y8s

iTrader: (8)

7% of the cost of your headwork says this Vizard dude will never even know you did anything. Start calling it something else like "mismatched valvelry" and he won't even be able to google it. H wont sue you for doing a one-off head that isn't for profit. If he even managed to know you did it or somehow contact you (pay cash?), then he has to send a cease and decist before he can outright sue you for infringement. I wouldn't lose sleep over it.

I'll help you:
1. Next person to type the words Vizard or Polyquad gets the hammer.

2. Google "experimental use exception patent infringement"

aidandj

iTrader: (5)

<p>...so tempting...I've never been banned before. Yet, I would be really bored at work.</p>

patsmx5

iTrader: (16)

This is good stuff. (haven't googled it, about to)

But what I know is, you can do whatever you want that's patented, so long as you are not doing it for profit. So I can do whatever I want to my car, I can find 50 patented ideas/processes/etc and use all of them on my personal car, and so long as I don't sell these things for profit, I'm legal. Is this right?

To Pontiac, nobody here cares about the legal crap, you brought that up. You may be right, but nobody cares at all about that.

On topic, I'm a little curious if ANYTHING we could do to enhance swirl would improve the knock-resistance of these engines? If we could reduce detonation, we can make more power as these motors are typically knock-limited at high boost on pump gas.

Pontiacivan

I agree with 1-4. This seems to be the " loophole" way to try this out.

But why 5 ? Please support your view. What law of air flow or physics or swirl and tumble or mixture homogenization do you believe breaks down ?

This is the honest and intelligent conversation I originally intended to have.

For instance, has it occurred to anyone else that , as you look into the intake port, the big valve would always have to be on the left side ? Same if you looked up the exhaust.

Pontiacivan

You are right, a not for profit job is free and clear. Machine shops in my area work on a strictly profit basis.

I also agree "He" would probably never know. Does this make it OK to ignore the law.?

"He" would actually sue the shop, not the customer, but I get your intent.

I really wouldn't lose sleep over it. If I had it done partially at one shop and partially at another I would sleep just fine. But money is money and paying for disassembly, machining, " environmental fees" ( whatever the heck those are) twice in a row at the average shops labor rate would suck. I happen to be a v8 owner, so double that fun. I have to look to my 4 an 6 cylinder DOHC brothers and sisters because the v8 DOHC world is weak. Throw a supercharger on it and forget everything else. Well.....I can't , so it's technology or nothing.Maybe I need to take a night class in machine work. Lol.

I do want to have a serious technical discussion on the " mismatched valvery " now that the name calling has been stopped. My thanks to the moderator.

The claims made are not small. Someone said 10WHP but the article claim 98 at the crank for a 4 cylinder. Ain't no way drive train losses equal 88. Lol. So what gives? Is it bunk or not? Why might you think so, one way or the other?

Pontiacivan

Absolutely correct on the not for profit angle. I have lots of those types of mods in my vehicles.
I am duly chastised on the legal issue and I repent. I get that it doesn't matter here. I was a computer tech back in the early 90's. Saw a guy get 5 years for bootlegging DOS4. Man was he embarrassed when he got out. Had a customer sued by RIAA for junior downloading gigs of music. I guess I am a little gun shy since I know it can actually happen.

Your " off topic question " might not be so off topic. The " idea" has a lot to do with swirl and swirl generally does increase knock resistance. Does ANYONE know of effective ways to increase swirl on a DOHC head design ? Cuz, I get why they don't seem real good at it. I have Pistons that are supposed to increase mixture rotation. I make 28whp more than stock, but a have cold air, a good tune and lightly modified exhaust so I can't say how much is from them.

Braineack

iTrader: (62)

too late, i just patented modifying the cylinder head in any way.

Joe Perez

iTrader: (8)

I've been ignoring this thread all day yesterday and most of today.

Only just now opened it up, realized it was old, and read from the point at which the bump occurred.

I now have a strong craving for baba ghanoush.

y8s

iTrader: (8)

Dammit, I didn't see the OP date.

What's babaganough made from again?

Savington

iTrader: (31)

Presumably it's made entirely from shitty threads like this one

Pontiacivan

Interestingly enough, even with my unpopular off topic opinion, I'm still the only one who wanted to actually discuss to performance potential off this mod in the " engine performance " forum. Still,willing to hear pros and cons. I'll start. Opening one large valve earlier than a second smaller valve will make the charge swirl. Not a thing any of us can do about cuz that's how physics works. We want swirl. We know we do. We look for wasys tomake it happen. So.... Somebody tell me why they think this won't help or why they think it will. Also, though the dual duration cam events were dismissed as minor in the original article, I think they need to be used in conjunction with the other mods. Maybe a stock or close to it profile on the small valve and the performance profile on the
Larger valves.

Joe Perez

iTrader: (8)

I posit the following, without have a strong opinion either for or against this idea:

We want swirl to make more power, because we believe it will increase knock resistance.

Achieving this by running less valve size and less valve duration than would otherwise be the case will decrease VE. All else being equal, that decreases power.

It's possible that we may be able to subsequently increase the timing advance enough to overcome this loss. It's possible that we may not.

In the NES video game Kid Icarus, there was a type of enemy character who, when encountered, imparted a curse upon the protagonist which hampered his mobility.

patsmx5

iTrader: (16)

Try it and see what happens. I'm not aware of anybody actually doing this on a miata, so I doubt you'll find any data. I personally would probably never try this, but if I someone DID try it and got results, then I'd be a lot more willing to try it myself. That's generally how testing ideas works, people aren't going to do it until someone else proves it's worth doing.

There are some people here that would rather talk ****, or have off-topic jokes, or try to troll you, or carry on their inside joke rather than contribute to what you're trying to discuss. That's just how it is, and you can't change that here. Despite these "distractions" this is still the best miata-technical forum I've found, so I just accept that's how it is around here.

patsmx5

iTrader: (16)

Agreed.

My thought would be to say, go up 1 or 2 mm on just one valve. And do the same porting/unshrouding for each valve. But if you went say +2 on your big valve, that could potentially induce a little bit of swirl. My lack of knowledge on this is hinting it wouldn't be enough though, I think what you wrote about changing the cam duration is probably what's required to get enough swirl to make it worthwhile.

Pontiacivan

Thanks for the honest reply. Because there is no easy VVT option for me, the dual duration, staggered valves may be as close as I get. As I mentioned earlier, I have Pistons designed to promote swirl and I picked up 28 WHP ( V8) but I had other mods as well. I come to the 4 & 6 cyl. Forums because you guys have been doing DOHC for a long time. I have applied lots of ideas that I picked up from listening.

I have never been a fan of "trick" spark plugs, especially in 2v wedge style heads but it seems like they might have some merit in a head design where there are centered. Any opinion ?

For the record, and I'm fine if nobody cares about my non Miata engine, I make 1.5 HP per cubic inch N/A, totally streetable and 11:1 on 92 pump gas with no knock on the data logger. I may have come off as a jerk when I started but I can for sure tune. Thanks.

aidandj

iTrader: (5)

<p></p><p>So on a Miata engine thats like 20hp more than stock 10:1 comp? Sounds like &quot;eh&quot; tuning to me.</p>

18psi

iTrader: (76)

1.5hp per .016L
so 150hp per 1.6L
so basically 20hp more than a bone stock miata? that runs 9.0:1 comp and is considered a slow turd, wheezing through restricitve oem components
and 35y/o engine design

*edit: aidan beat me to it lol

patsmx5

iTrader: (16)

He didn't say what motor, if it's a push rod 2-valve that's respectable power. Obviously for DOHC I4's that's basically stock, honda has bested that!

Pontiacivan

Man, you guys are brutal ! Lol. I am also running tech that was designed 35 years ago by a company that was another 10 behind the foreign market. It took forever for an American manufacturer to produce anything close to 410 real HP from 279 cubes, so I am not ashamed. Be fair, you guys only had to find 20 HP, the factory did all the hard work for you. I had to find 135. Oh, and I can pass a tractor trailer without turning over 2000. I don't want to measure junk here, I want to learn from you guys. Please, just give me a chance, I actually have something to offer. For instance: I looked at the post yesterday with dyno graph and the dip on the torque curve and I know what is wrong. I just don't think anybody would listen. Yes, some of it is VVT tuning and the dip will get " better" so the owner might stop there but they will still be down on the power they could make.

18psi

iTrader: (76)

enlighten us

be very specific. I'll be honest and tell you if you're right too