Mazda 626 Intake Manifold = ********** Intake Manifold

[flat_black]

VICS is not a dual runner setup. It's a resonance chamber that, when opened up, the airflow resonates at both a different pulse frequency, and increases the overall volume of air in the engine. The set of flaps for VICS is just an entrance to the second chamber. The plenum is divided in half, and has runners to either half, the second portion not having a direct route to the throttle body inlet.

Dual runners are cool, but don't mistake this manifold for a dual runner setup. It simply acts as a larger plenum on the same runners.

 

[Spooled]

VICS is not a dual runner setup. It's a resonance chamber that, when opened up, the airflow resonates at both a different pulse frequency, and increases the overall volume of air in the engine. The set of flaps for VICS is just an entrance to the second chamber. The plenum is divided in half, and has runners to either half, the second portion not having a direct route to the throttle body inlet.

Dual runners are cool, but don't mistake this manifold for a dual runner setup. It simply acts as a larger plenum on the same runners.

Thank you. Maybe they'll listen to you.

 

[D323]

Thank you. Maybe they'll listen to you.

lol, I understand. For simplistic reasons I call it a runner... I will use the correct terminology from now on though.

 

[flat_black]

=) Just tryin' to help!

 

[igdrasil]

Thats right, we need to be clear...i usually call it a secondary runner. Its simply a big chamber closer to the head...as it opens, it will bring a closer plenum. I really dont know if its a resonation chamber, like the FSZE IM has.

 

[Mallard]

sigh....

A single runner will be far larger than either runner on a dual runner manifold right?

Incorrect. They will most likely be the same diameter. The limiting factor there is the size of the intake port on the head and the OEM will design the port and the runner to match up as best they can with manufacturing tolerances with either set-up.

Heres another question I have for you. If dual intake runners are better tuned for a flatter curve, then why do ITB setups make so much power? Essentially they are simply a smooth short single runner.

But you're still breathing through the same size throttle body when you use a manifold. Think about the cross-sectional area of the throttle plates and how much that increases. Not to mention how little restriction there is due to the shoft intake runner. ITB's are only good for high rpm's though, while the advantage of being able to switch between two different runner lengths at a certain rpm is to improve low end power and top end at the same time. Regular street driving with ITB's sucks and at certain rpm's you may experience surging. The only exception to this would be the factory BMW I-6's but they still breather through an air-box and a MAF and not just velocity stacks. Their entrie intake system has been tuned for use of ITB's.

As it's been pointed out, it's apparently not a "dual runner" but a dual volume, which works on the same principles. One runner length or plenum volume is not optimal for every rpm, period. If designed correctly you should have the best of both worlds with a dual ___ manifold. ********** showed gains all through his dyno with the manifold, but the chart didn't start until ~4000 rpms.

 

[thejoker0409]

I need some Tylenol.

 

[flat_black]

ITB's are only good for high rpm's though.

Definitely not true. =) ITB's help at whatever RPM they're tuned for... It can be any range, space providing, but is more often than not tuned very high. Also, if you've ever felt the low to mid range torque to be had from a good ITB setup, you'd wonder why every car didn't have them. Then after going deaf, you'd REALIZE why not every car has them. Hehee.

The best type of ITB's I've seen are the ones that are used with stepper motors with gears and a pinion to control the stack length at variable RPM's, so you're always hitting a primary, secondary, or tertiary pulse wave.

 

[Alejo_NIN]

my head hurts....did you find that tylenol?

 

[igdrasil]

Tylenol will not add any HP gains...(hah)

 

[Boston5761]

will the 626 intake manifold bolt right on the protege FS?

 

[Alejo_NIN]

tell me you didn't ask that quetsion!

read back about 270 posts

 

[Boston5761]

try more like 100 posts....but from what i read it worked but his throttle cable was out of place so it gave him a bouncy idle?

 

[jonlong]

I think that the dual runner manifold is most effective on a N/A car. Since Mazda was using the dual runner manifold on the Protege, Protege5, and MP3, they simply continued to use it on the MSP, since it was still being produced.

A dual runner manifold has it's benefits for a N/A car because you want the longer runner to help build air velocity going into the block, but also want less restriction at higher rpms. On a booster car, such as the MSP, you will have enough air velocity because the turbo is forcing the air in. So you want the least restriction possible.

Exhaust is similar. N/A cars want a certain amount of restriction to provide low end torque. Turbo cars have the turbo to provide restriction, so they benefit from the least restrictive exhaust possible.

Bryan (Azian6er) found a significant increase in low-end hp and a mild increase in the top end. He said that it feels more like a N/A car now because of a more linear power band.

And the bouncy idle is taken care of. It was simply an installation problem with the clip that holds the throttle cable in place.

 

[Boston5761]

so on a N/A application this would be un-beneficial right?

 

[Alejo_NIN]

ok, **** it...warranty is over on my car...so i will try this over the weekend.

gonna pick up a mani at the local junkyard...can someone confirm that it is only the 2000 model mani or could be 98-2001?

 

[tunersteve]

So, if I get this all right, the manifold would continue to benefit more if you were to use a larger throttle body as well, right?

 

[RaiderMS3]

Has there been pics of the 626 mani install and dyno proof yet?

 

[Alejo_NIN]

not that i know of

 

[RaiderMS3]

thought so.

lol.