VTCS/VICS Delete and Intake Manifold Modification

JDM Sam

Banned
For those who don't want to bother with a 626 manifold can do something like this. This is what I do with them.
http://www.mazdaspeedtuning.com/manifold.jpg
http://www.mazdaspeedtuning.com/manifold2.jpg

This creates more air flow, leaner afrs, more midrange to peak power pull. I'll have a dyno graph shortly once i retune the guys car. For a stock untuned car, the afr will still be rich just not as pig rich as it was. A tune will extract more power.

Pros - everything fits properly, you retain vacuum ports, no CEL, sleeper modification, frees up a vacuum port for running an independent source to the bov and wga.

Cons - sleeper modification, labor to hog it all out takes a while

No cold start up issues. You must leave the 2 VTCS/VICS solenoids plugged in, but remove the actuators and all the vacuum lines to the solenoids. You must also remove the green/white check valve in middle of the manifold and put a straight piece of vacuum line there, be sure you use high grade silicone line and reuse the clamps, replace all the gaskets for a leak free seal and torque to specs.

You are increasing the volume of the manifold by hogging out the entire VICS chamber. Deleting the VICS flaps alone doesn't do anything b/c it is just an empty chamber with no air flowing into it. It's just a stagnant air chamber. Instead of a chamber of air opening at 5200 RPM, hogging out the manifold you have a large volume of air all the time.

The VTCS is a emissions system to increase turbulence to improve start up emissions. Other cars have similar systems. VTCS is more of a restriction compared to the VICS.

There was a Miata in Dsport that had a similar modification done on the BP 1.8 and it gained around 25-30 hp from doing this modification, the builder dyno verified it. Car made about 500 hp to the wheels. I spoke to the builder of that Miata and he says its a worthwhile modification alternative to a sheet metal manifold. We were going to offer the service for modification, but it was too labor intensive even on a lathe to offer it to the public. The cast aluminum is difficult to grind down. The amount of the labor would have been around $500 to complete the modification.

It'll work on NA cars, but I have only put it on turbo proteges. The gains from doing this will be more beneficial to turbo cars. I would get a spare manifold somewhere and try this so you can compare the 2 if you are trying do this on an NA protege.
 
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starscream2k1

Boost Junky
:
2007 CWP Mazdaspeed3
Will this work with a unichip and tuning? Right now i have a 626 intake mani and gonna rip the fucker off and go back to the stock mani, but deciding to actually do this mod. Wouldnt it make it the same as the 626 mani in essence? Or am i missing something here?
 

dmention7

beware of perverts...
:
'03.5 Blue MSP #2543
Any chance you have a "before" picture for illustrative purposes? I get what you are saying you did, but I don't have a good picture in my head of specifically what material was removed from the manifold.

If not, I can probably massage the search button into finding one for me. :)
 
:
mazdaspeed protege
these two manifolds are different whitch 1 is the msp mani and wats the other 1 a 626 mani???boreing out the runners wuddnt that create to much turbolance inside the mani???wuddnt u loose power because of that??
 

JDM Sam

Banned
Will this work with a unichip and tuning? Right now i have a 626 intake mani and gonna rip the fucker off and go back to the stock mani, but deciding to actually do this mod. Wouldnt it make it the same as the 626 mani in essence? Or am i missing something here?
Yes.
Yes and no, the 626 manifold is a single long runner manifold, it is where it has no VTCS,VICS, but the manifold volume will be different, and you will retain the factory fuel rail, egr tube, and vacuum ports.
 

ogsp5

225 whp @ 8psi
:
2002 p5 (MSP Powered)
This was done on my manifold for over 1 1/2 years. Nice quick response. And very great response at highway speeds.
 
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:
mazdaspeed protege
^^bump^^^^

these two manifolds are different whitch 1 is the msp mani and wats the other 1 a 626 mani???boreing out the runners wuddnt that create to much turbolance inside the mani???wuddnt u loose power because of that??
 
:
'12 Velocity Red MS3
Any idea as to how long this would actually take? Is this an all day thing? Or am I looking at several days of down time? I think mine is beginning to get stuck more and more, so I'd like to do this.
 

nvmsp

mpnick turbo'd
Good cuz this is what I want to do to mine , I don't want a 626 mani, I hear too many issues with some of them.

How much to do one shipped to you? and, how much to do one that you already have or can get, and ship to me? So I have no down time, cuz I can't afford any downtime really.
 

o0n8

Still have noob questions
:
74 Schwinn Varsity, 75 Camaro (Project), 04 6 Wagon
I would love to try this but can't have a none working car that long. Is the MSP mani different from a reg protege mani on a N/A 2.0? Might find one at a junk yard and give it a try if that's the case.
 

JDM Sam

Banned
if you're doing this mod, then it doesnt matter, ANY 2.0 Protege manifold will work for this mod if you're deleting the entire vtcs/vics rods and valve assembly.
 
:
MSP #408
ok. i have a 626 in right now, and my stocker sitting in the garage. so downtime is not an issue. what is, however, is my lack of mechanical skillz. is there anyway you can post a "how to" with some more step by step pics. i've read this post and studied those 2 pics over and over again, but still don't feel like i'm ready to start cutting away at things. or just pm me a price to send my stocker to you so i can get an idea of my options. thanks.
 
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