88IntegraLS

This is a wild thread!

Von, it is cool that you took a chance to experiment with your own port design. It was a huge port but I agree with Mazdaspeed7 that it opens too late for its enormous duration. It is also rough. This is where the side seals must scrape past. Maybe your side seals got stuck on one of those sharp corners.

There is much to be said about intake velocity. It is important for reasons of fuel atomization and inertial supercharging, as well as the tournament effect (slinglig intake pulses between ports as the rotors open and close them). That giant port kills the inherent intake port velocity that stock / street ports have and probably caused the lack of power you had under 6000rpm.

So what is usable power? You eventually need to shift up. If you fall back into 7K rpm when upshifting and fall out of the power band, then what? Your port fails you if that happens.

Get some housings for cheap and make your own ports. But study first. There is so much to learn about the rotary intake system. It is completely beyond anything with pistons, unless we are talking two strokes. In one hour I made a decent street ported primary with a die grinder and dremel (special thanks to Jimmi325i for guidance):



So don't give up. And don't let that fool near your ports again! That was the worst port picture I have ever seen. They all say "bigger is better", but not like that!

Good luck

von

Good Info 88IntegraLS...Do you know any rotory porting , inertia , velocity whatever site ?

Once I study on that I will find out if the next port that I make will work. Otherwise Ill just wing it again.

One more thing. IF you feel around the surface area over the port were the corner seal slides you will see that its smooooth. How is a corner or side seal that glides over it going to contact the edge that inside the port and not on the surface ? Does the apex seal bend inward. If so it would be a pretty large bend . Just doesent seem physically possible.

And name calling is not cool but sarcasm and belitlment is ? **** I was just joking with the moron remark.

von

And thiers a difference between Constructive Critisism and Sarcasm !!!

Mazd7,hypt,jim, exc

Jimmy325i

Just to put some things into perspective here... I was introduced to rotaries by a really cool industrial tech teacher of mine in 8th grade. (Vernan Schwartzkopf you are missed. He died the summer of my Soph year of cancer) Well, he liked the rotary so he took it upon himself to spend a whole class period on them. He wanted to get a motor in so we could work on it but the school didn't have the money with all the briggs motors we fucked up.

Anyways... So I've known about the motor for half my life. I spent 2 months last summer before cracking the block to determine how to make the best all around motor that could go another 124K.

I looked at timing, durration, port shape, manifold interaction, exhaust port interaction and all associated issues with it, casting limitations of housings, longevity, and finally how can I keep it in the 20's for mileage?

I could probably get another 10 hp out of a 6 port by forgoing any fuel economy. Another 10-20 ontop of that by eliminating the 100K mile goal, and another 10 on top of that by making it peaky as ****. Pitch the intake manifold altogether and we could probably add another 10 to this little pile. What would you end up with? A motor that will possibly make it to the end of the track in one piece.

You need to know what you want out of the engine before you say "Oh I want 500 horse n/a." Von, You said that you don't care about longevity. So why the hell were you breaking it in? Any fool knows that you can take a motor out of the box and rev it to the moon and it will make power. You have to wait for the apex seals to seat in a rotary vs a boinger, but that happens in the first 100 miles or so. (guess it depends how much like shredded wheat your housings look like)

100rpm on the stock ports is probably possible. Remember, I have ports as big as your dead motor, (actually, bigger) and mine just hit 8K mi of life and is going strong.

Oh, and when I thought I knew everything there was to know about port design... I consulted an expert before even touching the irons with a scrub brush. He just happend to concur with my plans and gave me his blessing.


As per the swiss cheese port that I had previously mentioned to you. (not a personal design, I have never seen pics of it, but its been around longer than I have) A single hole will flow volumes more than multiple holes occupying the same volume. Air is a fluid. When you spray fluids you are more familiar with (such as water) through a cheese grater (funny, I hadn't thought this analogy through with the swiss cheese and the grater) You end up with water everywhere do you not? It bounces off the surface and some, but not much, goes through the holes. This is the same effect the swiss cheese port will have on the air. Some will make it through the holes, some will not and will cause hell for the rest of the air in the runner trying to make it to the chamber. (aka: turbulence)

I wrote all this for the benefit of anyone who actually wants to learn how to make a motor build power. Von, you have issues and you have some admirable qualities.

Your "godzilla" port sucks. A little late to keep defending it. You obviously had intended it to last much longer than it did, or you wouldn't be here trying to find out why she popped.

However, You should keep trying. Persistence is a very admirable quality.

88IntegraLS

Von,

Go to the web forum that is named in Mazdaspeed7's avatar text and go to the rotary engine building and porting thread. It is pinned (sticky) so it is at the top. Judge Ito and other experienced builders talk in detail about port shapes and how they make the engine have certain characteristics, like broad power band vs. peaky power band, low end torque vs. even "pull" right up to the redline (which my stock ports certainly did not have )

There was another source I found online but I can't remember the url. I also read the book _mazda rx-7 performance handbook_ which covers everything related to hopping up the RX-7; ie. porting, intake and exhaust, suspension, and not just items to bolt in but how it all affects each other to build a car toward a certain goal.

The goal of my project is a semi-quiet streetable, semi-harsh suspension but low 14 sec. na daily driver that is a very competitive auto-x machine and still has the full interior. Your goal looks like it was a no holds barred 13 sec NA by virture of a street port taken to the limit of the corner seals, oil seals, and water jacket. I would recommend a bridge port myself, but to each his own.

mazdaspeed7

Some mod keeps editing all of my ****. First my sig, which I could somewhat understand, considering the **** administration here, but the avatar text is just uncalled for, as is blocking the name of a competing rx7 forum. If you type n0pistons.com correctly, it wont show up in your post. 88IntegraLS referred to the forum(n0pistons.com) that *used* to be in my avatar text as having a great thread on rotary building and porting. It does, and its really worth reading. Hell, they have a whole forum on building and porting rotaries, with a few very experienced and smart people there. Von, you should post a pic of your port over there, and see what they have to say about it, since my opinion, as well as everyone else on this thread doesnt matter to you, since you know everything, and we know nothing, even though our motors ARE running strong still, after thousands of miles.

mazdaspeed7

I tried to fix my avatar, and it wont even let me put n0pistons.com anymore. Bastards.

Jimmy325i

That is really dumb. This site has no membership, no store it is a function of, and no buisness censoring content in relation to other sites which have a meaningful relation to the common good. I could see if it were HotHSGirlsAssNekked.com or some ****, but nopistons? Whomever it is that is doing this to Mazdaspeed's stuff needs to either reply here or PM me. I want some answers!

von

Ya really...

I was going to bridge but didnt seem like their was room to on the 6port housings. I might scrap them for turbo housings or try a mild streetport on the 6ports and go from thier. If my N/A was already 14.5 in the 1/4 then im sure a mild port and carb will take me to the 13s for sure.

RX-7Impreza

Von,

i wasnt saying that you need clearanced rotors or hardened stationary gears, or any of the other intelligent things to run your car, with your port the way it is.

I was saying that your powerband is so far out of range for the components you have used that you have hurt performance more than helped it, with a powerband starting at 8k (we'll say 7k to be generous) and a rev limiter at 9k, you have 2 grand of power. i would like to see your track slip with 2 k of useable power. certainly not anywhere near 14's, and probably a LOT slower than stock.

and dont tell me that you were gonna change your computer to handle it, because your components WILL explode at over 10.5 k. maybe not your clutch, but something will.

too much research and experimentation has been done to prove this and your 5 seconds of redline isnt about to debunk it

Justin

yearrgh

This is by far the most screwed up thread I have ever suffered to read. What the hell is wrong with all you people? Von tries something, a little crazy, and maybe the port could be a little smoother, etc. and you jump all over him to assert your superiority when it fails. Even though I know that if this had worked, everyone of you talking down to him would be the first to say "Yeah, I thought of that a long time ago, I just never got around to doing it." And I don't think I've seen most of you be helpfull to anyone at all. You're the dicks that flame poor noobs for asking noob questions, instead of using your "vast and superior knowledge" that you seem to think you have to help people. All you do is flame people and talk down to them. You'll notice that the people trying to be helpful, like sonic rat, abandoned this post rather quickly. After about halfway down the second page it becomes dominated by people who I've rarely seen do anything but bitch and talk down to people.

As far as him not engineering it or planning carefully and doing calculations, theres nothing wrong with flying by the seat of your pants. If you calculate things and take a mathimatical approach, you can only achieve what you and everyone else already knows is possible. If instead you do something ballsy that you think just might work, you might have a failure, or you could discover something completly unexpected, that all the conservative calculation types never thought was possible. I'm sure everyone is aware that it was mathamatically calculated that a heavier than air vehicle could never fly. Someone had the ***** to try and what do you know, it worked. Not once have I seen Von say this port was anything different than an experiment that might or might not work.

Then to top it all off, after Von keeps excellent control of his temper while being subjected to one of the worst gang-rapes I've seen, Rx7 ragtop gives HIM a warning for calling someone a moron. What about the jackasses who have done nothing but talk down to him, insult his intelligence, without any reason for doing so. He did this to HIS car. He isn't suggesting anyone else do it, or saying that it's safe. He did an experiment, it failed, and he's looking for constructive opinions from others. Crap like this is why Dave left the forum. It's disgusting.

von

Amen.

All great people will eventually leave the forum. I think I will to and keep the rest of my findings to myself as others mentioned have. I know one guy E-Prod 7 who seems to be the smartest guy ive talked to who doesent even bother revealing his secrets or how much power he has made with his E-Prod race car to the forum , and he says its because of the same critism yearrgh mentioned

Rx7Imprezza ! Yearrgh is right. And although what you guys claim about the theory of ports you also dont know about the opisite. I can tell you that with a blown engine running 1.5 1.5 4.0 compression that I was still alot faster than stock with this port desing even though it was only to 9k...Sorta like when everyone on this forum told me that headers wouldnt do anything but a couple HP mabey even lose some over stock manifold streight pipe exaust. I did before and after dyno results and showed a max of 13rwp gain / 8rwp at the least. After I posted it nobody who told me otherwise even replied back to it. Funny..I disproved alot of things that defy logic...Like when I took out my sleeves and rods and j/b welded cut shaved pineaple sleeves in actually gave more power down low then stock especially with them just wired open. Although the conscesious of physics is that with scavenging and velocity the power would suffer but didnt at all. if it did it was like 5rwp under 1k. Things like that...Or like a 12lb flywheel makes your idle jumpy...I had a perfect 800rpm idle +- 30rpm acording to S-AFC and had no change before / after.
What about when I was told that porting the intake would do nothing? and if I ported it in an egg shape between the lower and VDI manifold that I would get horrible mid range? Dood im making more mid range than 90% of people on the forum and the curve is so flat and streight it looks fake.

Thnx yearrgh and everyone else who ansered my ?s...The thread served its purpose and I hope it dies lol...

Jimmy325i

Quoting von in another of his threads. "Yup , the first 2nd gen to have mid 13s (soposevly) with time slips and dyno results just blew up so im retiring to go to colledge and selling the car. "

Hummm.... You never made the dyno run or the passes at the track. I have yet to make the dyno run or run at the track, but when I do, I will have still beaten you.

You bitch about others being cocky and not helpful, yet you blew me off when before you destroyed these irons I had offered you another idea which could have proven very successful, in favor of this design. Now that you've shown the world what it was we all agree its shitty. And you take offense to this. Look around... People who do dumb things get harassed. So don't do dumb things.

Da Vinci came up with some wild ideas. As an artist he took liberties many cannot afford, however, he backed them up with physics, and years after his death others perfected those designs and made them work.

Notice that he wasn't the one who made them work? He needed the outsiders help too, and he was/is considered much smarter than anyone who's EVER posted on this forum.

Crying about no one helping you is complete bullshit. Had you told me in depth about your porting design prior to mutilating those irons, I would have backed up the opinion why it was a bad idea before you ever had anyone cut anything. R&D people are all engineers for a reason. They don't just pull **** out of their asses and expect it to work on a whim.

YOU Von, dropped the ball here. Not us. Don't go pawning off this failure on the social attitudes of this or any other forum. This is the damn internet for pete's sake. We all deal with real people face to face all day long and we want to rip their heads off for being stupid. So, since that isn't socially acceptable behavior, we come here and let the gloves come off. If you want to be cuddled with and treated all nicey... Go to a damn strip club and pay some chick to talk sweet to you. Don't come crying about how your mommy doesn't love you and your motor broke to us and expect warm hugs to coddle you.

I've been treated worse than you have for my posting of ideas and outcomes, so don't say you're being picked on. This isn't the damn 2nd grade and the teacher will not rescue you here. (even in 2nd grade you got bad grades when you screwed up) This motor gets an F for one reason alone. Regardless of how shitty the work was, it still didn't run long enough to prove or disprove anything. You have no dyno runs of this car and you have nothing to say it made more than 100rwhp, which is roughly what stock is good for. Big ******* deal.

You said you were retiring from rotaries. So stop whining here.

NZConvertible

He didn't try something crazy, he tried something that has been proven unsuccessful before, with a few more mistakes thrown in on top. And since when is correcting someone or pointing out their mistakes "asserting superiority"? This forum is supposed to be about sharing information and getting feedback. Are we not allowed to give answers that aren't exactly what the poster wanted to hear? And the fact that he's being critisised after the failure is irrelevent. If he'd posted a diagram of his intended design before commencing, he would've received the same advice. Von broke the forum rules by flaming, it's as simple as that. No-one in this thread has called him any names or broke any other rules. As for being gang-raped, when a bunch of more knowledgeable people tell you you've made a mistake, you should at least listen to what they're saying instead of getting all upset. If you can't hack that, then why bother posting at all? That doesn't make the critisism he's received any less valid. His supposedly experienced mechanic broke some long established porting rules like porting past the corner seal track. He claims no internal mods are required to relaibly pull very high rpm, despite that fact the race engine builders discovered they were necessary a long time ago. He's been given plenty of constructive critism, but refuses to believe any of it and decides we're all morons because on-one will agree with him or support his ideas.

This thread has definitely reached its use-by date. Von has been given all the info he need, and whether he believes it is up to him.

mazdaspeed7

Very well put Jimmy and NZConvertible.

yearrgh

The problem isn't that the criticism isn't valid, some of it I strongly agree with. He shouldn't have ported past the corner seal track, which he already admitted if you bother to read his posts, and he should definately smooth the corners off it. As far as reliability, he has said repeatedly that he never planned for it to last very long. Pro racers make all the internal upgrades because they want and need their engines to last since they're beating the hell out of them for extended periods of time. A drag race is much shorter, and Von just wanted to get a couple of runs out of his, so it doesn't matter if it's not going to last. You say that he wont listen to you when he's pratically agreed with half of what you keep giving him crap for, and the other half isn't necessarily wrong, but it's completely irrelevent in this circumstance.

The problem, as I mentioned before, is everyones attitude. None of this has been constructive critism. Saying that whoever did the port is irresponsible or inexperienced, taking bets on how long this would last, or suggesting he JB weld the corner seal is not constructive. What would have been constructive would be to say that next time he should be more careful about invading the corner seal track, make it smoother, etc. Or give him a link to a thread or website or give him contact info on people who have tried this before so he could learn from their experiences on what makes a port of this size fail, and what makes it work well. Read rotarygods post if you aren't sure and need an example of what constructive criticism looks like.

How is he getting upset, he has said repeatedly that he doesn't really care what you think he just wants an anwser to his question, which despite all your vaunted knowledge and greater experience, you don't seem to have an anwser for. And he is listening, he has agreed with you on several points.

NZConvertable, like I said, all you are doing is trying to assert you superiority and talk down too people.

Why not just say, "The great NZConvertible has spoken. Now run along child I have no more time for you."

rotarygod

iTrader: (1)

This has gotten way off topic and out of control. Lets get back on topic here. It didn't work, period. Lets give him some constructive rather than destructive critisizm (or however you spell that).

Von: What intake manifold are you using? S4,S5,n/a,T-II??? What type of exhaust system are you using? Stock, long primary, short primary, duals, hybrid??? What transmission? Auto, stock 5 speed, race tranny??? Which ECU??? Stock, piggyback (S-AFC), Haltech etc....??? I can help you optimize around what you have with this information. What you have has a huge effect on how much you can do and have good results at. It is possible to have nice large ports that are reliable but slower than stock. If you had a peripheral port on a stock setup (intake, exhaust, ecu) your car would be slower. You get the idea. PM me for some details. Remember, all good ideas at some point start with failure and critisizm. Maybe it will work and maybe it won't. The main thing is that you learn from your mistakes and accomplishments and make adjustments accordingly. Good luck on your future ideas.

88IntegraLS

Hey Von, I have another crazy idea. Did you have any traction issues on the Nitto drag radials? Normal slicks might be an improvement if you ever find a set on Ebay with rims included that you could snag. If you were pulling 14.5 on stock ports you don't have much less to do to get into the 13's. A normal (good) streetport might do it. I have also seen bridgeported sixth ports done before but never heard of the track results. Again, there is tons of info on this at n0pistons.com in the engine building and porting section.

I am secretly hoping for 13.99 myself, but that is a big goal for a rookie drag racer. I think launching plays a big part.

NZConvertible

I come here to discuss technical matters, and can't really be bothered suger-coating my words just in case I offend somebody who's taking themself just a bit too seriously. If my attitude bothers you, then I'm sorry about that, but have a think about what Jimmy said about taking the gloves off. I just call it like I see it. Damn, why didn't I think of that? That has a nice "superior " ring to it...

My point was, all the technical information has been discussed, and all we're left doing is bickering. If you want to continue, go right ahead.

projekt

bicker, bicker