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The Definitive "VVT swap into 90-97 chassis" Megathread.

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The Definitive "VVT swap into 90-97 chassis" Megathread.

 
Old 09-16-2015, 11:35 AM
  #221  
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I have a questions about coolant hoses and which coolant necks to use.

So I did this swap in 2012 and she was running until the oil drain loosened and trashed the engine. Well 3 years later I am getting her going again. Hard lesson learned about tightening down drain plug.

So anyway my question is
I initial used the 1.6 front coolant/thermostat neck and the 1.6 driverside front coolant neck.


My 1.6 had an old Begi partial reroute that brought the heater core output back to the radiator hose that connects betweeen the thermostat housing and the radiator. So I don't need the heater core return line included in the 01-05 drivers side coolant neck.

But the 1.6 drivers side coolant neck requires a tight squeeze on the radiator hose coming from the bottom of the rad. Could I use the 01-05 driverside coolant neck and block the heater core return. Or should I just keep it the way I did it the first time with 1.6 front coolant necks.

Also any reason to keep 01-05 neck on thermostat neck? the 1.6 one clears my BOV better.

What about the rear neck 01-05 or 1.6 neck?
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Old 09-16-2015, 11:38 AM
  #222  
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I used everything off the VVT on mine... There are ports in the engine, so just removed whatever is fitted there (one sensor and one bung) and fitted those from the original engine. Left the rest unmodded.

If you still feel like replacing those parts, it should make no difference.
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Old 09-16-2015, 02:50 PM
  #223  
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Also I was wondering and maybe it would help other too if it's here.

What firmware/software changes are required in the ECU when you change from the CAS and stock earlier coil/igniter to the VVT Coils with built in igniter?

"all of the other changes necessary will happen in the firmware/software of your ECU. "
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Old 09-16-2015, 03:05 PM
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I'm still using CAS on mine, so no changes there. the CAS is either optical or hall. The optical simulates a hall signal anyway.

As for the VVT COPs, they do have an ignitor built into them. You have to bypass the ignitor ALWAYS, as stated in the first post of this thread. All you have to do afterwards is set the dwell time, as the 1.6 at least uses a 5ms dwell. mine are currently running happily at 4ms dwell time.

By losing the ignitor which generates RPM signal to the gauge cluster, you will lose the rev meter as well. You can modify the MS (if it doesn't already have it) to output the tacho output in the wire that goes to the ignitor, and loop that one too (as per the initial post). But not all MS will support that out-of-the-box.
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Old 09-17-2015, 03:34 PM
  #225  
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To keep 01-05 driversside coolant neck do you just change to a 01-05 lower radiator hose? Will it interfere with the turbo and pipings?
A pic of it installed please.
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Old 09-17-2015, 04:12 PM
  #226  
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Didn't change a thing. The original hose just fits normally on the waterpump neck.

Be sure to clean the surface very well as I had to disassemble it 4 times as it was leaking due to rough surface.
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Old 09-17-2015, 04:20 PM
  #227  
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With my early Begi garret turbo system the 1.6 hose comes out the front of the engine between the ac pulley and pw steering pulley. Which neck did turbo guys use? Any pics?
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Old 10-08-2015, 08:48 PM
  #228  
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Dumb question.

The guide says to use an NB throttle cable. I'm swapping in a 2003 (NB) motor, with a 99 (NB) manifold, but retaining my 94 (NA) throttle body (94 chassis).

While my gut tells me the NA cable that matches my throttle body is the one to use, Sav is obviously much more knowledgeable than my gut.



I ***ume the recommendation for an NB throttle cable only applies if one is using an NB throttle body?
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Old 10-08-2015, 08:51 PM
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It's for all cases I think. The issue with the throttle cable is that it's longer in the NA than in the NB, from the sleeve end to the TB spindle. And this is affected by the bracket that is mounted on the manifold.

To be fair, I just fabbed a new bracket and was done with it. Couldn't be arsed swapping the throttle cable. If and when it goes, I'll swap it.
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Old 10-09-2015, 08:11 PM
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Ghetto temporary bracket can be fabbed. Thanks.
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Old 10-10-2015, 02:16 AM
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Ghetto temporary bracket that breaks < OEM throttle cable installed and used as designed
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Originally Posted by codrus View Post
Basically I've come over to the camp of "If something is a reliability problem on the track, just ask Andrew and do what he says".
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Old 10-10-2015, 06:48 AM
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Maybe I mentioned it wrong, but I don't expect the bracket to go. I was saying, when the cable goes, I'll replace it. Pretty sure the bracket I made is more resistant than the OEM one, as I merely extended the NA OEM bracket to fit the NB manifold position.
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Old 10-11-2015, 09:07 PM
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In my 90 with vvt I used a bracket from flying miata and the na cable. Seems to work fine I guess the cable is a little long but theirs plenty of room for the bigger cable it doesn't bend sharply at all. Looks stock.
Thou the bracket is unpainted but the welds are kind of pretty.

Last edited by 90 Turbo; 10-11-2015 at 09:23 PM.
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Old 10-15-2015, 10:51 AM
  #234  
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Does the NB2 header fit into a NA chassis fine? I will be building a 2.5" for the rest of the exhaust so I am not worried about the flange being off. Long term I am planning on switching to a RB header. Any difference in power between the NA and NB ones?
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Old 10-15-2015, 11:41 AM
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I've never tried, but I would imagine it fits just fine. The NB2 header is substantially better than the NB1/NA8 headers.
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Originally Posted by codrus View Post
Basically I've come over to the camp of "If something is a reliability problem on the track, just ask Andrew and do what he says".
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Old 10-15-2015, 11:43 AM
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So good that you can basically fund an RB header by selling it on eBay (seriously, $275-300+ all day).
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Old 10-15-2015, 01:40 PM
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Originally Posted by Savington View Post
I've never tried, but I would imagine it fits just fine. The NB2 header is substantially better than the NB1/NA8 headers.
The spare VVT motor I am picking up comes with the NB2 header. It is a large reason I am buying the motor. Don't have a car for the motor, but having spares sitting around can't be bad.

Originally Posted by Dunning Kruger Affect View Post
So good that you can basically fund an RB header by selling it on eBay (seriously, $275-300+ all day).
It is silly how much the NB2 headers go for. I am also surprised by how well used RB headers hold their value.
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Old 10-15-2015, 01:41 PM
  #238  
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Wtf? I could barely sell mine at 125.
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Old 10-15-2015, 01:44 PM
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I have an NB2 header gathering dust at home. Couldn't be arsed adapting it with the rest of the swap when the car is eventually going to get a new one.
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Old 10-15-2015, 01:49 PM
  #240  
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I have both, lolwut?

The big market for the NB2 header is CA guys who are stuck with the cast iron BP4W manifolds, but they need to be complete with heatshields and EGR tube. For obvious reasons.

As for the NB RB in a NA chassis, didn't Hustler do this when he went back to N/A on the Green Glory Hole? I feel like he had to dent one of the primaries to get it to not whack the steering shaft, but I may be getting that cornfused with someone/something else.
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