xvampyrex

Hmm....so I would be able to achieve 200whp if I got my engine street ported with headers, exhaust and cold air intake?

RXciting

Don't see y not properly done.. a guy hit 186 with a small streetport exhaust and intake

Frank

IaMtHeRuThLeSs1

the problem w/ bridge porting is that, for the price/time you could have put a TII engine, and after the bridge port what next?...pretty much nothing, but w/ a TII you give yourself a lot more options...OR you could rip its soul out and put in a V-8 for a little more than a TII conversion.

DerangedHermit

Maybe you like the fact that your car is really fast AND n/a?

mythe7

ya. im gonna street port mine. im hoping for around 200rwhp out of my 87 base. right now: header, straight 2.25 pipe, k&n drop in. so far i havnt spent anything though . future: (above mods), safc II, medium sp, rebuild with s5 internals(already have them), 3mm or 2mm?(i have rotors cut for both), all the normal weight reduction things, pineapple sleeves.... more. but i dont remember what.

driftallcorners

^I think it's a tad more in depth than just bolting on turbo parts.

1RevvinFC3S

What about the Venom 400 Performance Control Module thing? Do they make it for FC's?

teezlr

So can you build a bad a** bridgeport and run like a 150 shot on it? That seems like a good setup.

casio

haha, i cant count the engines in here that would run like ****.
"oh yea, i'm gonna bridge it and the ecu will compensate perfectly."
in order to make proper gains, run well and be an overall great setup, youre going to need to replace the computer. most of the streetported n/as here have claimed mid 170rwhp. another person made 178 with stock ports, stock exhaust manifold, custom intake manifold and (here's the key) a haltech e6k. so this person made about the same as cars running full exhausts, minor (at least) porting work and possibly a piggyback. if you want an n/a to make power, its gonna cost you.
how reliable? well hopefully its built right and tuned right. cant much tune it without the proper ecu.
half bridges are streetable and idle fine. well, thats assuming you did everything else right.

a good setup for disaster.

200? i'd guess about 20-25 less than that. and there's no good reason to go 3mm on that engine.

Falcoms

They're not worth it IMHO. If you think about it (might wanna get a pop or something, this will get a little long...), the aux port sleaves open to a vaccum on a 6-port engine (unless turbo'ed, dur!). The aux port sleaves just slide in and "direct the F/A charge into the housing more efficiently." This line is total BS. All it does is REDUCE THE PORT SIZE!! Yes, folks, thats what I said, it makes your ports smaller. In essence, being that the port opens to a vaccum, the F/A mix will have more area to fill before entering the chamber without the sleaves. By adding the sleaves, even though they angle the charge in, there is less charge in the sleave as there would be if it was empty (stock). Imagine, if you will, the F/A charge. In the stock sleave, it fills the entire sleave and when the rotor passes, the charge is sucked out (rather crude description, but this is just the basics of what I am trying to explain). By adding the sleaves, the charge gets angled into the chamber, yes, but there is less F/A charge that is built up in the sleave before the rotor passes by, due to the reduced potential volume of the sleave due to the inserts.

Now, I will take a short breather...

Okay, now that I have explained that, lets talk forced induction on an N/A while keeping the aux ports working. Using the inserts would benifit the application DRAMATICALLY. The reason I say this is that now, instead of using vaccum to suck out the F/A charge, you are now forcing it into the chamber, so now you would want to direct it in more effectively. By directing it in more effectively, like the inserts do, you will force more F/A into the chamber through the aux ports while the ports are open, even a little bit, as compared to an FI 6-port with aux ports without the sleaves. The sleaves in this application would also distribute the F/A mix more effectively along the working chamber, allowing for more efficient burning of the F/A, ergo cleaner emissions (remember, only theory...I can dream can't I?)

Okay, so that is my short writeup on why NOT to use the aux port sleaves in an N/A application.

Aaron Cake

iTrader: (1)

Sounds good in theory, except for the fact that the ports close under vacuum, and open under pressure (from the exhaust in S4, air pump in S5).

I don't think you've ever seen these sleeves. They fill the "dead zone" at the end of the sleeve where the opening ends. There's a metal ridge of a few MM. You can clearly see this in the picture below. The end of the insert lines up with the port edge perfectly.





It's a lot more complicated then that. For one thing, you are totally forgetting that it is not a magical "sucking" from the rotor that pulls in the air, it is actually atmospheric pressure. The rotor creates a vacuum, and atmospheric pressure forces air in to fill the void. Now, with the stock sleeves in place, the air smashes into the end of the sleeve, and then has to roll back over itself to negotiate the little lip in the sleeve. The insert smooths that flow. Of course, this description is completely ignoring the pressure waves created by the air when the port closes, and the effects of the dynamic effect intake...

Making up BS is hard, isn't it?

Quite true.

I see that you don't understand how this whole system works...

Great.

Falcoms

I was talking the vaccum that exists in the rotor housing that pulls the F/A charge in, not the exhaust backpressure that opens the ports. Unless I am sadly mistaken, the pressure (vaccum) in the rotor housing on the intake stroke does not control the sleaves from opening/closing.



Okay, I won't argue with that. The dead zone is not very efficient where it is. No complaints so far

So, in essence, you are saying that the atmospheric pressure is pushing the charge in, not negative pressure (vaccum) pulling it in. This statement is absolutely true. What I am saying, though, is that the atmospheric pressure is going to be directed into the chamber by the lower pressure existing at that point in time, therefore optimizing the volume of the sleave (stock) as much as possible. The "dead zone" discussed earlier will throw a wrench in the plans for that air, though, being that it makes it much more turbulant before exiting the port (good thing in small ammounts to keep F/A mixed together, bad in large ammounts being that it would block said F/A mix from ever making it to the chamber).

Yes, good thing this isn't one of my usual school reports

I like it when we agree.

I don't know, I am just looking at it from the point of view that the aux ports are a much later closing time then the stock TII ports, and therefore the F/A coming from them is allowed to have a more straight shot towards the chamber in a lateral direction (across the face, pushing more F/A to the side without as much).

THERE WE GO!! ENTHUSIASM! I like it!

I won't lie, though. This is simply my opinion on it, based on what I've seen and what I know (which isn't much, in some cases). I am sure you have much more experiance, being that you did the whole N/A to turbo conversion, and you definately learned alot through that experiance. I hope we can still be friends, Aaron

digitalsolo

iTrader: (2)

Falcoms,

I think the problem Aaron had was that you said "here is why not to use them" instead of "here's MY OPINION on why you shouldn't use them"

On this forum, misinformation spreads like a California wildfire, therefore the Mods (Aaron and co.) try to fight it as much as possible.

Regardless, I see the reasoning behind your theory, correct or otherwise. The thing you need to remember, is that fluidity of motion is very critical in engine function (same reason that a smooth intake path will flow better then a rough one of the same volume.

88IntegraLS

Smooth = fast, and velocity = torque. Smoothing the ports, runners, and inner manifold surfaces will increase flow without decreasing velocity..... at least that's what veteran NA rotary builder / racer Dave Lemon of MAZDATRIX seems to think......

Shame this thread is limited to non-porting NA mods. Porting is the king of all rotary mods when forced induction is not an option, second only to exhaust. Here is my latest extend port street port. The car flies!

flamin-roids

I have the following mods on my S5 N/A.
8mm wires (not really a mod)
cone filter
light flywheel
2.5" straight exhaust to a single high flow can
Car runs great. Makes good even power. But here's what I've been considering.
half-bridge or large street port
new haltech ECU
bigger fuel pump (FD or TII)
bigger injectors (if mine aren't good up to 250hp)
port sleeves
3mm seals (just in case)
RB collected header
4.30 rear gears
Also lightening the car down by replacing the stock steel hood with a TII aluminum (roughly 30lb difference) swapping S4 TII wheels (on the car) for S5 TII wheels (8lbs lighter each) and pulling all A.C. crap out. My goal is to put down 220 rwhp in a 2500lb FC (car wieghs 2740lbs right now). Also if I could squeeze a 10k rpm redline that would be nice. Will it be faster than a slightly modded TII? Probably not but wil be 5 times cooler.

88IntegraLS

Although I hate to break it to all u NA guys, unless you do a full bridge or peripheral port with custom intake manifold, aftermarket ECU or some kind of race carb, 250+ rwhp is not really achievable......


..........without a little boost. Muahahahahahaha.......

flamin-roids

So how would corn flakes and toasted O's "boost" our power?

teezlr

or a little nitrous

Whizbang

who would think about doing that?


how much fuel can we expect to not have when he port? Kinda curious about doing it. Only i would be retarded and try to do it myself...

casio

now, might i ask, what computer are you running with those ports?

88IntegraLS

Stock ECU with SAFC. 550 secondaries are still too much fuel. That might change if I ever port out my intake manifold more and change the stock main cat and catback for something louder.

But if ur wondering, yep it pulls straight up to rev cut w/o much torque dropoff after 7k rpm. It peaks right at about 5k and holds to 7k, then falls off slightly.

casio

well thats very nice man. i'm sure that port with a new intake manifold (maybe without), a great exhaust and a standalone you'd be making some IMPRESSIVE numbers.
one thing confusing me; "550 sec's are still too much fuel." still? as opposed to? or was it supposed to be "still not enough" ??

88IntegraLS

I'm running -4% at 5k rpm and gradually going to -28% at 8k rpm for fuel correction. The stock 460's would have more than enough duty cycle to spray the fuel that my 550cc secondaries do at that correction level. So I guess they are not "too much" fuel when corrected, but would be if I didn't have the SAFC there to subtract some. There is a big difference in power between "too rich" and "barely rich". BIG difference. I've never heard a single ping and I've been on the lean side of things a few times. All it feels like is less power and gas pedal goes in really freely compared to when slightly rich.

ddub

Are we sharing porting pictures?




That's unfinished, though. I cleaned out the inside of it a bit more and then smoothed the transition for the sideseals on the end of the port. In all honesty I wish I had gone bigger. Integra's ports go further on the aux part, but being as that I have removed my sleeves and actuators and all and run it open all the time, I was concerned with driveability on the street, another reason I kept my primaries somewhat moderate too. But now that I've been driving this every day with an aluminum flywheel even, I find it is no big deal at all! I am seriously contemplating cracking the engine back open this summer and going extreme with the primaries and a bit further on the aux part of the secondaries. Who knows, maybe I'll even add my half bridge that I have planned out in my head If I were to do that, though, I'd switch to a Wolf standalone instead of the stock computer, I'm actually contemplating doing that sooner anyways.

For exhaust I did this!




I find that it isn't as pointless as a lot of people thing to port the exhaust on an n/a. Most people merely remove the diffuser and call it done, but I however did a streetport exhaust and then added the factory 2mm bevel to it. I can't wait till my break-in is over, this should make power much higher than before. This was also done because the turbo is right around the corner for me, so I figured I'd port it while it was out

If I were to do the extreme ports this summer, which I'm almost 90% sure I will be, and possibly the half bridge, I'll be redoing the exhaust port as well. Remove the sleeve completely and race port it/ceramic coat the inside for a humongous exhaust port. For those interested in where I got this idea, Mazdaspeed7 did this and has pictures over on nopistons.com and it is a work of art, makes me jealous almost That kind of exhaust porting will hold power extremely high, and that's what I may be looking for with future plans.


All in all, the N/A has a lot more potential than people give it, you just gotta be creative and willing to take risks

casio

holy crap, i didnt know you could do that with a stock 'puter! its so hard to get straight info, especially in the rotary porting world. how high have you revved it on that port? what mileage are you at? youve been in breakin awhile. you gotta be up to 5 or 6Krpm by now!
s4 or s5?