RX7 VAF and Protege resonator on a 1.6 SOHC MX3 (PICS)

rukick · Post by **rukick** » March 11th, 2005, 12:43 am

I have been working on making a custom cold air intake for my new 94 protégé LX. I incorporated the protégé resonator and the RX7 VAF and finally got it tuned right. Just for fun I thought I would switch everything over to my 1.6 SOHC MX3 and see how it worked. I was amazed at the difference and how nice it ran. It idled better, no hesitations at lower RPMS, and it felt like it had nice HP gains. The protégé resonator makes it easy to hook up the RX7 VAF because you can take off the little rubber spacer and it fits like a glove. The resonator has a 3 inch opening on the VAF side after you take off the rubber spacer and a 2.5 inch opening on the engine side. As for tuning the VAF, 5 clicks counter clockwise did it just right for my car. I'll get some pics up tomorrow.

rukick · Post by **rukick** » March 11th, 2005, 8:56 am

Here are the pics. I think the resonator and RX7 VAF are great mods for the 1.6 SOHC. They are cheap parts to get and it should make for better throttle response, more low end torque and more HP on the top.

plusinfinit · Post by **plusinfinit** » March 11th, 2005, 10:51 am

what 5 clicks are you talking about?

rukick · Post by **rukick** » March 11th, 2005, 1:23 pm

When you first put the VAF on with no adjustment you get a nasty hesitation between 2 and 3 thousand RPMS and it may even cause the engine to stall. You need to tune the VAF by cutting the silicone around the black cover. Inside is a spring that controls how the VAF opens and closes. There is a big wheel with notches on it that allows you to adjust the tension of that spring. Mark the wheel with a sharpie to show its original position, then move it a click at a time until you get rid of that hesitation completely. Usually that involves 2-6 clicks counter clockwise. I reset my ECU between every click by disconnecting the wire on the negative battery terminal for about 5 minutes. I know there is a more precise way of checking to see if it is right but this works too. It really is not hard at all once you get the black cover off, however I have seen that 1 click can make a difference of + or - 4 hp. I am going to take it to the dyno to make sure I got it right. There are dyno sheets on Protegeclub.com that show 4-5 extra torque and 14 more hp when it is tuned properly.

93SOHC · Post by **93SOHC** » March 11th, 2005, 1:28 pm

wtf is that black box in the middle of all that?

rukick · Post by **rukick** » March 11th, 2005, 1:59 pm

That is the resonator from the Protege LX.

93SOHC · Post by **93SOHC** » March 11th, 2005, 2:03 pm

what does that do? It may sound like a stoooopid ? but i'm doin the BP swap soon, should I get one?

manowar821 · Post by **manowar821** » March 11th, 2005, 2:18 pm

yah, what the heck is a resonator?? And... where can I get it..?

pedro · Post by **pedro** » March 11th, 2005, 2:23 pm

and why would someone put a resonator ... the best air intake systeme that you could get for an N/A is a pipe coming from the Throttle body to the MAF/VAF then to a source of fresh air ... we put filter to be sure to get some clean air...anything else would be useless and/or restrictive ...

maybe im wrong, but I cant see why you would need that exept maybe for the sound ?

rukick · Post by **rukick** » March 11th, 2005, 2:49 pm

It (edit- The resonator) comes on the Protege LX as part of the stock intake. Honestly I don't know how it works, but guys on protegeclub.com say it adds throttle response, and diminishes the loss of low end power when you add more air flow without losing the high end power that comes with more air flow. Do a search over there and you will see dyno results and lots of discussion about it.

I think you can go to the junk yard and grab it off any 90-94 Protégé LX.

pedro · Post by **pedro** » March 11th, 2005, 2:52 pm

rukick wrote:Honestly I don't know how it works, but guys on protegeclub.com say it adds throttle response, and diminishes the loss of low end power when you add more air flow without losing the high end power that comes with more air flow. Do a search over there and you will see dyno results and lots of discussion about it.

I think you can go to the junk yard and grab it off any 90-94 Protégé LX.

yes I can understand for the VAF cause it probably got a bigger diameter that flow more... and maybe its even more precise that the one you had before...but thats the resonnator that I cant understand

rukick · Post by **rukick** » March 11th, 2005, 3:12 pm

pedro wrote:
rukick wrote:Honestly I don't know how it works, but guys on protegeclub.com say it adds throttle response, and diminishes the loss of low end power when you add more air flow without losing the high end power that comes with more air flow. Do a search over there and you will see dyno results and lots of discussion about it.

I think you can go to the junk yard and grab it off any 90-94 Protégé LX.
yes I can understand for the VAF cause it probably got a bigger diameter that flow more... and maybe its even more precise that the one you had before...but thats the resonnator that I cant understand

I was talking about the resonator when I said "it" not the VAF.

This is a quote from protegeclub.com: "any intake kit or cai that would remove your "resonator box" wouldnt really be benefical for the car. the resonator box is the little black box next to the Air Flow Meter. Its used to absorb the air wave that could hit close the air flow meter. it has been proven to help low/mid power range.

so an all the way metal cai would remove the box. so it's up to you in what range of power your looking.

nb: in my own theories, the resonator box would help throttle response."

guyaverage · Post by **guyaverage** » March 11th, 2005, 3:12 pm

If someone dyno'd a before and after with and without the resonator, I may believe it. But every intake mod I have ever seen, the only ones that improved response or power were with the resonator removed. Most intake resonators are for nothing more than noise control (an if you dont already know, intakes produce a LOT of noise, especially at higher throttle openings).

If it IS in there to improve response, I would think it would be in a very narrow rpm range, not across the board. Maybe to harness the natural frequency of the intake against the engine valve timing or something like that (like a VICs system or something similar) at a certain rpm range, but stuff like that is usually in the intake manifold and has some amount of control in it, not in a fixed state in the rubber intake piping.

papa roached · Post by **papa roached** » March 11th, 2005, 3:14 pm

they also used these resonator boxes on the SOHC 323 B6, the resonator uses sounds waves to help charge the cylenders with air, 323 guys have reported a feelable loss in power from removing it

Typhoonk · Post by **Typhoonk** » March 11th, 2005, 3:26 pm

where'd you get the tube that goes from the Throttle body to the Maf? I need one that has the IAC tube connection, and the crank case connection? Where'd you get it!!!???!?!

resonance -> The increase in amplitude of oscillation of an electric or mechanical system exposed to a periodic force whose frequency is equal or very close to the natural undamped frequency of the system

resonator -> A hollow chamber or cavity with dimensions chosen to permit internal resonant oscillation of electromagnetic or acoustical waves of specific frequencies.

Basically it takes the noise the air makes when going in, and cancells some of it out so it is quiet-er. As for performance, the resonance of a frequency in a air intake has too many factors to play with - but that's why you see those intake inserts and stuff with the fan blades in em, so you can get performance out of resonacne science - it's just freak'n complicated!!!