Converting to Wasted Spark

[Guest lan_killa]

Hi guys

I want to do the wasted spark conversion to my V1 WRX. Can someone please outline the bits I will need and how to install it all

Im really suprised that there isnt a write up in the Tech DIY section on this

[kamineko]

its simple enough to wire up however i believe the dwell timing is different for these types of coil setup. i have tried various setups and a v1/v2 ecu + wasted spark works but poorly. same with a v3/v4 ecu and coil-over-plug.

best mix and match results i had where with igniter-on-coil-over-plugs found on V7 / newer GTB engines. they worked fine on a V2 ecu. here is a link describing the 'mod' http://forums.nasioc.com/forums/showthread.php?t=1192028

this is my experience - some have swapped and say it works fine but i highly doubt it.

[dubbedup]

got all the parts on my wrecked BC5 and can do you a mean price, PM me for details

[Ryan]

Hit ReubenH up, he's done it.

[smokn4]

 dubbedup said:

got all the parts on my wrecked BC5 and can do you a mean price, PM me for details

im also interested in this mod , if the bro dont take you up on your offer do you wanna pm me some details of what you have and a price,

chur

[Guest boostin]

 kamineko said:

its simple enough to wire up however i believe the dwell timing is different for these types of coil setup. i have tried various setups and a v1/v2 ecu + wasted spark works but poorly. same with a v3/v4 ecu and coil-over-plug.

best mix and match results i had where with igniter-on-coil-over-plugs found on V7 / newer GTB engines. they worked fine on a V2 ecu. here is a link describing the 'mod' http://forums.nasioc.com/forums/showthread.php?t=1192028

this is my experience - some have swapped and say it works fine but i highly doubt it.

Agreed. If anything I would convert to the later GTB style coils.

[ReubenH]

Do you want to do wasted spark, or coil pack conversion.

cause wasted sparks easy, just join cyls 1 and 2, and cyls 3 and 4, at the ecu, and done.

Coil pack conversion is also easy, i guess we could do a write up some day. it's pretty straight forward.

I also have some mint condition ignitor-on-coil-on-plug things off me GTB, with loom plugs. If you want to try and fit those. Do they fit EJ20G heads though? hmmm.

[kamineko]

sorry maybe hard to work out from my post but the igniter over coil over plug setup fits Ej20G just fine. read the link, and my post.. again.. lol

[Guest lan_killa]

i want to end up using actuall HT ignition leads, as my current coils = gone burger again

so I want this style of ign setup

[kamineko]

yep

and it can be wired up simply..but

because that coilpack is firing 2 sparkplugs at once, the dwell, or 'charge time' for each fire is longer than needed for single coil-over-plugs

your current ecu (expecting single coil-over-plug) is going to deliver too short a dwell time to run the wasted spark coilpack properly.

it'd run but i expect the problem means a weak spark at high rpm/boost.

[Guest lan_killa]

I might give it a wirl... see what happens... as I cant be fucked having to replace these coils again

any one got a list of what I need???

I assume just leads and the coilpack???

[kamineko]

yup. you can reuse your current igniter. the coilpack requires 12V and the correct pair of wires from the igniter.

[Guest lan_killa]

sweet... will get that sorted asap

[Old Skool Subbie]

What is wasted spark and what is the advantage of using Wasted Spark over just replacing the old coils with new ones?

[kamineko]

coil-over-plug ~ 4 separate coils are fired in sequence one at a time.

wasted spark employs 2 coils (together in one 'coilpack') that fire a pair of plugs at a time. only one cylinder will have just compressed the air/fuel so that one makes use of the spark, the other spark is 'wasted'

usually people get sick of replacing single coil-over-plugs which have died from heat etc and the wasted spark setup is attractive because the coilpack is mounted away from any real heat.

i only got wasted spark to run properly (ie good results on boost) with an ecu tuned for that setup (dwell timing as mentioned). but curious to see how lan_killa gets on

[Guest]

I have built up a harness to convert legacy and wrx coil on plug setups to wasted spark with a single coil and ht leads, the wasted spark setup with ht leads is far more reliable than the crappy old coils from v1 to v2 wrx's and legacies, also its much easier to replace plugs with ht leads and ht leads fail less than coil packs. I may setup a deal including coils, ht leads with the wiring if ppl are interested.

[smokn4]

 EVILRS said:

I have built up a harness to convert legacy and wrx coil on plug setups to wasted spark with a single coil and ht leads, the wasted spark setup with ht leads is far more reliable than the crappy old coils from v1 to v2 wrx's and legacies, also its much easier to replace plugs with ht leads and ht leads fail less than coil packs. I may setup a deal including coils, ht leads with the wiring if ppl are interested.

i could be keen on this

[Guest lan_killa]

how much you after for the harness??? could be interested

[Guest SPANKU]

 ReubenH said:

Do you want to do wasted spark, or coil pack conversion.

cause wasted sparks easy, just join cyls 1 and 2, and cyls 3 and 4, at the ecu, and done.

Coil pack conversion is also easy, i guess we could do a write up some day. it's pretty straight forward.

I also have some mint condition ignitor-on-coil-on-plug things off me GTB, with loom plugs. If you want to try and fit those. Do they fit EJ20G heads though? hmmm.

we try doing the 1+2 3+4 ones already it didnt work

[smokn4]

 SPANKU']

[quote name='ReubenH said:

Do you want to do wasted spark, or coil pack conversion.

cause wasted sparks easy, just join cyls 1 and 2, and cyls 3 and 4, at the ecu, and done.

Coil pack conversion is also easy, i guess we could do a write up some day. it's pretty straight forward.

I also have some mint condition ignitor-on-coil-on-plug things off me GTB, with loom plugs. If you want to try and fit those. Do they fit EJ20G heads though? hmmm.

/quote]

we try doing the 1+2 3+4 ones already it didnt work

did use not end up solving that prob

[Guest SPANKU]

no it concluded that its more work then we though. think we have to get the ignitor to spark at the same time as the plugs

we made some harness for it and done alot of reserch on it.

easiest solution is getting a ver3/4+ loom

[Guest]

I have already done this on a facelift bc5 legacy so I know it works. I would probably sell the harnesses for $80 and the more people interested the cheaper I can do them. Im a mechanic myself so I understand whats needs to be done to get it to work and im happy to help out if ppl are having any trouble. I can also supply wasted spark coils and leads if required.

[ReubenH]

 lan_killa said:

i want to end up using actuall HT ignition leads, as my current coils = gone burger again

so I want this style of ign setup

I miss that car But i immortalised it on wikipedia. Win

[ReubenH]

 SPANKU said:

no it concluded that its more work then we though. think we have to get the ignitor to spark at the same time as the plugs

we made some harness for it and done alot of reserch on it.

easiest solution is getting a ver3/4+ loom

That's odd. Cause joining the ignition wires out of the ECU is what i did when i single converted the legacy. Though i suppose that was a V3 ecu, just sending ignition signals to my ignitors-on-coils-on-plugs.

As for wiring a coil pack setup on a V1/2 WRX. The coil pack has 3 wires going into it, ignition 1, ignition 2, and a third which i don't know if it is power or ground. I know the coilpack grounds through the bolt holes, but i still dunno if it's power or ground. Either way, just find the wires coming from the ignitor to the engine loom with a multi meter. join 1 and 2 and send it into one of the coil pack wires, and join 3 and 4 and send it to the other. figure our if the 3rd wire (middle wire on the coil pack plug) is, and give that a shot. If you fire on the intake and compression strokes, then you have the coils the wrong way round

If you want to convert to the 5-pin ignitor, do the cyl joining on the ecu side.

Here's a diagram that should give you a rough idea of what's going on. The unknown wires the going into the ignitors may or may not actually be grounds. I have yet to figure that out. [edit] Just had a look at my plugs, the middle wire on the ignitor is black. The middle wire on the coilpack is red. Does someone want to clarify that the ignitor's extra wire is ground or 12v? And ditto on the coil pack.

[kamineko]

the igniter is grounded and the coilpack requires +12v

[edit, just checked. the igniter switches ground to the coil inputs.]