whrench heads, would the car run this way?
whrench heads, would the car run this way?
ok, now in my head i dont think it will work without throwing codes at the very least.
now would a civic lx with lx ecu, run ok with an ex head installed. now i know vtec wouldnt kick in. but i mean as far as the change in compression. what does everyone think would happen?
now would a civic lx with lx ecu, run ok with an ex head installed. now i know vtec wouldnt kick in. but i mean as far as the change in compression. what does everyone think would happen?
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From: NV
Rep Power: 812 
if all you added was the head, yes it will run, as long as you keep the rpm low under 3k. it wont have much power above that anyway. may want to read the head swap thread again
explain why you say to read it again.
yea vtec should kick in around 4200rpm it seams to me. im ok with it not kicking in. maybe ill put the lx cam in lol ye right jk. anyways......
im worried that its gonna throw codes for the changes in parameters at least as far as ignition timing.
yea vtec should kick in around 4200rpm it seams to me. im ok with it not kicking in. maybe ill put the lx cam in lol ye right jk. anyways......
im worried that its gonna throw codes for the changes in parameters at least as far as ignition timing.
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From: NV
Rep Power: 812 oh there was some new questions asked at the end i cant remember exactly but it talked about running with the old ecu or no tuned vafc to get to a shop and i think it was okay. ya vtec technically wont engage until 4500rpm with full throttle. i doubt you will even notice any difference if you drive the car normally. and the engine light should not come on either because the ecu believes there is no vtec. it obviously wont run at its best, but it will run without issues. ignition timing is automatically set, so when you swap the ecu later, it will readjust itself.
im not swapping any ecu's. my main concern was the ecu being programmed to work on certain parameters. and the higher compression would need the computer to work on different parameters so although i know it will all be fine because the computer will work it out, im worried that a cel will be thrown for this reason but anyways trial and error will most likely be my method.
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From: NV
Rep Power: 812 what are you doing then, just tuning a vafcii? if youre worried about ecu parameters, it is pretty flexible to calculate stuff. im sure it wont mess up. there are plenty of people running lx ecu with a vafc and working fine. i doubt there would be problems.
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Rep Power: 360 Do you even have a Vtec controller or is the solenoid just disconnected? This is an important question.
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Originally Posted by gearbox
oh there was some new questions asked at the end i cant remember exactly but it talked about running with the old ecu or no tuned vafc to get to a shop and i think it was okay. ya vtec technically wont engage until 4500rpm with full throttle. i doubt you will even notice any difference if you drive the car normally. and the engine light should not come on either because the ecu believes there is no vtec. it obviously wont run at its best, but it will run without issues. ignition timing is automatically set, so when you swap the ecu later, it will readjust itself.
I thought vtec kicked on around 2200 or so? Taking the 12 valve economy mode to regular 16 valve vtec mode. I thought vtec was used to engage from the eco mode to regular mode!! Are you sure there is even a high rpm vtec engagement? If there was low rpm and high rpm vtec that sounds like it would be 3 stage vtec not vtec-e.
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From: NV
Rep Power: 812 weve already had this proven with a data logger. the solenoid only opens at 4500rpm when conditions have been met like 100% throttle, coolant at right temp, oil pressure high enough, etc.
as far as just driving with a vtec head, without tuning, i dont think that would be a good idea. its gonna run, but it will feel like youre in limp mode like you only have 50hp.
as far as just driving with a vtec head, without tuning, i dont think that would be a good idea. its gonna run, but it will feel like youre in limp mode like you only have 50hp.
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Originally Posted by ncirom2003
im not tuning anything.
stock lx ecu, with ex head thrown on.
im removing all my stuff and selling it so i wanna figure out if it will be ok to drive around like this.
stock lx ecu, with ex head thrown on.
im removing all my stuff and selling it so i wanna figure out if it will be ok to drive around like this.
Originally Posted by gearbox
weve already had this proven with a data logger. the solenoid only opens at 4500rpm when conditions have been met like 100% throttle, coolant at right temp, oil pressure high enough, etc.
as far as just driving with a vtec head, without tuning, i dont think that would be a good idea. its gonna run, but it will feel like youre in limp mode like you only have 50hp.
as far as just driving with a vtec head, without tuning, i dont think that would be a good idea. its gonna run, but it will feel like youre in limp mode like you only have 50hp.
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From: NV
Rep Power: 812 you wont have all the valves opening, so you will not have an engine that performs at its full potential. like everyone mentioned, drive it slow keeping it around 3k rpms and you wont notice a difference. rev it up and the extra valves wont open, so basically you wont get any extra hp that you would before. youre gonna be revving past 4k and the car wont be getting enough air basically, so it will start to feel like the car is struggling. i know from experience people who "turned off" the vtec with the vafc and noticed a huge power loss. with an EX camshaft, you are forcing it to stay in lo cam profile, and there is no way either electronic or physical to make use of the other cam profile.
Last edited by gearbox; Sep 5, 2006 at 08:45 PM.
yea i know that, i thought you were referring to the whole rpm range when you said it will be like driving in limp mode. the vtec doesnt kick in now just cus the tuner was retarded and didnt do it and now it would mess with the tune...plus i dont give a ****.
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Originally Posted by civydcex
I dont see the point of the swap then!! If running on 12 valves only, throughout the entire rpm range what is the point? It is pointless
Originally Posted by ncirom2003
id like to ask your reasoning and any proof behind this statement.
Last edited by 03-Acura-1.7-EL; Sep 8, 2006 at 02:34 PM. Reason: Automerged Doublepost
Originally Posted by 03-Acura-1.7-EL
I see his point
If you want I can probably think of trading in my EX stock cam for your Turbo one...
If you want I can probably think of trading in my EX stock cam for your Turbo one...
as for the cam, i have stock lx, stock ex, and turbo cam. maybe ill throw the lx cam in lol. (hmm now im actually wondering if it would fit)
Originally Posted by gmcuajo
if not have a vafc or something, use an rpm switch, or something like a shift light for the vtec
Last edited by ncirom2003; Sep 8, 2006 at 06:17 PM. Reason: Automerged Doublepost
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