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Hi guys;

Been reading up on the HKS Twin Power units that claim to increase performance by doing things to the spark (ignition modification).

Anyone using one of these at the moment and have some more information on how it works and how effective it is?

Does it require a re-tune?

Thanks

Stan

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Well I don't know what type of power I'm hoping to make...

The price for hte CDI is not cheap; so if I do get it, it better be worth it.

Stezzo = stereo? I'm not too fussed; I've pretty much removed most of my stereo anyway.

Well I don't know what type of power I'm hoping to make...

The price for hte CDI is not cheap; so if I do get it, it better be worth it.

Stezzo = stereo? I'm not too fussed; I've pretty much removed most of my stereo anyway.

yes stezzo = stereo

the twin power does an exceptional job for something so innoccuous, but put it this way- ur engine internals will probably die before your nice new R34 coils run out of spark if you have a .7mm plug gap

Yeah already got the Splitfires and the plugs are at 0.7mm

Dunno; I'm definitely not running out of spark - just looking at this Twin Power thing as I read about it and it sounded worthwhile.

we use the twin spark in conjunction with the splitfire coils, as due to high boost and small plug gap we were fouling plugs getting the car from the pits to the staging lanes....problem is now solved.

never had a missfire since

Thanks Steve; that's the type of response I was hoping to get - someone with a story to tell...

Cheers

S

u just wanted someone to justify ur expensive purchase :)

but yeah- you will be able to run bigger plug gaps at high boost with one

we use the twin spark in conjunction with the splitfire coils, as due to high boost and small plug gap we were fouling plugs getting the car from the pits to the staging lanes....problem is now solved.

never had a missfire since

I also run the same as DiRTgarage - twin spark CDI with splitfires. It certainly gives a strong spark and stopped the infamous "intermittant misfire" that so many PFC owners report. I bought the vehicle specific harness also which makes this a "plug and play" device to install.

Thanks Steve; that's the type of response I was hoping to get - someone with a story to tell...

Cheers

S

There are many many cars that are using them... and thats as far as that story shall go.

Remember i ran some good results, IMO you wont need anything until you get over 350-400rwkw as thats when your running lots of boost and small gaps.

I had spark blow out around the 360 mark, but then that was on 10 year old coils. Not brand new splitfires.

Friend of mine is looking to make them himself, if he ever gets around to it i'll post up about it... but i doubt it'll happen anytime soon as it would take a lot to make any money back on em :)

But i think they are like $600-$700 now anyway, which is pretty cheap and saves stuffing around

Well i use the HKS twin power CDI unit in conjunction with the splitfires, and i run a gap of 1.1mm on nearly 2 bar. its is wothwhile if you run over 400 awkW. I bought the unit because my car was misfiring at 20 psi on splitfires, put it in and the missfire stopped immediatley. and now i dail in 23 psi of solid T04Z boost and it fires at 1.1mm.

sounds like a usefull device if running high power levels, can someone explain the advantege of running a large plug gap like 1.1m and high boost? if you had gapped your plugs down to 0.7mm and was running a lot of boost would this be a disadvantage?

Edited by Drift_Mulisha

The HKS Twin power units I have seen (both DLI’s) are not “true” CDI ie; Capacitive Discharge Ignition. They simply can’t be, using the optional harness, they are only wired into the positive supply to the spark plugs. The negative supply is still controlled by the standard ignitor. A true CDI would need to be wired into both the positive and the negative supply to the coil. I know HKS claim CDI like qualities, but that could simply mean that they use capacitor discharge to move the increased voltage and don’t actually switch the polarity as “true” CDI does.

From what I can tell, the HKS Twin power simply increases the voltage at the primary winding of the coil and this gives a higher arc over voltage output from the secondary windings. This is triggered using the negative connection by the standard ignitor.

The negative circuit is like this ECU  Ignitor  Coil  Plug (the Twin Power is not in this circuit)

The positive circuit is like this Battery  Twin Power  Coil

Unfortunately I haven’t had a car with a HKS Twin Power for long enough to test out the primary winding voltage. But if my guess is right, all it does is increase the voltage from 12-14 volts to perhaps 18-20 volts. This would then result in an increase in voltage at the coil discharge from around 40,000 volts to 60,000 volts. Which is a substantial benefit, if the coils can handle it. Step up DC transformers are around $40 for a 2 amp unit compared to ~$500 for a Twin Power. Hence it would worthwhile if someone with a HKS Twin Power unit could actually measure the input voltage to the coils. Then we would know the target voltage.

For the guys that have HKS Twin power units, are you using them on cars with separate ignitors (ie; R32 and early R33)? Is anyone using one on a late R33 or R34 with the ignitor on the coil style?

To function it really needs to go ECU  Ignitor  Twin Power  Coil  Plug

Since the ignitior is at the coil in those models I can’t understand how the Twin Power fits into that circuit at all.

;) cheers :(

PS; a word of warning for te guys with Twin Power units, try and not get them wet when they are in use. In the US there is a bit of a campaign running by guys that have had 3 or 4 of them fail under those circumstances.

  • 1 year later...
Unfortunately I haven’t had a car with a HKS Twin Power for long enough to test out the primary winding voltage. But if my guess is right, all it does is increase the voltage from 12-14 volts to perhaps 18-20 volts. This would then result in an increase in voltage at the coil discharge from around 40,000 volts to 60,000 volts. Which is a substantial benefit, if the coils can handle it. Step up DC transformers are around $40 for a 2 amp unit compared to ~$500 for a Twin Power. Hence it would worthwhile if someone with a HKS Twin Power unit could actually measure the input voltage to the coils. Then we would know the target voltage.

I saw this post ages ago but never had a twin power to play with well now I do :spank:

I also have not been able to fine a definative explanation anywhere on the net on what it does exactly other then Sydneykids. Just heaps of advertising junk.

I've set up my R32 GTR on the dyno which has a misfire at 6200rpm on 19psi with a 0.8mm gap. At 17psi there is no misfire, so it is boost and therfore cylinder pressure sensitive. I have tried "everything" to get rid of it .... a good test mule !

Setup:

I have removed number 1 coil and placed a normal ignition lead between the coil and the plug no I can measure true secondary firing pattern and examine the burn voltage and burn time.

I have an amps clamp on the ignitor earth monitoring charging amps and dwell time.

I have channel 1 monitoring the primary input voltage on coil number 1.

I have a new set of BPCR5ES plugs gapped at 0.9mm (knowing this will make my misfire worse at 19psi and will load the ignition system to prove or disprove the twin power's effectiveness)

Its all set up and we will commence testing tomorrow > stay tuned for the results :yes:

Mike

Edited by The Alchemist

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