Can someone please explain this port job better to me? I tried to do some research but everything that came up was the full Pport. I am thinking about doing a Semi-PPort 13B for my 85 GS.

Well, you were not supposed to know about this, because only really sick people would do this to a rotary.

But, if yoou promis not to do it, I will tell you how to do it.



First in the quest for more power you add the standard bridgeport. Then you get outrun a few times, and you go back in and do a big "J" Bridgeport, and that seems to work great, and one day a guy with a Pport engine outruns you, so you check on the price of some Pport housings. You wet your pants when you hear that price.



But the engine is apart already, so what to do?



Suppose that the "J" bridge port could be made bigger? The first problem would be that you would strike water. So we fill the whole water jacket next to the port with an aluminum filled epoxy. If there is no water there can be no water leaks can there?



So now you can use the epoxy as on wall of the runner and cut the housing part of the port further to the centerline of the housing, and the port is just huge. So you reassemble your new killer engine and go racing. You find that the added port volume has dropped your runner velocity so low that the engine only comes on hard above 8,000 RPM. Fun when you can get that far, but a general pig to drive in traffic.



So you take it apart again and make the port even bigger, but then fill in most of the side ports with a steel or iron filled epoxy and reshape the port to look like two small Pports side by side.



Now it drives pretty well, and the power comes on hard at 6,000 RPM. Now the guy with the factory Pport still outruns you but just by a hair, and when you show him your engine, it looks like a side port.



The down side beside the down time and porting is that it has to have solid one piece apex seals. Metal, carbon or ceramic, but one piece. There is no way to keep the end piece from falling into the Pport opening.



If you go to this port style first, and keep the closing line closer to stock, street driving is much improved. If turbocharged, it acts like a turbo Pport, yet better low speed drivability.



Compression seal grooves must be blocked next to the port as in the "J" bridge port.



Lynn E. Hanover

Well, you were not supposed to know about this, because only really sick people would do this to a rotary.

But, if yoou promis not to do it, I will tell you how to do it.



First in the quest for more power you add the standard bridgeport. Then you get outrun a few times, and you go back in and do a big "J" Bridgeport, and that seems to work great, and one day a guy with a Pport engine outruns you, so you check on the price of some Pport housings. You wet your pants when you hear that price.



But the engine is apart already, so what to do?



Suppose that the "J" bridge port could be made bigger? The first problem would be that you would strike water. So we fill the whole water jacket next to the port with an aluminum filled epoxy. If there is no water there can be no water leaks can there?



So now you can use the epoxy as on wall of the runner and cut the housing part of the port further to the centerline of the housing, and the port is just huge. So you reassemble your new killer engine and go racing. You find that the added port volume has dropped your runner velocity so low that the engine only comes on hard above 8,000 RPM. Fun when you can get that far, but a general pig to drive in traffic.



So you take it apart again and make the port even bigger, but then fill in most of the side ports with a steel or iron filled epoxy and reshape the port to look like two small Pports side by side.



Now it drives pretty well, and the power comes on hard at 6,000 RPM. Now the guy with the factory Pport still outruns you but just by a hair, and when you show him your engine, it looks like a side port.



The down side beside the down time and porting is that it has to have solid one piece apex seals. Metal, carbon or ceramic, but one piece. There is no way to keep the end piece from falling into the Pport opening.



If you go to this port style first, and keep the closing line closer to stock, street driving is much improved. If turbocharged, it acts like a turbo Pport, yet better low speed drivability.



Compression seal grooves must be blocked next to the port as in the "J" bridge port.



Lynn E. Hanover

Mr. Hanover,

I think he was thinking more in the lines of this port.

Nothing "Semi" about that. It is a tiny Pport.



Lynn E. Hanover

Lynn



Do you have any pictures of what you are describing. I think my mind pictures it correctly, but nothing like seeing the real thing. Thank you in advance.

Brad

The "semi p-port" Mr Hannover is describing is a bridgeport that has been extended very far into the rotor housing, but still uses the sideports inlet.



To imagine this using the picture above- delete the little round peripheral port in the rotor housing from the picture entirely, extend the bridge port (the one that is cut into both the rotor and side housing) toward where the little round peripheral port was and finally fill in some of that stock side port (the one entirely cut into the side housing).



The port pictured is a variation of a type refered to as a "cross port" in Japanese and was first used by Mazda in their very first rotary car the Cosmo Sport, but abandoned in the production versions.



The cross port is still very popular in Japan! I was looking through a Japanese RX-7 magazine and there were many companies selling manifolds and rotor housings in several variations and combinations to convert to cross port.



Some used the Mazda Factory peripheral port rotor housings and custom cast lower intake manifold to convert to stock primary port, peripheral secondary port and a blocked off stock secondary side port.



Others used a custom peripheral port rotor housing (very much like the one pictured) and a custom lower intake manifold so that the stock primary and secondary sideports were used as well as the new small peripheral port. This combination looked stock to all but the keenest eyes.

I agree with Blue TII, I remember reading an old HyperRev RX-7 Magazine that had the "cross port" in it.

I think the old Scoot Time Attack car had the hybrid peripheral/side intake port combo.



I will try to find it and post a picture of it.



Erik



https://www.nopistons.com/forums/pub...#>/bowdown.gif Lynn: I am amazed at the amount of knowledge that you bestow on us!

I have no such pictures, however I can draw up one in MS Paint.





Lynn E. Hanover

That port work is what most people call a "semi-Pport". Almost all the low seven second cars from Puerto Rico are running that port. It is a tiny Pport but you have to remember that all the side ports are also utilized and as with that picture the side ports are also bridgeported. This style of porting combined with a Borg Warner S400 80mm turbo are producing well close to 1000rwhp. http://www.ausrotary.com/viewtopic.php?t=46604 If you follow this link and look at the top 10 worlds fastest 13b powered cars almost all those in that list are running a "semi-Pport". Out of the top ten list only one car is not from Puerto Rico and that would be Abel Ibarra. Here some shots of the semi-Pport manifold.

http://www.mazdarotary.net/porting.htm Look at the J or Monster Port and that is what Mr. Hanover is trying to describe.

Somewhere I have seen a rotor housing w/ 2 small PP that utilizes the side ports for intake, but they have been filled to flow into the rotor housing instead. I know it sounds crazy, but I believe the port was to get around some racing rules. I'll look for the picture.

It's called a side fed PP. Was very popular back in the day when the rules did not allow PP>https://www.nopistons.com/forums/pub...1047683785.gif



http://img307.imageshack.us/img307/8265/sidepp2pr4.jpg



Go to this thread for some interesting NA setups. -->



http://www.ausrotary.com/viewtopic.php?t=115759

Thank you Crispeed. That is what I thought Lynn was describing.

Here is a picture.



If the port is used for a turbo engine, all openings may be left open. For a NA engine, the original (stock port may be filled with epoxy so as to maintain some velocity.





Lynn E.Hanover

Thank you for taking the time to work that up.

Well, thank you for that.



Lynn E. Hanover



Making the complex simple, for 60 years.



I have Al Gore style carbon offsets available in every price range,

for anyone stupid enough to buy them.

How can you seal it up between the tention bolt holes? RTV?

It seems like coolant would seep into the new runner.

Like here..

Lynn, your knowledge and moreover, your experiences, never cease to amaze me. thank you.

http://cart.chocolatesonline.com/ima...wnNose_400.jpg



You guys make me sick https://www.nopistons.com/forums/pub...DIR

It would seem that entire water jacket area would have to bee filled in on all the plates.

How does that stop the coolant from seeping in? Each coolant passage isnt sealed independently.



I think its a pretty cool port minus the potential sealing issue.

Better to have a brown nose than a brown ****!http://www.wirelink.com/poultry/pics/poult016.jpg

Brown nosing is not the same as giving respect.



Give respect where it is due.



Anyone with experience that is willing to share it with the rest of us should be given the utmost respect!



Erik

Maybe I should say I didn't mean anything by that before someone takes offence. My hat's off to Lynn here too, it almost seems wrong to read some of his posts without having to pay for info like that - but I still find it funny to read some of the comments (Lynns included) - maybe it's an American thing?? But lets forget about this and keep it on topic.



BTW touche ronin!

Rock on!



Erik

RTV is just fine. There is no water directly involved as the rotor housing is filled with Epoxy before you start.



The port is cut into the runner on the iron and there is no water in the runner face. In some irons there will be gaps where the face of the epoxy will have nothing to seal against, and in those cases a bit of epoxy may be needed on the iron, but this is rare.



Lynn E. Hanover





Al Gore's Gulfstream 5 burns more fuel in an hour than you and all of your friends do in a week. He sells himself and his friends carbon equivalents from a company he owns. So that they can say we do our part, and you, the bleeting masses, do nothing but consume fuel and generate greenhouse gasses.



When there are no longer cars, there will be Al Gore and his friends, and the world will be safe for Gulfstream 5s.



I hereby grant to you unlimited carbon equivalents to do with as you wish. For true believers, that includes tire smoke and full throttle operation of any combustion engine, if even for personal gratification.



In exchange (as Al would say) instead of collecting money from you, I will just think of some great ideas for saving energy, and saving gullible people from al gore and his friends.

thats kinda like having 8 kids and writing a book about overpopulation....



al looks at his power bill.....

Search: Manbearpig

man i posted this and forgot all about it. Yea the small Pport with porting on the side plates is what I was talking about. I have heard of people doing street ported, half bridged, full bridged and J bridged. I was thinking about going judge ito street port and semi Pport housings to give my car good power but still keeeping it drivable on the streets if I have to use it as a DD later on down the road.

I've always wondered why nobody ever made a semi-p port. I just never saw any, but they've existed all the while.



What about putting S5 13B housings into a RENESIS, porting as described in here, and using 6 exhaust ports too? The header would be easy to make, starting with a RENESIS header.

I am getting ready to build my semi p-port and ran across this thread. I was thinking about how much of a pain it is to machine a piece of tubing that fit the exact size of the hole you just cut and then matching the contour of the inside of the rotor housing on the tubing. Why couldn't you fill the coolant passage completely with epoxy and then bore your port in the housing? You already have a flat place on the outside of the rotor housing for a gasket to seal against.

I wish I could get my hands on one of this , I have one like it but its not the semi-pp one . If you know where to get one let me know , where you found this pics from ?

Where do I get one of these?

KGparts.com





I have a pic of a semi pp LIM. But i dont know who makes it or where the pic is from.

Pwned by browser

Sweet set up even better with that stock lower for a stock look fool alot of ppl with that https://www.nopistons.com/forums/pub...#>/biggrin.gif , wish I could get my hand on something like this . Looked at KGparts they dont offer the semi-pp port for the s4 s5 only 3rd gen and cosmo https://www.nopistons.com/forums/pub..._DIR#>/sad.gif

Here you go, contact 559hp, he has one for a 13BT



http://www.rx7club.com/showthread.php?t=716256