How-To: VTCS Removal and Porting

Lewis7789

Evan aka "Lady Hands"
Contributor
:
1995 MX-5, 2006 MZ5, 2001 Yamaha R1
http://www.mazdas247.com/forum/showthread.php?82884-How-To-VTCS-Removal-and-Porting/page9
Post #129. Open the PDF and all the info you'll need is in there.

The bar slides out, it's just a little sticky. Try wiggling while twisting with a pair of channel locks. Which holes do you mean? The one for the solenoid or the holes from the butterfly rod? I filled the rod holes with QuickSteel. I took my IM off about 3 months later to install my rear motor mount and noticed 3/4 of the QuickSteel plugs were gone. So skip that step. I removed the rest of the plugs and ran my motor like that for about a year without any issues.
 

Lewis7789

Evan aka "Lady Hands"
Contributor
:
1995 MX-5, 2006 MZ5, 2001 Yamaha R1
Check to make sure the intake mani is bolted down nice and tight, same with your throttle body. And check for vacuum leaks.
 

Installshield 2

Gothenburg Superiority
I know this is old, but i still see some guys interested in doing this in other threads and are directed to this...and i'll be doing it this winter as well...

just wanted to clarify a few issues though, that seemed to have slipped by over the years:

If you live in areas of the globe with 'real' winters...it is ill-advised to do this modification WITHOUT an MP3 ecu. Contrary to whats been posted a few times in this thread; the Protege 5/ES ecu does NOT run in closed loop mode for cold starts (in fact, these ecu's use closed loop so little its barely ever worth mentioning)...the eec-v p5 flash version has a pre-set table for cold starts depending on initial input from the IAT during cranking...these maps are designed to work with the VTCS system, and with its removal, there are not richer maps to compensate. Cold starting in 10 degree weather requires a ton of fuel without the VTCS system...think of the VTCS as a choke for the stock ecu, only the ecu has no 'primer' to add more fuel, and it doesn't have a map to run with vtcs being removed from the system.

the MP3 ecu isn't programmed to use the VTCS system...its cold start maps incorporate a very rich mixture the old fashioned way; without any mechanical limitations on air flow...

where you live will make the biggest difference. Many claim 40*F and above is acceptable for the p5 ecu without VTCS...but the more you dip below that, the more undriveable your car will be when cold...probably to the point of it not starting at all. I've seen some guys just mashing the throttle to keep it running after cold cranking...and if you're unaware of why thats not a good thing...car tuning might not be the best hobby for you haha.

warmer climates...you'd never know the vtcs was gone.
 
http://www.mazdas247.com/forum/showthread.php?82884-How-To-VTCS-Removal-and-Porting/page9
Post #129. Open the PDF and all the info you'll need is in there.

The bar slides out, it's just a little sticky. Try wiggling while twisting with a pair of channel locks. Which holes do you mean? The one for the solenoid or the holes from the butterfly rod? I filled the rod holes with QuickSteel. I took my IM off about 3 months later to install my rear motor mount and noticed 3/4 of the QuickSteel plugs were gone. So skip that step. I removed the rest of the plugs and ran my motor like that for about a year without any issues.
This is interesting...I was wondering how well QuickSteel would adhere to the manifold. Also there is already an open passage between cylinder '3 and 4' and '1 and 2' for the PCV. Maybe I will just leave those VTCS rod holes open then...and just plug the one to the outside with a bolt.

I took things apart now....Now I am waiting for tomorrow after work to get a taping tool to drill a hole for the bolt. Probably gonna skip porting and stuffs...Not sure if that would really do much.

So 4 out of 8 of my VICS screws came loose. Last time after it made the coins in the dryer sound I kept on getting cylinder 4 misfire. I swapped ignition coils and changed the spark plug and it's still cylinder 4....Maybe the valve is bent...It sucks...
 
:
03 Mazda Protege5 Red,5spd
i am attempting to remove my vtcs butterflies and i would like to use this link but it is broken. does anyone have the write up or a fixed link to the porting and/or removal guide? much appreciated
 
:
03 Silver Protege5
Does anyone have a current write up for vics removal? That pdf is great for the vcts and porting everything out, but I can't even find pictures of the vics removal process
 

dragosurf88

Contributor
:
2002 Mazda Protege5
Does anyone have a current write up for vics removal? That pdf is great for the vcts and porting everything out, but I can't even find pictures of the vics removal process
I wouldn't recommend removing the ViCS, it's a good thing...VICS opens up a secondary short ram ports on the intake after about 5000 rpms...think VTEC (ala Honda)...hence more power at higher RPMs... Removal of VICS would kill your high power.
 

Jackie chan

Team Pro5
:
Pro5
It'll actually kill youre low end torque. High end would actally probably be improved because of the smoother flow and added volume.

And vics removal is basically the same as vtcs removal. you just have to split the manifold.
 
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03 Silver Protege5
If I understand correctly, the vics does not create an additional path for air to flow. It's a chamber with the opening facing the head sealed by a butterfly, and when the engine reaches a certain speed, I believe 5150 or 5200, the butterflies open and the chamber resonates, creating a slight pressure effect and increasing air flow velocity.

However that doesn't mean more air volume, just velocity at the head. For an NA car, the long runner setup is good because it builds torque more effectively below 4,000 rpm. But with a turbo, you don't need that high velocity vacuum because you can create a pressurized chamber via boost.

But if you machine out the sides of the vics chamber and delete the butterflies, you have modified the intake from a low volume, long runner, high velocity intake into a short runner, high volume, low velocity intake.

I'm sure I can figure it out, I've searched the forum can't find any pictures of the machining in progress or the final product before reassembly. Just want to be sure I'm doing it right
 
:
Mazda protege5
Old thread but full of awesome info. I just spent the past 3 days reading over this, can't wait to finish mine up and install.
 
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