jbontke

Well most of you know that when you install a free flowing exhaust on a 13B 6 port the other 2 ports don't open with out back pressure. Does anyone know how much back pressure it takes to open them? And do they open all at once or gradually? And at what RPM the begin to open and what RPM they are fully open?

Reason for asking is that I have seen some people use the air pump to open the other 2 ports. Can some one explain how they did this?

I was going to setup up a system that was servo actuated and the servo would be controlled by a MSD rpm activated switch that would allow you to dial in the RPM that it would open the ports. I know that when you change an engines peak HP area by altering the exhaust flow, you also change the points that the engine begins to make power. So by adjusting the ports RPM activation you could keep the torque up on the low end and have the ports open at the best RPM for the free flowing exhaust.

Another idea was to have them work off vaccum, much mile the vaccumm secondaries on a carb. As the engine load increased the vaccum secondary diaphram would slowly open the ports corresponding to engine load and give you a smooth port opening and not slam it open (causing a momentary lean condition in the engine) like the MSD operation would. I guess there is a spot on the 2 other ports that you could connect an arm to the diaphram and make it work. Also most vaccum secondary diaphrams are adjustable allowing the rate and RPM at which tey open to be adjusted.

Anyone tried this??

speckamp

Well, the aux ports work by positive pressure, not vac, so that won't work. I'd do a quickie search around some second gen sites, cuz I swear I saw a mod like this on one of the "second gen tech" sections of a site. Bascically you rig your airpump to open the aux ports via a solenoid and a rpm switch like you talked about.

The other alternative is to just take them out, and put block off plates over the actuator mounts. Sure, you'll lose a touch of low end, but you'll gain a little more top end (unless you're running pinapple racing 6p sleeves, then I'd suggest keeping them (or selling them to me))

--matt

Directfreak

iTrader: (2)

My original Idea was to have open up with Boost pressure from the Turbo Setup I was going to build.

Originally I was going to do a custom 6-port Turbo setup with actuactors opened up by boost.

I was going to place a small in-line solenoid so it would
open up slowly, and also not to push too much pressure to the actuators.

I believe they open at only 3lbs of pressure, and at approximately 3700 RPM. But I could REALLY be off, since I haven't seen my Haynes Manual in weeks.

Either way, when I opened up my "organ donor" engine, it was toasted inside, all the bearings where shot, and the housings where porrted too large for Turbo operations. (I'll post pics soon)

So That's why I am just going to get a J-Spec TII.
According to Crispeed, I should be able to make about 400-425 rwhp on a stock block, without even porting.
Also, those engines have significantly less miles that US-Spec versions.

So that will be my new route.

Sorry...
When it comes to Turbo First Gen's..
my mind wanders...

yayarx7

A stock port T2 with 400-425 hp? Is this with aftermarket Fuel system? Do you have to dowl the block to get that kind of boost? What turbo? I never heard of such a high power level on a stock port. Fill me in on your intended setup.

WackyRotary

Its rather simple to convert your port actuation to be off the air pump along on a '84-8813b 6port engine. This way the exhuast doesn't need to be at all restrictive. Their are many sites out there. Do a search on "6port actuation. The main things you need is a valve, and some heater hose and a conection of from the air pump to a adjustable valve. Somewhere in the line put a tiny hose that goes to the actuators. Then adjust the valve to allow the ports to open at 3600-4000rpm. Very easy, costs about 15bucks. Downside, your using the airpump, but sure its not draggin more then 1-2hp@8000rpm.

Directfreak

iTrader: (2)

Stock Port (91) J-Spec Engine (yes, dowl pinned)
Haltech E-6K
3rd Gen Intake Manifilold
Stock Primary Injectors
1600 cc Secondaries
Isuzu NPR Intercooler
Turbo Header (Divided Design by SFP, not stock manifold)
Turbo 60-1 compressor housing machined for a T-70(70mm) compressor wheel and on the turbine side a P-trim with a 1.0 divided housing
HKS wastegate
At about 15 lbs of boost.
TII Tranny
Dunno about the Rear end yet..

Note: I will NOT Run that much boost on the street, that will be strictly for 1/4 mile track times.

After all that..Mariah Widebody.

I will post detailed info online as I build it over the next few months. By the way my builder is Crispeed.

Max7

Just remove the actuators and sleeves and install Pinapple Racing Sleeves, you'll never miss the little bit of low end loss
and never worry again, "Are my 6 ports opening?"

Directfreak

iTrader: (2)

I thought the Pinapple Racing Sleeves are direct replacements for the stock ones (actually, they are modified stock ones).

I believe they open and close normally with the stock actuators, unless the owner deliberately removed the actuators or wired them open.

Pineapple Racing Sleeves

Max7

you can use them as stock replacments, or remove the center rod and locktite them in place

REVHED

If you're gonna pull the engine down for dowelling why wouldn't you port it at the same time. Doesn't make sense. Especially if you're aiming for those sort of power figures.

Directfreak

iTrader: (2)

I will look into it. I am was planning to use the stock block without opening it up. When it blows up (eventually) then I was going to port the **** out of it.

I will speak to my builder and have him decide.
I know you put more than 450hp out, doweling is really recommended. But remember, I don't plan to run that much boost regularly.

For street driving, the boost will be at about 11-12lbs, and HP will "only" be in the 350 range. Its gonna be hard not to kill myself with anything over 250hp on a first gen.

yayarx7

I still cannot see that kind of power with a stock port, even with those mods. but i am no expert and your engine builder should be so I digress.

But if you get 400 with those mods, a simple street port would probably boot you over 500, don't ya think?

Directfreak

iTrader: (2)

Engine Builder = Crispeed
His drag car is running 9.20's in the 1/4 and has *classified* horsepower. And that's un-tubbed with No traction.

I Hope so, but honestly I don't know. I am going by what he's told me can be done out of a stock 91'13BT.
I know you can get even more out of the 3rd Gen engines (Bigger stock Ports)

I know that he claimed that you CAN get that kind of horsepower of the stock port.

However, it may not necessarily be the setup that he is planning for me. I want a street car, so I don't need to run a HUGE Boosting/Slow Lagging unit in it either.

If the HP is not there, it will be damn close, he has a Dynojet in house to know for sure. Again, as the project continues, I will provide more details and post.

I am specifically going for a J-spec so I don't have to open up a good low-milage engine. Otherwise I'd just get a local 13BT, rebuild and port it.

peejay

what's so classified? 650whp at high boost/no spray, 692whp at lower boost/with spray. Of course, that's with a half-bridge engine, not a stock port

djs2571

I think the 3PSI is right, but the rpm depends on the engine load. Make another hole in the pre-cat or somewhere closer to the header...... move it up until you feel the other ports open. Or do it the hard way and put some pressure gauges on there so you can remotely monitor pressure in the pipe, see what happens.

itzweapon

the 6 ports.. with headders.. are useless... you will never notice the diffrence if they are removed.

jbontke

Can you elaborate? Are you saying when you add a header the 6 ports are usless(not reffering to the functionality of the other port opening)?

Directfreak

iTrader: (2)

That's incorrect. There are Special Headers/Exhaust systems for the 6 port engines.

They are designed with a small flange to still provide backpressure to actuate the 6 ports.

Check Racing Beat, Mazdatrix, or Mindtrain.

YOU WILL FEE THE DIFFERENCE..

itzweapon

I've never felt any diffrence by removing the 6 port acuators but then again I've not had a stock or normal aspirated Rotary in Many years.
I do know if the little tube that routes gases back to the 6 ports.. but we usally remove it and block the hole up.

WackyRotary

Does Pineapple racing fill part of the sleeves with a devcon or wield in it to conture it to get the extra flow characteristics with out the adrupt edges? How much do they charge for a set?
I don't see why anyone would wire them open when its fricken easy to just operate them with the air pump and a 5dollar adjustable valve from a manards? ..and its very, very reiable I had mine this way since I installed headers and intake and removed cat.

smnc

Here's the info...
http://www.pineappleracing.com/Prod-pr6pi.html

yayarx7

FYI the actuators are supposed to start to open at 1.8psi and finish opening at 2.7psi per the FSM

Montrealer

What I plan to do for this, considering i have no cats,

I can the hose that goes out to the cat, but keep the rubber fitting. to the rubber hose, I attach a "T" where one end goes to a pluming valve and the other goes to the six port actuators, by opening and closing the valve, I sould be able to ajust the rpm at wich the ports start to open, and all this for less than 10$.

Before i get this done, i got to take that snaped rusted bolt, that transfers the air from the tube into the lower intake manifold

yayarx7

thats how some of the 2nd gen guys do it, as I understand.