ls vtec swap puzzle pls help!

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ok so my buddy got a 91 crx shell and then an ls vtec b16a top b18b1 bottom we put the motor in then it came to wiring... the ecu plugs are butt connected on and this car was dpfi and i had to re do it cuz it wasnt working right and i finally got all the CEL's squared away do to wiring problems and i went to go hit vtec... cant even tell cross over point at all... car is hella slow.. i tried re doing the timing over and over and over again but it never get any closer no matter what its about and inch away from red mark on pully when doing ingnition timing i treid lining everything up over and over but timing always is off the dizzy has to be moved back all the way twards the firewall to be even close i have the jumper plug jumped still makes no differance (blue plug by heater motor) i treid moving the over all timing off so it will even out when i do ingnition timing NOPE that didnt work either... the car stutters and bogs pretty sure do to timing... what am i doing wrong any tips or tricks? please give me your opinion i stuck right now... thank you
 
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im gunna be working on her today too im gunna try and advance the crank timing and leave the cams timing the same and see if will even its self out:mellow:
 
ok finally got the timing right... runs alot better still no vtec or CEL's i put a new soilenoid and presure switch on and checked the ecu connections and ran through all the wiring still no vtec the only conclusion i can come to is not enough oil getting to the soilenoid through the steal braided line.. it comes from the oil presure switch hole to behind the dizzy and that should work i dont get it!!
 
hook your vtech solenoid onto a power supply and see if it work....have someone sit in the car and rev the engine up to 3000 then put the power on the solenoid and see if it kicks in.
 
no i had a friend who's vtec wouldn't work when he put gsr pistons in it started working
 
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im guessing that while your friend (or the shop that did the work) was tearing the motor down and reassambling it may have stumbled across other problems and corrected them as well. there are soo many things that will make vtec not engage, but pistons is not one of them.
 
I made some vtec pistons with my die grinder;) Most people dont know this but the valve reliefs in a ls/b20 arent big enuff to totaly clear the larger valves on a vtec head. You need to make them slightly bigger. If you dont do this you risk bending a valve or even worse breaking the head off from repeated contact with the piston. As to the problem that was posted about test the vtec sol run +12v to it and it should engage. Also what ecu are you running this could help.
 
I made some vtec pistons with my die grinder;) Most people dont know this but the valve reliefs in a ls/b20 arent big enuff to totaly clear the larger valves on a vtec head. You need to make them slightly bigger. If you dont do this you risk bending a valve or even worse breaking the head off from repeated contact with the piston. As to the problem that was posted about test the vtec sol run +12v to it and it should engage. Also what ecu are you running this could help.

Thats not true either. I have seen many ls or b20/vtecs running factory pistons with zero problems. If someone you know is bending valves they probably do not know what they are doing and have the cams out of time.
 
Thats not true either. I have seen many ls or b20/vtecs running factory pistons with zero problems. If someone you know is bending valves they probably do not know what they are doing and have the cams out of time.

your wrong it usualy wont hurt nothing but it will mark the pistons some are just unlucky have other issues
 
damn damn damn.. i posted to get other experianced advice and ppl who have came across this before i didnt built this ls vtec i pretty much have no clue what corners the guy cut while buliding it besides aparent extarnal stuff i have fixed now im just stuck i bulit many honda engine this is not my build of set up all i did is swap it wire it and get it running without codes and the owner doest want me to take off the head and disassemble it...so im lookin for other ideas so stop trying to feed me crap that makes no sense at all pistons dont matter k.. and what ever else you guys said...any GOOD advice? oh ya by the way if you cant spell vtec dont try and tell me stupid shit...thank you
 
ok like i was saying before i use re wired what i could find on the Dpfi harness but while searching through the wires i found the crank pos. sensors and cyl. pos. sensor were switch around on the ecu plugs hope this is it!!
 
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