Interesting note: 1350 engine and early TCI vacuum ignition.

[Pat Conlon]

Randy did a great job on my 1984 with his 1350 engine. Rather than going to a Dyna 2000 ignition, I left in my oem TCI vacuum ignition.

The early TCI FJ ignitions have 2 advance curves based on vacuum....not present on the later FJ with the DCI ignitions which have the advance curve hardwired into the digital unit.

The vacuum TCI ignitions have one wfo aggressive curve happening at low vacuum, and for cruising, a more sedate advance happening at higher vacuum. (with throttle plates partially closed) The vacuum reading is taken from behind the throttle plates.

My theory is that ..(it seems) with the higher vacuum levels caused by the 1350 pump the early TCI unit was always in the lower advance mode.....?

I found one of these Hyperpack DCI ignitions on eBay for $40 and plugged it in..... Holy smokes.... What a difference.
http://www.erd.co.nz/products/xjfj.html

[SlowOldGuy]

Shouldn't you get the same response from the stock unit by disconnecting the vacuum line to the ignition?

Or does the new ignition have a different advance curve?

DavidR.

[racerman_27410]

thats why i went with the Dyna ignition.... multiple advance curves so you can find the one your engine likes



KOokaloo!

[FJ1100mjk]

What was your criteria for settling on what your engine "liked"? I have a Dyna 2000 that came on my '87, that I will be getting running soon. It's stock except for a V&H exhaust system. I'm curious about how you went about finding the optimum advance curve setting.

Thanks.
Marty

[racerman_27410]

What was your criteria for settling on what your engine "liked"? I have a Dyna 2000 that came on my '87, that I will be getting running soon. It's stock except for a V&H exhaust system. I'm curious about how you went about finding the optimum advance curve setting.

Thanks.
Marty

By riding the bike using the different advance curves..... it was pretty obvious which curve my engine liked when whacking open the throttle. 

KOokaloo!

[FJ1100mjk]

 Thanks. Kind of thought that it might be a seat of the pants thing, but I thought I'd ask anyways.

Marty

[Pat Conlon]

Shouldn't you get the same response from the stock unit by disconnecting the vacuum line to the ignition?
Or does the new ignition have a different advance curve?
DavidR.

A good question David. If my theory is correct, that should work. No vacuum=low vacuum= more advance. That should work.
I had this Hyperpack laying around for a couple of years, and it is plug and play. I emailed ERD in NZ, questioning the advance curve they use on the FJ's, and they responded that they use the same stock curve that the later FJ DCI units are programmed with....with the only difference is that spark duration is longer.

Wow, this thing is alive now......

Frank, do you recall what advance setting you are using on your Dyna 2000... #3? 

[racerman_27410]

Frank, do you recall what advance setting you are using on your Dyna 2000... #3? 

yes sir.... it is indeed the # 3 advance curve on the dyna box.


KOokaloo!

[Pat Conlon]

Thanks Frank!