gen2fanatic

i have recently started my LS/VTEC conversion. i have the LS block and i have a 2000 civic si head on the way! the problem is that the head does not come with an ECU. i think i have found that i might be able to use my stock ECU from my 91 teg, and put a chip in it to work with the VTEC.

im not quite sure if it will work. if anyone has any tips that might help me or an actual ECU that would work, that would be great. thanks guys

TheOtherDave™

There is no "chip" that will make a non-VTEC ECU control the VTEC system.

Basically, you have two options.
1) Purchase a secondary controller like an APEX'i V-AFC and use it to control engagement RPM and fuel enrichment.

2) Buy a factory VTEC ECU. IMO, it's safer to use this route...but there's an issue you have to address. All of the B-series VTEC ECUs expect to see feedback from a knock sensor in the block. Your B18A block doesn't have a knock sensor installed. So you can either wire up a knock sensor and ground it to the block, or purchase a modified ECU that doesn't require input from a knock sensor.

TheOtherDave™

Oh...I forgot. HASport sells modified ECUs that will work without a knock sensor.

gen2fanatic

so i can just get the VAFC II and keep the stock ECU and that way i can controll the VTEC???

TheOtherDave™

It's feasible, but I am reluctant to recommend it. h:

A V-AFC will be just as expensive as a HASport-modded ECU, and if you aren't careful, it's easy to screw up either on VTEC engagement or fuel enrichment.

I strongly recommend buying a modded VTEC ECU instead.
IMO, it's the safer option. h:

Question: Are you just slapping the head on a stock LS block or have you upgraded and reinforced the bottom end to handle additional revs?

dubcac

Your ECU can be converted to run VTEC, but just adding a VTEC chip won't do it. You may have a problem with OBD2b sensors since it's a 2000 SI head, but I'm not positive. You could get an OBD0 PW0 or PR3 ECU.

TheOtherDave™

But what about the knock sensor issue?
I was under the impression that a stock ECU won't engage VTEC unless that input requirement is either eliminated or emulated.

dubcac

I don't think the B16 ECU's look for a knock sensor, especially on OBD0. The P72 GSR ECU does though...and the 99-00 B20Z and JDM B20B also has a knock sensor.