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i have one on my car also.

didnt really notice much of a difference but i havent tested it properly and still use standard coils

my plugs are gapped at .6 and ran up to 24psi with standard coils (no twin power).

tried running a .8 gap with the twin power but only up to 20-21psi but would missfire at high rpm.

might get a set of splitfires one day and try a 1.0 gap with 24psi

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WELL, heres the preliminary results......

Charging voltage stayed exactly the same starting at 13.7 volts dropping out to 13.4 volts once the coil had charged, so the red wire into the HKS unit and the coils is just a power wire to run the module I guess

Charging amps rose slightly from 5.9/6 amps to 6.4 amps however dwell time remained unchanged as I expected.

The secondary burn voltage stayed the same at about 0.6kv and burn time remained a bit short at 0.5ms but basicaaly remained unchanged.

These tests were done at 17psi then we ran out of time, BUT will be doing high boost dyno runs tomorrow so will see what happens then and report to this thread. At this stage it seems the Twin power unit increases charging current slightly which MAY help misfires at higher boost settings but certainly makes little or no difference to your car if your engine is running OK and not misfiring to start with.

Mike

WELL, heres the preliminary results......

Charging voltage stayed exactly the same starting at 13.7 volts dropping out to 13.4 volts once the coil had charged, so the red wire into the HKS unit and the coils is just a power wire to run the module I guess

Charging amps rose slightly from 5.9/6 amps to 6.4 amps however dwell time remained unchanged as I expected.

The secondary burn voltage stayed the same at about 0.6kv and burn time remained a bit short at 0.5ms but basicaaly remained unchanged.

These tests were done at 17psi then we ran out of time, BUT will be doing high boost dyno runs tomorrow so will see what happens then and report to this thread. At this stage it seems the Twin power unit increases charging current slightly which MAY help misfires at higher boost settings but certainly makes little or no difference to your car if your engine is running OK and not misfiring to start with.

Mike

Good info so far.

I've only ever really seen the HKS box on cars making over 400rwkw as a base, so running a fair bit of power/boost/airflow.

I can tell you on my car I had all sorts of boost cut issues once I got over 19psi and to fix it I was having to gap my plugs down to as low as 0.4.

Since installing the DLI however I've never had an issue once and the plugs are gapped at the standard 0.8.

I don't know how it works - but it works for me. :/

I can tell you on my car I had all sorts of boost cut issues once I got over 19psi and to fix it I was having to gap my plugs down to as low as 0.4.

Since installing the DLI however I've never had an issue once and the plugs are gapped at the standard 0.8.

I don't know how it works - but it works for me. :bunny:

same here...had splitfires and plugs gapped down to 0.5 and was missfiring. Car would foul plugs getting from the pit to the startline at the track. Having to clear them during the burnout (sometimes affecting the quality of the burnout). Installed HKS igniter and plugs are back up to 0.8mm and never had a fouling or missfire issue since.

I can tell you on my car I had all sorts of boost cut issues once I got over 19psi and to fix it I was having to gap my plugs down to as low as 0.4.

Since installing the DLI however I've never had an issue once and the plugs are gapped at the standard 0.8.

I don't know how it works - but it works for me. :D

Dont bother trying to measure what it does ...They just flat out work a treat!!

Had plenty of Big horsepower cars with splitfires, CDI etc that miss when the boost is wound up...add a DLI and problem gone forever :)

Anyone who says it doesn't work isn't making enough power to notice the difference or has some other problem.

Never tried to work out what it does, don't really care to know...

Maybe just some HKS magic in that gold box...

cheers

Dont bother trying to measure what it does ...They just flat out work a treat!!

Had plenty of Big horsepower cars with splitfires, CDI etc that miss when the boost is wound up...add a DLI and problem gone forever :)

Anyone who says it doesn't work isn't making enough power to notice the difference or has some other problem.

Never tried to work out what it does, don't really care to know...

Maybe just some HKS magic in that gold box...

cheers

There is no magic in car electronics, it's either volts and/or amps.

Cheers

Gary

  • 2 years later...
WELL, heres the preliminary results......

Charging voltage stayed exactly the same starting at 13.7 volts dropping out to 13.4 volts once the coil had charged, so the red wire into the HKS unit and the coils is just a power wire to run the module I guess

Charging amps rose slightly from 5.9/6 amps to 6.4 amps however dwell time remained unchanged as I expected.

The secondary burn voltage stayed the same at about 0.6kv and burn time remained a bit short at 0.5ms but basicaaly remained unchanged.

These tests were done at 17psi then we ran out of time, BUT will be doing high boost dyno runs tomorrow so will see what happens then and report to this thread. At this stage it seems the Twin power unit increases charging current slightly which MAY help misfires at higher boost settings but certainly makes little or no difference to your car if your engine is running OK and not misfiring to start with.

Mike

Can you please continue The Alchemist!!?? Really interested as looking at one of these units to finish off my combo as I'm starting to blow the spark out as I'm starting to push 430rwkw at 25psi on an rb25. Please finish!

Can you please continue The Alchemist!!?? Really interested as looking at one of these units to finish off my combo as I'm starting to blow the spark out as I'm starting to push 430rwkw at 25psi on an rb25. Please finish!

I have another post on this forum about what happened ab0out a month ago...the HKS unit randomly shit itself while I was driving at 50km/hr stalling the engine. I found the problem quite quickly as the smoke was let out!!!

Unpluged the harness and plugged in the factory loom and I was away again.

Base at work we pulled the unit to bits to have a look at what makes it tick.

Basically it has a row of 6 transitors/caps/ resistors on a board that triggers off each ignitor trigger for each coil. This is connected to a large single 400V cap that is charging of the power wire to the unit, a magnetic coil unit similar to a ignition coil which either absorbs the current dump when each ignition coil fires or stores up energy to be realeased thru the 400V cap when it fires. Finally theres a couple of timer chips and power transitors and a little power supply board in there to run the thing. Its very well made and well designed to jam everything in such a small unit.

The compenent that failed was a small surface mount resistor on one of the 6 trigger circuits. Unfortunately its full of resin which had to be carefully dug out to see what the problem was. Impossible to fix!

Basically I found that the engine at 360rwkw made the same power with or without the unit plugged in. Tested in house on our own dyno. Believe me I WANTED to see a difference!

What we did in the end to eliminate the miss was to lean the mixture out from 11.9/12 to 12.2:1. There was simply to much fuel/air for the ignition system to ignite properly > the HKS unit cannot fix this problem. I'm sure that at some stage you will need some sort of ignition amplifier but at what that point is exactly I'm unsure as I have not reached it yet.

The most important thing you can do though is to insure you have an excellant power supply to your coils and I don't mean pull out a voltmeter and and proble it to check for 12V either. You need a good scope to probe the power supply during coil firing. If you see more than a 0.5V drop when the coil fires you have a big problem. My Car had 2V drop !!!!!!!!! Old wiring/relays etc ass up to resistance that costs in voltage. I wired up a new relay in the fuse box to run my coil power feed directly and I now have a 0.2V drop when the coil fires. Makes a huge difference.

Hope this helps...

Mike

Edited by The Alchemist
  • 3 months later...
The most important thing you can do though is to insure you have an excellant power supply to your coils and I don't mean pull out a voltmeter and and proble it to check for 12V either. You need a good scope to probe the power supply during coil firing. If you see more than a 0.5V drop when the coil fires you have a big problem. My Car had 2V drop !!!!!!!!! Old wiring/relays etc ass up to resistance that costs in voltage. I wired up a new relay in the fuse box to run my coil power feed directly and I now have a 0.2V drop when the coil fires. Makes a huge difference.

Hope this helps...

Mike

Hello Mike,

what did you excatly, to modify the relays and wire. I would like to do the same, but not sure how.

Thanks and best regards

vik

Hello Mike,

what did you excatly, to modify the relays and wire. I would like to do the same, but not sure how.

Thanks and best regards

vik

Get yourself a good 30A plus fused automotive relay and cut the +12V supply to the coils and connect it to a relay on pin 87. Run a high current wire from your alternator terminal and connect it to pin 30 on the relay. Ground pin 86, and connect pin 85 to where the coils used to get their +12V from (the loom). This allows much more current flow at the coil as there is less voltage drop across the length of the wiring in the loom.

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