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Old 03-30-09, 03:06 PM
  #26  
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Originally Posted by WaachBack
Anyone able to state the advantages and disadvantages of a half-bridge/bridge over a streetport (running a GT40 size turbo)?
Well what one is it thats 3 very different ports.

There is someone in Hawaii there running one of my HB motors with HKS T71. You could talk to him if you like. ReTed is also over there hes tuned some of mine as well.
Old 07-04-09, 08:56 AM
  #27  
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Question about the side seal support

Man, your ports are very similar to mine:

https://www.rx7club.com/rotary-car-performance-77/porting-questions-849832/

I'm just wondering that what happens when the end of the side seals are not supported and fall into the port (it looks like both of our ports will likely do that)? Do you think this will cause the side seals to wear out pre-maturely?


Originally Posted by RXHEAVEN_WA
I thought I would post up some specifications of my Rice Racing street port timing, pics and measures both with std rotor and RR special custom rotor.

Stock Port V's RR Secondary Port


Stock Port V's RR Primary Port


Modified Exhaust Port


IO = Intake opens
IC = Intake closes
EO = Exhaust opens
EC = Exhaust closes

Primary and secondary Ports same on std Rotor
IO 15° ATDC
IC 67.5° ABDC
EO 78° BBDC
EC 60° ATDC


Primary and secondary Ports same on RR special Rotor
IO 22.5° BTDC
IC 75° ABDC
EO 78° BBDC
EC 60° ATDC

V's

Stock 13BREW
Primary

IO 45° ATDC
IC 50° ABDC
Secondary
IO 32° ATDC
IC 50° ABDC
Exhaust
EO 75° BBDC
EC 48° ATDC


**************************************
Here is a list of some port timing for other types.

Port Timing

IO = Intake opens
IC = Intake closes
EO = Exhaust opens
EC = Exhaust closes

US Model First Generation RX-7
IO 32° ATDC
IC 40° ABDC
EO 75° BBDC
EC 38° ATDC

European Model First Generation RX-7
IO 32° ATDC
IC 50° ABDC
EO 75° BBDC
EC 48° ATDC

First and Second Generation 6-Port 13B
Primary intake (Part throttle/cruise)
IO 32° ATDC
IC 40° ABDC
Secondary intake (Part to full throttle)
IO 32° ATDC
IC 30° ABDC
Auxiliary high speed ports (Full throttle above approximately 4000 rpm)
IO 45° ATDC
IC 70° ABDC
EO 71° BBDC
EC 48° ATDC

Second Gen Turbo 13B
IO 32° ATDC
IC 50° ABDC
EO 71° BBDC
EC 48° ATDC


Racing Beat "Street Port"
IO 25° ATDC
IC 60° ABDC
EO 84° BBDC
EC 48° ATDC

Racing Beat "J-Bridge Port"
IO 115° BTDC
IC 72° ABDC
EO 88° BBDC
EC 57° ATDC

Mazda Factory Peripheral Port
IO 86° BTDC
IC 75° ABDC
EO 73° BBDC
EC 65° ATDC




Power and BMEP curves for NA S-A bp, combination port S-C (partial pp, same as bp for comparison reasons), and peripheral port
On open racing exhaust systems
Old 07-05-09, 11:18 AM
  #28  
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Originally Posted by howard coleman
i have now deleted 28 posts and and edited 2 posts in this thread.

posts remaining have two similarities:

they contain content relating to.... PORTING. (title of thread)

and

they are not insulting/argumentative.

now that i have moderating power in this section the thread will stay on message.

if you want to talk porting ALL posters are welcome. if you want to insult someone take it outside.

porting is a very important aspect of rotary development and there are both many ways to skin the cat and there are differing objectives and as such differing port styles to achieve each.

so there's lots to discuss. get to it.

just don't come in here w a know it all attitude because no one knows it all.

all the crapola is now out of this thread and we will now conduct ourselves in a respectful manner.

howard coleman
I must say Howard that is refreshing....I agree with you a dicussion is great for the rotary development bashing is counter productive.
Old 07-10-09, 10:36 PM
  #29  
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lets keep this thread alive...im in the process of gathering info for my first rebuild/port job on a S4 13b im trying to decide what porting to go with for this motor, ill be putting all my current externals on this new motor when the current one blows..i just made 450whp on stock ports on the current engine with T04Z. I was told by my tuner/rotary builder that i should do a race port on the secondaries and a street port on the primaries, he suggested the pineapple racing templates..he then said not to port the exhaust ports because the factory ports are made in the specific narrow oval pattern to help the velocity of exhaust gases flowing out of the ports, he stated that porting huge exhaust ports or making the port more rounded slows the velocity down which makes the turbo very laggy, is this true? He did however say that i should take a slight bit off the edges of the port, the black area you see from the inside, which isnt much. And also what kind of intake ports would you pros recommend? id like to hear multiple opinions with detailed explanations. The car is a street driven car but not a daily driver and i drag race the car often, id like to keep a good mid range power band
Old 07-11-09, 09:34 AM
  #30  
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what exactly is the difference between a half bridge and full bridge? do both require the rotor housing to be notched/beveled at the bridge area? i love the sound of the bridge port but i dont want to lose all my low and mid end power.. from my understanding thats what happens, the bridge is only good for top end, but im not sure what RPM range that would be?
Old 08-04-09, 05:26 PM
  #31  
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i prefer to be a rotorfile. i pick up my grinder and port, test and see the results, the rest is just random bullshit and hypothesis.

how come i don't see any discussions about enlarging/shortening the port runners? they are the bottleneck in the system, not the port size.
Old 08-10-09, 10:27 PM
  #32  
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IceBlue, what pdf file is that...?
Old 08-10-09, 11:10 PM
  #33  
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TX center iron small porting?

Porting looks great BUT why do the center iron always smaller? I have seen many engine builders with small center iron ports? You can still port more if you what your doing.
pic below is a series 4 turbo 2 center iron, I will a take picture of a rew center iron I have ported later.[/SIZE]
Old 08-11-09, 01:25 AM
  #34  
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posting to subscribe and remind myself to READ MORE!
Old 08-11-09, 05:52 PM
  #35  
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wow, what a read! this is great information and I'm glad its cleaned up now. This should be stickied somewhere, probably the "new member" section to keep people from ruining their ports.lol.

I "inherited" a torn apart S4 T2 motor from my brother (missing the intercooler, turbo and turbo manifold mind you, will be switching to the S5 turbo and manifold). I am rebuilding and was considering porting it mildly as its my summer daily driver. so I am wondering what kind of porting to do. I am planning on upgrading the turbo system in the future but my HP goal is only going to be 300-350rwhp.

This is my first rebuild and first port job so what do you guys recommend? and can I do a port based on my 300-350rwhp goal to run on my stock T2 for now or would I have to wait and port it with the final setup? more importantly, is it worth porting at all for the HP goal?

thanks, I heard the pineapple racing tamplates were good and they seem to know a lot but what are your opinions/suggestions for porting tamplates?

(EDIT: Mods, if I need to make a new thread for this instead of posting it here, feel free to delete this post. just thought I'd ask the guys that know what they're doing. )
Old 08-11-09, 10:47 PM
  #36  
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The reason people don't over port the primary ports is that's what HELPS keep a steady idle.
Old 08-12-09, 12:54 AM
  #37  
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steady idle?

Originally Posted by mono4lamar
The reason people don't over port the primary ports is that's what HELPS keep a steady idle.
First time I hear that one, Where did you hear that?
Old 08-12-09, 01:46 AM
  #38  
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Originally Posted by rotorholic
First time I hear that one, Where did you hear that?

Lets see a pic of the porting we saw at the Pan-Ams
Old 08-12-09, 03:11 AM
  #39  
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TX Atco porting on 100K rotary drag car...

Here you go...
Old 08-12-09, 06:44 AM
  #40  
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I believe Judge Ito himself turned me onto that. It makes perfect sense to me...
Old 08-12-09, 11:35 PM
  #41  
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I have a question of my own...

Is the factory tuned rotary the more fuel efficient and healthy way for the rotary engine, in terms of longevity?? Is it possible to tune/port the engine so that it can breathe better, become more fuel efficient and healthier...making it last longer? I'm not asking about increasing horsepower, just simply the goal of creating a healthier rotary engine with a longer lifespan?

Just out of curiosity.

Thanks!
Old 08-14-09, 01:25 AM
  #42  
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where can i get some rice racing templates???
Old 08-15-09, 06:12 PM
  #43  
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Originally Posted by howard coleman


as far as velocity.... very important NA. not very important when you are shoving 80 lbs/minute down the throat of a rotary. you have all the velocity you need courtesy of Mr. Garrett.


howard coleman
I asked this once to someone with a infinite amount of high boost knowledge. His low boost would be 100psi. His exact words were, "When I run a 100psi or 220psi I learned that the same principles applied." You still want the air in and out as fast as possible. You know, as I do, boost pressure is not a measure of flow, and more a measure of resistance. Our discussion came about because we were talking about plenum and end tank shape and how large a effect it actually has.
Old 08-17-09, 02:57 AM
  #44  
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OK, one thing i been wanting to do is make my own ports. i have always used templates. But how do i measure where i can and cannot port to?

I was told to lay either the front or rear plate down with the stat gear in place. and rotate the rotor around the gear. measure where the side seal and corner seal are and make sure at least half of the corner seal is still supported. but how do i measure and mark that if the corner seal and side seal are flat against the plate!?

any other way to do this?

can anyone enlighten me on this? using templates is getting old. im ready to step up to the next level and make my own ports...
Old 08-17-09, 10:38 AM
  #45  
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Originally Posted by sen2two
OK, one thing i been wanting to do is make my own ports. i have always used templates. But how do i measure where i can and cannot port to?

I was told to lay either the front or rear plate down with the stat gear in place. and rotate the rotor around the gear. measure where the side seal and corner seal are and make sure at least half of the corner seal is still supported. but how do i measure and mark that if the corner seal and side seal are flat against the plate!?

any other way to do this?

can anyone enlighten me on this? using templates is getting old. im ready to step up to the next level and make my own ports...
Cut an old rotor at the side seal to corner seal junction. You can then scribe the orbits of the ends of the side seals.

The thumbnail below is from nopistons' Lynn Hanover.

Note: only one end is scribed in this example.

Barry
Attached Thumbnails Porting-porting-tool-lynn-hanover.jpg  
Old 08-17-09, 02:19 PM
  #46  
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thanks...thats a damn good idea. I have a few dead rotors i could use too. but what to use to cut it? i doubt a saw zaw can cut through a rotor???
Old 08-17-09, 03:02 PM
  #47  
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Originally Posted by Zero R
I asked this once to someone with a infinite amount of high boost knowledge. His low boost would be 100psi. His exact words were, "When I run a 100psi or 220psi I learned that the same principles applied." You still want the air in and out as fast as possible. You know, as I do, boost pressure is not a measure of flow, and more a measure of resistance. Our discussion came about because we were talking about plenum and end tank shape and how large a effect it actually has.
just my to cents. I street ported my motor and now only have enough fuel for 12psi(95% injduty cycle). With stock ports I could run 15psi and would see duty cycles in the high 80's. the car is faster now using less boost and more fuel(ie less resistance to flow).

How does porting affect egt's and the same power level?? does a stock ported motor create more heat because it requires more pressure to make to same amount of power??
Old 08-17-09, 05:34 PM
  #48  
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Originally Posted by sen2two
thanks...thats a damn good idea. I have a few dead rotors i could use too. but what to use to cut it? i doubt a saw zaw can cut through a rotor???
I used a hack saw and then cleaned it up with a file.

Also you can use a Marks-a-Lot if you don't have Dykem.

Barry
Attached Thumbnails Porting-porting-2.jpg   Porting-porting-1.jpg  
Old 08-17-09, 09:47 PM
  #49  
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^thanks, appreciate that!
Old 08-17-09, 11:34 PM
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I have a question about Port filling.
I have heard often that the bowl volume in the stock ports is too large to begin with. Has anyone tried filling the bowl and provide a less angled entry to the combustion chamber by having material there to shape for a better skateboard ramp for the air? (so to speak)
I apologize about the grammar, but this idea has bothered me for some time. I've wanted to try it but haven't had my motor apart yet to figure out what I'd do as far as a plan of attack. Still figuring out what I'd use as a filler that I wouldn't be afraid would chip and cause damage.
Ideas?


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