LS2 TRUCK / YUKON Coils - Discussion, Experience, Ideas, Pictures

[Dragon Humper]

http://www.dtec.net.au/Ignition%20Co...alibration.htm

That write-up has a great chart to show you why I think that hotwiring the coils is the way to go. You can dynamically increase your effective dwell even though the dwell time is fixed by the ECU. What do I mean?

If you use your factory coil (+) feed to charge the coils then you are short changing yourself on the amount of energy supplied to the coil in the time allotted. The factory feed has more resistance as well as less voltage, both combined limits the amount of energy put into the coil...especially at higher RPMs. By "hotwiring" the coils (feeding the + side from a relay directly from the battery, switched by the factory feed) the current avail. should be in the range of 1-2 AMPs and 2-3 volts more than the factory feed. This can increase the "effective" dwell from 3.5ms to 5ms even though the actual time allotted hasn't changed. Simply put, you can get as much work done in 3.5ms that would equal the work done in 5ms if you left the factory feeds in place and changed the dwell times in your ECU.

So if you can't mess with the dwell times, don't sweat it. Hotwire the coils and you will get a similar result. Not only will these coils give you more pop, as is, factory harness fed, they will function even better without messing with the ECU by simply feeding them battery voltage.




Jon.

[frankydodo]

Thanks jon! Im about to do the swap on my rb20! I will feed the coil with a wire directly from the battery with a relay !

Envoyé de mon SGH-I747M en utilisant Tapatalk

[steveo1502]

LS2 TRUCK / YUKON Coils - Discussion, Experience, Ideas, Pictures

We'll figured I'd post a couple pics of my coil swap, picked up a set of these from tryingtobebest a few weeks ago, I followed nimblestix DIY and it was super easy, I was kinda worried about the wiring but once you start it's really not bad at all

First I layed the coils out on a piece of wood, just to see how I wanted them, and make the harness on the bench


Next I got a piece of aluminum, drilled some holes


mounted with some smAll screwes and nuts



I mounted it on top of the fuel rail, made some little brackets



Cut some little notches for the wires so I could still run the stock cover





I ran the +12 v power for the coils straight from the battery through a relay, I also didn't like the little bolts and nuts I had there so I cut some little pieces of pipe to cover each one and painted black, and took each coil out of its bracket and painted the brackets .



That's it

[AL91GTR]

I finally got around to wiring my LS coils directly through a relay. Ran through a 30 Amp fuse and it's hard to tell for sure, but the old seat of the pants says it actually seems to idle and rev even smoother than before if that's possible. Tough to say for sure while it's on jack stands ha

[frankydodo]

Can someone tell me the center distance from one spark to another? I want to make a bracket for the coil but i dont have my car for the winter :*

Envoyé de mon SGH-I747M en utilisant Tapatalk

[Bruizer]

not a great pic but some nice coils anyway. Stock location.

[steveo1502]

They aren't spitfire... Okada plasma

[steveo1502]

At least I think they are, remember him posting about them a while ago

[judasentinel]

Old thread revival....

How do you run the coils directly from the battery with a relay? I want to learn what kind of a relay and how to connect it. Any resource for that info? Does this require me to have to run a wire to the ignition switch in the car? How will the relay know when to turn on? I can connect things but I guess I dont know how and what to connect.

Any specific size/spec relay and fuse required to do this?

[steveo1502]

I used 30 amp 5 wire relay from princess auto, yes ignition wire turns on the relay

Sent from my SM-G900W8 using Tapatalk

[Shane_Sawatzki]

Pin 86 - Existing power source to coils
Pin 85 - Ground
Pin 87 - Fused 12v connection to battery
Pin 30 - Power output to coils.

should do it

[judasentinel]

Shane, how did you connect the ignition to the relay? Is there a wire I can tap into, within the engine bay of an R33 GTR?

[AL91GTR]

You take the factory power to the coils (at the 2 pin connector) and use that as the trigger for the relay. Then run power from the relay to the coils. Just like Shane said above and I did mine this way also a few years ago ... works great.

[judasentinel]

So the 2 pin connector gives 12V and a trigger as well?

Or do I still need to run the 12V directly from the battery to the relay?

I wish there was a diagram to follow.

Does crappy tire sell any relays I can use? Any specifics to look for?

[Shane_Sawatzki]

the 2 pin connector has a 12v and a ground I believe.

your trying to achieve a stronger 12v direct from the battery.

you use the 12v in the 2 pin connector to trip the relay to pull power from the battery, instead of using the 25 year old wire running through your engine harness to power the coils.

so pin 86 is the existing 12v power in the 2 pin connector.