1.7L SOHC Non-Vtec Swap
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Re: 1.7L SOHC Non-Vtec Swap to Vtec
Ok I'm finding out more stuff about this Non-Vtec to Vtec. Do I need to change out any of my wiring inside my car? Like body harness which is inside my glove box. Once again my car which is a Lx now installed a Vtec motor. I have computer for it and harness that plugs into all but do I need to change my wiring from Inside like the Ob2 wiring or anything to help me save time.
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should be possible - the ecu will not know the vtec is there.
Mac, just to correct, the block also have oil squirters to the pistons and slightly higher compression compared to the non-VTEC engine.
not sure of the differences in the camshaft profiles, though...
what will happen is that one of the exhaust valves will most likely not open (almost) since it is what the VTEC will activate, so it will be a 3-valve engine instead of 4-valve. More low end torque but no power in higher end.
Mac, just to correct, the block also have oil squirters to the pistons and slightly higher compression compared to the non-VTEC engine.
not sure of the differences in the camshaft profiles, though...
what will happen is that one of the exhaust valves will most likely not open (almost) since it is what the VTEC will activate, so it will be a 3-valve engine instead of 4-valve. More low end torque but no power in higher end.
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From: Boston
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I too am doing the D17a1 to D17a2 swap. The D17a1 thru a rod bearing. I have a full door SI civic that can no longer be registered. I need some clarification.
I have the a2 installed and running off the a1 computer. The car still has the lx exhaust and computer. The car runs.... just not as good as it should.
I need to finish the a1 to a2 swap.
I will be using the donor SI computer and ignition key. Will this avoid having to flash the computer?
Will be using the SI engine harness to replace the LX harness so it vtec can plugged in.
Will be using the full SI exhaust with its 02 sensors. Front 02 sensor should be ok.
Will the only issue be the 02 sensor in the cat? The SI exhaust has the cat under the car rather than by the manifold in the front of the car. There is no place to plug this in once the engine harness is replaced with the SI harness. This 02 sensor is plugged into a different harness on the SI. How can this issue be addressed?
I have the a2 installed and running off the a1 computer. The car still has the lx exhaust and computer. The car runs.... just not as good as it should.
I need to finish the a1 to a2 swap.
I will be using the donor SI computer and ignition key. Will this avoid having to flash the computer?
Will be using the SI engine harness to replace the LX harness so it vtec can plugged in.
Will be using the full SI exhaust with its 02 sensors. Front 02 sensor should be ok.
Will the only issue be the 02 sensor in the cat? The SI exhaust has the cat under the car rather than by the manifold in the front of the car. There is no place to plug this in once the engine harness is replaced with the SI harness. This 02 sensor is plugged into a different harness on the SI. How can this issue be addressed?
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From: Boston
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should be possible - the ecu will not know the vtec is there.
Mac, just to correct, the block also have oil squirters to the pistons and slightly higher compression compared to the non-VTEC engine.
not sure of the differences in the camshaft profiles, though...
what will happen is that one of the exhaust valves will most likely not open (almost) since it is what the VTEC will activate, so it will be a 3-valve engine instead of 4-valve. More low end torque but no power in higher end.
Mac, just to correct, the block also have oil squirters to the pistons and slightly higher compression compared to the non-VTEC engine.
not sure of the differences in the camshaft profiles, though...
what will happen is that one of the exhaust valves will most likely not open (almost) since it is what the VTEC will activate, so it will be a 3-valve engine instead of 4-valve. More low end torque but no power in higher end.
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Registered!!
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From: Boston
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apexii vafc2 have a VTEC controller.
without an EX ECU or the apexii vafc2, the VTEC is just dead weight
regardless, the VTEC in these cars are VTEC-E
don't be too excited about it
https://www.civicforums.com/forums/3...iscussion.html
without an EX ECU or the apexii vafc2, the VTEC is just dead weight
regardless, the VTEC in these cars are VTEC-E
don't be too excited about it
https://www.civicforums.com/forums/3...iscussion.html
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From: Boston
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apexii vafc2 have a VTEC controller.
without an EX ECU or the apexii vafc2, the VTEC is just dead weight
regardless, the VTEC in these cars are VTEC-E
don't be too excited about it
https://www.civicforums.com/forums/3...iscussion.html
without an EX ECU or the apexii vafc2, the VTEC is just dead weight
regardless, the VTEC in these cars are VTEC-E
don't be too excited about it
https://www.civicforums.com/forums/3...iscussion.html
Joined: Dec 2008
Posts: 15,179
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From: TN
Rep Power: 367 Re: 1.7L SOHC Non-Vtec Swap
the controller is the brains.
Can your body move without a head?
Therefore, the VTEC will just be dead weight.
Also, due to the design of the VTEC-E, the breathing in higher RPM will be hampered.
Can your body move without a head?
Therefore, the VTEC will just be dead weight.
Also, due to the design of the VTEC-E, the breathing in higher RPM will be hampered.
- A non-VTEC will be using all 4 valves all the time, but will not have as much torque in lower RPM and not as much HP in higher RPM compared to having the VTEC working.
- A VTEC engine with non-working VTEC will act normal in lower RPM, but hampered at higher RPM, probably worse than a non-VTEC engine - not tuned for it
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