MSD 6A vs. HKS Twin Power
 

Ever since I installed the MSD 6A on my car it has had a slight miss at idle. Kind of like; mmmmmmmmmm,boom,mmmmmmmmmm,boom,mmmmm.... you get the idea.

Note: The MSD fires just the leading TII coil. The Twin Power fires both leading and trailing.

I have both a MSD 6A and a HKS Twin Power wired for use so I decided to do a little experiment with my Gtech Pro, (and yes i know the Gtech reads low and does not account for aerodynamic drag).

These runs were done on the same afternoon with the only difference being that I added 100lbs. of fuel before the green and blue HKS runs.

Barry


http://i287.photobucket.com/albums/l...es/gtech-1.jpg

Nice info Barry!

What plugs were used on the runs? You don't happen to have figures with NO amps whatsoever do you?

:)

Classicauto,

I am using BUR9EQs all around.

Without an amp the spark would blow out with about 8 psi. and would not rev to 6000 rpm without a heavy stumble.

When I first put the Twin Power on I was amazed at how smoothly it ran.

Maybe if three MSD 6As were used, one for each coil, it would be comparable in power and smoothness.

Barry

The reason the twin power idles so well is because it uses a transistorized ign circuit for the lower rpm ranges (which has a far longer burn period compared to CDI) even when CDI is utilizing multiple restrikes at stupid high current and voltage it will never match the clean burn and stable burn ability of Transistor ign system and especially boosted ones.

Here is a plot of a custom CDI system I engineered/tested, its of massive output and specification, but still a smoke packet sized HKS unit outshines it at low engine rpm ;)

http://img297.imageshack.us/img297/9273/rrcditest.jpg
Burn time is roughly 420us or .4 milliseconds and there is 6 separate restrikes at 1000rpm over roughly 5 milliseconds per cycle. System pulls about 25 amps of first spark and 13 amps for the restrike sparks.

Even at high rpm's and mid range the only time the CDI will shine is under high duress (heavy AFR and water injected for example), though many people can complain of a power loss on CDI systems. You only need to look at current F1 technology its a 50/50 split between CDI and Transistor systems! The HKS box employ both systems in their tiny case.

It is s great unit.

rice have you tested the upper limits of what the HKS twinfire will ignite on water injection? i already have the HKS unit not installed but ill be adding water inj shortly running hopefully 20-25psi on a t66. and with the amount of water i will be running possibly 700+cc both pre and post turbo i was looking at the possibility of needing a CDI at the upper range. iv been looking at making a M&W pro14r based system if i need to though. but being that i already have the HKS for streetability i wouldnt mind using it if itll ignite the charge.

z

I run ~1.40kg/cm boost (~20psi old money) in my own car with Water Injection and the HKS box.

*Plugs need to be gaped at or less than 0.020"
*Water rate of 20% to fuel injection rate at peak revs is maximum I have found you can run (mid revs can take up to 40%)
*AFR ratio needs to be 11.3:1 or higher
*Spark advance needs to be around 13 deg after peak torque or more depending on your engine

If anyone of those parameters are out you will find it will be down on power allot (you may or may not even feel the misfire let alone hear it).

50/50 by weight mix of methanol to water allows more power and running of a richer mixture (10.9:1) not only will you get more power but it will have a lower EGT as well (this is what I use now, after testing the differences just this week).

Hope this helps.

excellent exactly what i was looking for. thank you lol saves me money... for now atleast till i get power hungy and run more

z

It's a little off topic, but would you be able to post up some incremental acceleration data like the following format (of your set up?) and detail it a bit more... how much boost etc etc.

http://www.ausrotary.com/viewtopic.p...tech&start=120

This is a stock standard 13B-REW with stock twins on 0.9bar boost
http://img213.imageshack.us/img213/8...respeed1nw.jpg

I'd love to know how long it takes your car to do 100kmh to 200kmh, if you have this on file or can test it for us.

Rice,

I have a question for you.. I been a fan for twinpower for a long time.. I'm debating what to do when I do a 3 rotor set up. What would you recommend?? Is there a way to run twin power (maybe using 2) to run it on a 3 rotor?? your thoughts please :)

http://www.riceracing.com.au/Videos/ricesp.mpeg

^ You can see the old G-Spot RR in action :driving: Car now have over 100bhp more than in that video :driving: and use a Race Logic VBOX3i which is 1 trillion times better, but the old G-Spot was a fun tool to use and pretty handy if set up properly *read not trying to cheat yourself lol*

Peter, i have noticed improved performance, and idle using the newer digital 6 and digital 7 MSD boxes. have you played with these at all? The HKS twin power boxes seem to be good to the 600 hp range in my experience, which should suffice for most guys..

That sounds great :)
I have not used those, but have pretty much every other CDI based unit and they do not work as well.
If you had access to a scope would be great to see how long the burn time is on those new units from MSD? Longer spark burn (inductive ign) 100% suits rotaries more than "energy" and multiple discharges.. for low rpm's anyway.
I do have some other devices I am experimenting with and using right now which work a treat, but as I am getting old and wise I don't share 1/100th of what I used to on forums (people just copy it and claim it as there's lol)... when I am over it and onto the next better thing I'll let you know about it (Honda F1 style yo!!!)