if I find the info on hole size and location I am searching for? It just looks as though you have done such a good job with things.

 

Well, the "oops" was because I had two threads opened up and I replied on this thread on a different topic.
I would have to charge about $250 a set to do them.

 

I just sent an email to Mr. Yaw. Hopefully he is willing to shed some further light on this. Thanks again!

 

I'm really curious as to how Paul bores his holes. The hole saw worked so good that I am sticking with it, but I do like to see how other people do things.
I ordered a Starrett carbide holesaw. When I cut the brand new housings my bi-metal hole saw bit the dust.
When I would cut the old housings it would go through pretty easy. The new was easy until it hit the nitrided surface. It was like hitting a brick wall.
I was lucky to finish Ken's housings because the last one took probably 15 minutes.
The carbide should not have any trouble especially using cutting oil.

 

I'll try to find out his hole cutting method while I'm at it and let you know.

 

Scalliwag isright about the hole,the location is important.I have seen some very different approaches to the location,everyone claims that their deishn works.

I think the Mazda Atlantica housings are a good indication.( Mazda factory race in America)

 

If you notice the pictures of Scott Yaw's and the ones I made for Ken Scheepers (from Jesus Padilla's original layout) are laid out like the Mazda factory style. The tubes go straight in parallel with the exhaust port.
This is in contrast with Racing Beat's design that are at an angle.
I point that out because Scott looked to be basing his design from the Mazda housing and his port timing is probably going to be based very close to them as well.
He has a page that gives the port timing and the Mazda pport is at the bottom of the list. That would be a starting point to figure out from there.

 

What would be the best apex seal for a PPort turbo motor i dont really know how well carbon seals would do and if steels can handel that high rpm

 

Just use stock Mazda

 

Really just use stock Mazda seals? I have been advised by most everyone I have asked to use carbon seals. When it is applied to a 12a you have to consider the stock seals are 3mm and 3mm seals have a tendency to "chatter" at high rpm. Even when using 2mm seals I would think the carbon to be a good idea since they seal so much better at higher rpm's. Now of course lower rpm range is another story.
I can't say I'm speaking from experience, just from what I have been told by numerous people. I'm open to all recommendations though.

 

I think the key point behind reccomending "stock Mazda" was the word "turbo". From what I've heard, the carbon apex seals are completely unsuitable for turbo applications.

Then again, this is all hearsay, so...

 

Oops, you are correct......I totally missed where he mentioned "turbo." For that application indeed use the stock seals. Carbon will in no way be a good choice!

 

I didn't have time to post the long answer and point out a couple of things when I answered his post. I caught the part about turbo and you guys probably saw the "high RPM" part of his question.
The slightly longer answer would have been to point out that he would want to run a lower RPM on a turbo and the carbons would break under boost.
The "best seal" argument has a tendency to wear me down pretty quick.
Fortunately his question was based with running a carbon in a turbo. The last thing I wanted to do was bring up Atkins, and Ianetti's, etc. which seems to get pissing matches going.
I would suggest that he tries the Mazda seals since they are readily available and decently priced. If they fail him he can try something else.
One thing that is for sure is if you start talking about turbo pport's you better not me too timid about going back into the motor at times. Unless you don't push it to it's limits you can plan on it.
There would not be much of a reason to build such a powerful and fuel inefficient motor if it was not going to be rode hard.
The drivetrain it would take to hold up to this power is something else to consider. A good streetport will eat plenty of output and half shafts on a regular enough basis to make you know the underside of the car better than you know the hood compartment. That has been the problem since the beginning of hot rods that people concentrate on making really bad *** motors and plugging them up to stock drivetrains and spend the next two years breaking and complaining even though they put stock parts back everytime they broke.

I believe the best way to go about it is to build a bullet proof 9" Ford rear even on a street car. You do that right one time and you will not have to touch it again unless you get in some serious horses and then you just put a spool in it. This is long enough so I won't even touch the tranny problems/solutions. Talk to Marcus (Turbostreetfighter) on remedying that problem.

 

i have a 350 in my daily beat rx7 now im building a pport motor for a drag car i work in a automotive machine shop for fueling ill be runing hillborn fuel injection the car already has a for 9" with a spool and a powerglide for a trans

 

i have pics of the jig i used on my bridge port if any 1 would like to see them

 

Hey, I wasn't intending to bring up the "best seal" argument. Was just saying that you most likely didn't reccomend carbons because of the boost unsuitability, which, as he said, he missed. Settle down, man.

 

Now I have posted several P-port videos' from Japan, both n/a and turbo, none of those motors seem to be high rpm screamers, they seem to have a shitload of midrange though, but from the tach in the videos' they are all shifting below 9000 rpm...Max