As the title says.

Secondary Shutter Valve Delete

To remove the SSV and bolt on a block off plate in place of it.

Pros- no air restrictions

Cons- check engine light?
(What if you left the sensor plugged in?)

Anyone else like to chime in on this idea?

 

Cons: terrible idle, fuel economy and ability to start. See "SSV stuck open" threads for more info.

Unless you plan to spend the car's entire life at high rpm, like a race car, there is no win in this.

Air restrictions are a good thing when you're trying to increase intake air speed rather than volume.

 

Short answer: Don't do it, and learn more about how engines work before you come up with something like this.

Long answer:


And you can even do your own experiment. Go grab a straw in McDonald's, then a big one from a bubble tea place. Try drinking while sucking on them with roughly the same amount of effort. The McDonald's straw will shoot the drink out faster than the Bubble tea straw. Same idea here.

 

/faceplam

 

I have already started the experiment by wiring it open (SSV) and the upper intake crossover butterfly valve has been wired closed.

So far I notice positive results. Throttle is more responsive and no break up around 4-5k rpms (which could be a failing SSV)- which is why I considered this idea. Also 13b's in FCs we always wired open or removed those intake canoes.

There is no issues with starting, in fact it starts quicker to me. No idle issues.

As for fuel mileage- I will have to calculate over this following week. Im due for a fuel up soon and then I will have somthing to start from to see. Except I didnt pay attention to what its current mpg was before hand lol - to me, the mpg is pointless in a car that im constantly racing and revving. You dont buy a sports car for fuel economy /facepalm

I understand the reasoning behind the design, but for trying to get more HP out of the engine with simple ideas is worth a shot.

If I find the no issues with this setup, I might leave permanently or remove and bolt a blockoff plate on, but as you know how SSV is, it might be better to leave it installed open than removing and leaving a big open chamber, at least with the SSV open theres a straight flow through the intake.

Any other ideas? Thanks for the responses- except this doofus-

@nycgps /middlefinger love you, no homo

 

If you are racing then that changes everything. I DD mine so I need that low-end torque, but if you are keeping the revs high then yeah, you could keep it open or open it earlier, etc.

 

how are you wiring it open and closed butterfly's? Like. Mechanic wire. Wrapping it around something. Can you provide pictures or any more updates?

 

For an engine that doesn’t need to operate under 4000 rpm it should be fine, but you wouldn’t want to take it out and use a block plate because the resulting open chamber in the middle of the runners is going to create at lot of turbulence that will do more harm than good imo. Idle would likely be an issue unless you raise it up around 1000 rpm or more and the engine is going to be slow to respond below 3500 rpm. All this is doing is keeping the secondary ports open all the time, which is too much airflow capability at low rpm resulting in low velocity through the runners. It would eliminate a slight response factor, but if you have a proper engine and intake valve system to begin with then this shouldn’t be needed. I can appreciate the simplicity of it for something like an airplane application etc. , not really so much for a car.

And no offence, but if you need to ask how to wire it open then this is likely way beyond anything you should be messing with.

 

Dani, You seem knowledgeable enough to know that the LIM system of valves are designed to enhance responsiveness and performance across the rev range. So, "fixing'' the SSV open doesn't enhance performance capability that it already has... where needed in the upper rpms, . BUT it will degrade performance in lower rpms as h/b explained.



So, can you clarify your application, i.e. why you believe this a good idea? and provide more context...
- Do you mean revving & racing in the streets?
- Or do you mean formally "racing"?
- If formal racing, what type?
- Are you turbo / super-charged?

"Primum non nocere". First, do no harm!

 

And no offence, but if you need to ask how to wire it open then this is likely way beyond anything you should be messing with.[/QUOTE]
No offense taken. Im unfortunately someone that works on cars as well. And basically I was only asking because this isnt a good idea and wanted to know the actual results?. I'm pretty sure I understood how he wired it, but wanted to know more about what happened during and after.

 

 

Mine is wired open (race car) but only to remove a potential point of failure (I have had the solenoid fail). Pretty easy to do. I'll get a pic up if you need one.

 

 

It is my plan to run a Holley manifold with an adapter plate leaving all four intake open. What say you?

 

Are you still running this setup?

 

It's the worst idea ever for this particular engine. See Posts #11 and #13 above.
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We'll see...

 

No ...... you'll see ..... we already know!

 

Really!!? So what you sayin is you are on the mazda developmentent team engineering the impossible and I should just bow down and follow, design the vehicle that I own according to what "WE" say....ok Im pretty sure you are right in your own eyes but let me ask this question ....do "WE" think they said the same thing to Felix Wankel? Not trying to start anything just a little put off when folk throw shade on the ideas of others...

 

Do it mate, be a pioneer, post results

 

You literally asked "what say you?", don't throw a fit when you get answers. There are pretty obvious reasons this is not a good idea, that might save you a bunch of money and work of you cared to read about them above.

 

I'm going to put square shaped tires on my car. I'll have a bigger contact patch which should give me more traction for racing.


That's the kind of argument trying to be made in this thread right now. This is why engineers go to school to you know... engineer things. If improvements were made as easy and with as little R&D as demonstrated in this thread, we would have rotary engines that ran for a 1,000,000 miles and made 5,000 horsepower with thirteen rotors at 143 miles per gallon, all while giving back-to-back happy endings to Felix Wankel from beyond the grave.

Just stop while ahead, please.

 

No, I'm saying you ought to educate yourself first, because clearly you don't either understand this engine and why the suggested intake manifold and fueling mods are bad ideas that aren't going to generate any fruit. Otherwise you wouldn't even be asking us, let alone arguing the point after we provide knowledgeable answers to your question. Don't get me wrong, I understand exactly what you're saying wrt ideas and everyone else does too. Except, you clearly are lacking the understanding about why the engine output will suffer in almost every regard.

It's not that people are just being negative or can't see the genius behind the proposed mods. It really is a very bad idea in every regard that in turn, reflects back directly on you. If you can prove otherwise then come back and rub our noses in it, but am 99.99999999999999999999999999999999999999999999999 9999999999999999999999999999999999999999999% sure that's never going to happen. Only reason I don't list 100% is because with God nothing is impossible, but there's nothing righteous or holy likely to come out of this and you're pretty much doomed to crash & burn trying it.
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So what were the final results? I have read other threads were the SSV being stuck open didn't effect performance or drivability - the main thing was a check engine light.

 

no, if it doesn’t open then the secondary ports are blocked and the engine will starve for intake from around 4000 rpm and higher with a significant power loss.

further, the idea in this thread is terrible and only demonstrates a complete lack of understanding on how this engine operates effectively. The exception as previously mention is for a race car not needing performance below 4000 rpm and then the SSV can be open.
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