Please help me! mini-me swap help.........97'hx head to a 91'a6 block

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wannabjdm

New Member
a couple of years ago i got the head, intake, tb and ecu from a 97'hx(vtec-e) for free so i went forth to install it in my 90' rex si. over some time i got a cold air intake, full exhaust, cam gear and ecu convertion harness from rywire. it's all together, working and tweeking but it dosen't seem to want to run with the 97' parts. i tried the 90' intake and tb but the same results. i still need to get a 2nd o2 but would that matter that much?
 
The vtec-e is the economical engine found in the hx models. D16y5 is the engine code. To make this work correctly, you will have to use an obd0 distributor, your old exhaust manifold, intake manifold and throttlebody. As for the vtec function to work the solenoid will have to be wired to the ecu. From there, you will need a vtec ecu that is obd0 OR, since its all stock, buy a vafc and wire it up that way.
 
he forgot to mention the header, and I dug him up a 4-wire O2 sensor (might need two?).

he's also using the A6 distributor.

ECU is from a 98 HX with a rywire conversion harness.
 
Ok, so I got a obd0 vtec ecu. The car turns over fine but no firing. I went threw everything and found my injectors are not squirting fuel. Anyone have any ideas?
 
If you are using Si obd-0 dizzy use pr3/pw0 ecu for v-tec
You will need to get a knock sensor and wire it up.
keep the 1 wire o2 sensor but will need a secondary o2 are wire up to make it run good.
Wire up the v-tec.
Thats the cheapest way of doing that conversion.
Best way of doing would be go obd-0/obd-1 conversion
1-4 wire o2 conversion and run v-tec wiring.
Will also require the use of a obd-0/obd-1 jumper harness.'
Going this route will be more expensive.
 
Ok, so I got a obd0 vtec ecu. The car turns over fine but no firing. I went threw everything and found my injectors are not squirting fuel. Anyone have any ideas?

Uh...I really doubt that whatever ECU you're using is going to run the motor correctly. First of all, there were no OBD0 single-cam VTEC engines, so the ECU you have is probably for a dual-cam. That's your first mistake. Second, even if you did have an ECU for a single-cam VTEC, it wouldn't work either because the head you're using has the VTEC-E, which operates differently than the standard single-cam VTEC.

You were on the right track with the conversion harness from Rywire. You need to use the head's original OBD2 ECU to make this work. And yes, you will need to wire up the second O2 sensor or somehow account for it in order to make the car run smoothly...
 
Regardless of the ecu the injectors are not delivering fuel. I had it running and idleing but it quit. I hear clicking under the dash, fuel rail has got plenty of gas, all connections are made but no fuel threw the injectors.
 
I was just reading another post and dude had the same prob. His timming was off but I made sure mines good yesterday. I'm gonna go threw and recheck all my grounds plus I have a nrg ground kit so I'm gonna get crazy with the grounds. Would adding a ground to the resister box be ok?
 
Regardless of the ecu the injectors are not delivering fuel. I had it running and idleing but it quit. I hear clicking under the dash, fuel rail has got plenty of gas, all connections are made but no fuel threw the injectors.

I was just reading another post and dude had the same prob. His timming was off but I made sure mines good yesterday. I'm gonna go threw and recheck all my grounds plus I have a nrg ground kit so I'm gonna get crazy with the grounds. Would adding a ground to the resister box be ok?

Do whatever you want man. You go ahead and "go crazy" on those grounds. It's still going to run shitty until you use the correct ECU or one chipped and loaded with maps for your particular engine setup. Seriously, why would you use an ECU meant for a B16 on a single-cam VTEC-E engine? Does that make any sense at all?

Do people think Honda ECUs are magical and they'll just correctly run any motor you put them on??? Because that's what it seems like...
 
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i dont understand why your wasting all this time and money to put this head on your car anyway, cause in the end it will probably be slower. as mentioned already i believe, that vtec-e head is for gas mileage not performace. this whole thing has fail written all over it
 
i dont understand why your wasting all this time and money to put this head on your car anyway, cause in the end it will probably be slower. as mentioned already i believe, that vtec-e head is for gas mileage not performace. this whole thing has fail written all over it

and why exactly would it be slower? when I had the HX that all the parts came off (with stock compression) it had awesome hops on the freeway and you could feel when the VTEC hit.

yes, the VTEC-e engine/tranny package was designed for high gas milage, most of that was in the transmission that had extremely tall gears it would hold 3rd gear until 110MPH. EX models were 115 HP, HX are rated at 120 + more torque.



also it seems I am going to have to be the one to ask the ultra dumbass question, how does an ECU determine how many cams the engine it is running has????
 
yes, the VTEC-e engine/tranny package was designed for high gas milage, most of that was in the transmission that had extremely tall gears it would hold 3rd gear until 110MPH. EX models were 115 HP, HX are rated at 120 + more torque.

I think you got that backwards. The HX makes 115 horses and 100 ft/lbs torque, and the EX makes 127 horses and 108 ft/lbs torque. The difference is that the HX makes power lower in the power-band (like you said)...
 
to all hatters who didn't believe

well I wanted to let everyone know I got my car running and it runs great. I just had replace a fuse. Oh' yeah the pwo(obd0) ecu works great and the engine and combonation are working well together.
 
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