Converting from tb-v to hei wiring?

[tfmech]

So finally got around to installing new hei distributer just had a couple questions about getting power to it. Got the tach hooked up and shift interrupt working. I am running a relay to provide power to to the new hei (yes it is a marine relay and the distributer is a marine dui hei). Which wire do I need to hook into for key switch power to turn on the relay?

 

[Bondo]

Ayuh,.... The purple wires are the Ignition circuit,....

Whatcha workin' on,..??

 

[tfmech]

It is a 89 Baja 210 sport with 2005 small block and drive, motor is about as healthy as the alpha drive can handle roller rockers, behive springs, air gap manifold, 650dp, dui hei, stainless risers, on aluminum manifolds, and a cam just nasty enough to make sound as mean as it looks.

I caught myself with it hooked to the purple wire. When I first got it installed with a makeshift setup so I could make sure it would start and I set the timing. It started right up but problem came when I went to shut it off it just kept on running. I had the modules unplugged but the old coil was still hooked up. I was thinking it might be back feeding through the old coil. I just wanted to make sure I was on the right wire to start with. I will try taking the coil out and see if that fixes it. Thanks for the help.

 

[Scott Danforth]

not sure what benefit you think you will get with the DUI over the stock TB-V ignition

you still need a shift interrupt switch

add a diode, you are back-feeding the ignition from your alternator excite wire

 

[tfmech]

not sure what benefit you think you will get with the DUI over the stock TB-V ignition

you still need a shift interrupt switch

add a diode, you are back-feeding the ignition from your alternator excite wire

Well I gave the tb-v the benefit of the doubt and tried it one time with the new setup figured it would at least run good enough to get the jetting right in the new carb. So it tried to go then it went lean plugs crispy white so I get it up still same problem good fuel pressure jet it up some more and more and then some more still lean. Finally got it to run with jets big enough to run a 700 hp big block plugs we're just starting to show color.

Doing some reading on tb-v the thing could have been seeing 45 degrees or more depending on which load window the thing wanted to run in and if the knock sensor was seeing knock or not. It also starts pulling timing to early for what I want to do. Which is great for a stock boat and stock motor, fuel millage....ect but not great for hp and if you running closer to the edge of what the motor and it goes lean or gets 45 degrees or more of timing bad stuff happens

Dui is good for as high as I want to spin it and I have control of the timing. Put it back to stock jetting and put the dui in and it already runs better. Problem is getting it stop running.

So.....diode in the exciter wire for the alternator. What size diode do I need and which one is the exciter wire? Thanks for the help!

 

[Scott Danforth]

5 amp diode is all you need.

You have to put the TB into base mode to set timing. Cant add more than 22 degrees to base because that is all the table goes to.

If you dont use a shift interupt, you will never get it out of gear

 

[tfmech]

I think I might have a five amp have to look.

I had it in base timing mode when I set it. I guess was I just supposed to leave it locked in base mode then it just gives a normal advance curve. Because the map in the book says there is no actual starting map and it can ad up to 35 degrees in mean best timing.

 

[tfmech]

Forgot to say shift interrupt is working it was easy just had to run it through it to ground the tach wire

 

[alldodge]

Lots of folks using the DUI and they even make a false statement in there sales pitch

The DUI?s coil and module only draw 2-3 amps. Most spark box ignitions draw anywhere from 6-10 amps.

If their unit draws less amps then there would be no issue. Then they go on and say you need a 12AWG wire to feed it.

In any case back to your question. Wiring a relay is easy enough, but since your motor was not shutting off and its a Merc I don't see it back feeding. I think you have something mis-wired