mpfi swap done, some tips and impressions
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mpfi swap done, some tips and impressions
i finally got my idle worked out. i was running without a pcv valve, once i got that hooked up my idle surge went away.
few things i thought id mention for those who're thinking of doing the swap
- you need a new coolant line to run from the large port on the back of the intake mani to the block (this is mentioned in some write ups) do yourself a favor and pick it up before you start
- grab a new pcv valve beforehand (the stock si one has a 90 degree bend which will make things a bit easier but any parts store pcv will work). i ended up rigging my dx one as a temporary fix but its kinda ghetto
- if you're still running the stock airbox and arm your gonna have some problems. an si intake arm would work.. i didnt have one so i ended up taking a hacksaw to the long pipe coming out of the lid of the airbox just be careful not to cut it down too much or you'll have trouble with the intake arm rubbing on the battery and fusebox
- make sure you torque the manifold down well near the coolant passage on the transmission side of the engine. i didnt at first and i ended up filling my garage with smoke from burning coolant
- and with the coolant lines running to the tb and eacv... dont worry too much about them. i left them off and my car idles perfet and throws no codes (i am planning to hook them up before winter though)
- there is one plug left over when you do the swap. the connector on it, the eacv, and the iat sensor are all the same. mark them beforehand so you dont get them messed up later
other than that the swap went pretty well.
impressions... well it is an improvement but its not that huge of one. i remember reading from one person that it will feel like a whole new car. it wont, at least not to me. i mean it is still just a d15, it still wont push you into your seat like a bigger engine . the main improvements would be that it has more tip in power... before i had to kind of ease into the throttle at low rpms or else the engine would just bog. the mpfi swap improves that a lot. the engine feels like its a lot more willing to rev now and the rpms do climb noticably faster. the higher rev limit on the si ecu is nice too.
overall id say it was worthwhile. with an exhaust i used to hate that id always have to rev out my d15 just to get decent acceleration at a red light or whatever. the mpfi swap definately cured that, now i can ease away at part throttle and still have decent acceleration.
doing the mpfi swap definately helped me learn a lot about my car... to the point where doing a swap doesnt seem like its that much trouble, especially since now most of the wiring is already done. ive got an si cam and a header ready to install when i get the chance, hopefully they'll help me pick up a bit more power.
oh yeah and to those that replied in the post i had about my idle problems and also kenji for the the original dx to zc (in this case si) wiring instructions id like to say thanks.
Modified by tylerspec at 1:12 AM 7/31/2003
few things i thought id mention for those who're thinking of doing the swap
- you need a new coolant line to run from the large port on the back of the intake mani to the block (this is mentioned in some write ups) do yourself a favor and pick it up before you start
- grab a new pcv valve beforehand (the stock si one has a 90 degree bend which will make things a bit easier but any parts store pcv will work). i ended up rigging my dx one as a temporary fix but its kinda ghetto
- if you're still running the stock airbox and arm your gonna have some problems. an si intake arm would work.. i didnt have one so i ended up taking a hacksaw to the long pipe coming out of the lid of the airbox just be careful not to cut it down too much or you'll have trouble with the intake arm rubbing on the battery and fusebox
- make sure you torque the manifold down well near the coolant passage on the transmission side of the engine. i didnt at first and i ended up filling my garage with smoke from burning coolant
- and with the coolant lines running to the tb and eacv... dont worry too much about them. i left them off and my car idles perfet and throws no codes (i am planning to hook them up before winter though)
- there is one plug left over when you do the swap. the connector on it, the eacv, and the iat sensor are all the same. mark them beforehand so you dont get them messed up later
other than that the swap went pretty well.
impressions... well it is an improvement but its not that huge of one. i remember reading from one person that it will feel like a whole new car. it wont, at least not to me. i mean it is still just a d15, it still wont push you into your seat like a bigger engine . the main improvements would be that it has more tip in power... before i had to kind of ease into the throttle at low rpms or else the engine would just bog. the mpfi swap improves that a lot. the engine feels like its a lot more willing to rev now and the rpms do climb noticably faster. the higher rev limit on the si ecu is nice too.
overall id say it was worthwhile. with an exhaust i used to hate that id always have to rev out my d15 just to get decent acceleration at a red light or whatever. the mpfi swap definately cured that, now i can ease away at part throttle and still have decent acceleration.
doing the mpfi swap definately helped me learn a lot about my car... to the point where doing a swap doesnt seem like its that much trouble, especially since now most of the wiring is already done. ive got an si cam and a header ready to install when i get the chance, hopefully they'll help me pick up a bit more power.
oh yeah and to those that replied in the post i had about my idle problems and also kenji for the the original dx to zc (in this case si) wiring instructions id like to say thanks.
Modified by tylerspec at 1:12 AM 7/31/2003
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