The Definitive "VVT swap into 90-97 chassis" Megathread.
#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?
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?
#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. "
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. "
#224
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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.
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.
#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?
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?
#229
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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.
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.
#233
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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.
Thou the bracket is unpainted but the welds are kind of pretty.
Last edited by 90 Turbo; 10-11-2015 at 09:23 PM.
#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?
#237
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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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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.
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.