D15Z1 into 89 crx dx
- Thread starter hoppinrex
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I want to know this as well, but more likely for a SI, if there is any difference
;will do some searches and post info here, but any help would be great, although i know its probably the same old question again.
have a job that requires a LOT of travel.
Update:
From what I am piecing together from various swap articles.
First, for DX owners exclusivly:
"A note to DX owners, all of these swaps will require swapping from your engines DPFI (dual point fuel inj) system to the more common MPFI (multi-point fuel inj)."
From there, the VX engine should physically bolt right in. From there:
"The block does bolt right in physically if you use your si tranny(so dx and hf tranny? what about the D15z1) but there are a few changes to be made in the wiring.
The VTEC needs a way to be activated. Easiest thing to do is wire up a RPM sensitive switch to have it activate the VTEC at a preset RPM, like 4400. While easy, it has some drawbacks. Normally, this engine’s ecu would be used for this and when VTEC comes on, it gives the engine a richer fuel curve and makes sure oil pressure is adequate. So there is your other option, convert to the entire D16Z6 wiring harness and ecu."
My main questions, by doing a RPM hack to activate v-tec, will it retain its fuel efficiency? Is that even how V-TEC-E works? or is it more complex? does the air-fuel ratio need to be adjusted? If it works like that, what RPM should it be activated? What about the oxygen sensor not being there, will the engine work properly without proper OBD-1 wiring conversion.
the Z1 engine will bolt to any 88-91 CRX/Civic transmission, but best to stay away from 88 transmissions due to clutch incompatibilty - the 89-91 CRX HF transmission has the best gearing for fuel economy - the Si transmission would not be a good choice due to its low gearing - the engine will not bolt directly into the 88-91 CRX/Civic chassis without first changing the driver's side mount that is bolted to the block - you need to swap the one from your old engine onto the Z1
in order to maintain the fuel economy of the Z1, you should convert the car to OBD1 so that you can use the P07 ECU from the VX - this would involve purchasing the OBD0 to OBD1 conversion harness and making the other changes required for the conversion - as stated above, if you have a CRX/Civic DX or Civic STD, you would need to do the DPFI to MPFI wiring changes to the engine harness
in order to maintain the fuel economy of the Z1, you should convert the car to OBD1 so that you can use the P07 ECU from the VX - this would involve purchasing the OBD0 to OBD1 conversion harness and making the other changes required for the conversion - as stated above, if you have a CRX/Civic DX or Civic STD, you would need to do the DPFI to MPFI wiring changes to the engine harness