Getting the last few things ready to start the conversion and am curious about the electrical conversion.

What is needed to modify the stock '74 electrical system to work with the 911 engine. I assume the Fuel pump + lead will come from the engine bay realy board.

I have a crane ignition system (Hi-6, XR-700, and PS-91 coil).

Thanks.

There are only a few simple mods you will have to make. The biggest one is the wiring off of the alternator. There are 4 leads that come off the back of the alt.

B+
D+
D-
DF

The B+ goes down to the starter (big bolt terminal)

The other three simply use the 914-4 volt reg and just mach them up. Now for the trick, you can pull off the volt reg on the 914-4 circut board to find out which one is which, when you do that, the terms are flipped on the other plug on the circut board. It is hard to explain without drawing a picture. I know I did somewere on my 914-6 thread, flip through it. Other than that, I think the fuel pump wires go dead because there is a sensor tied into the engine (type 4 FI) that kicked power to them. I used a different power lead.

The oil idoit light wire is green/grey I think?

You use/modify the 914-4 wirring harnes. Shorten a few wires, lengthen a few if needed sort of thing.

ANother tricky one is (if I remember right?? ) the wires that go to the coil are both black, so test which one comes live for the coil + term, then the other one is for the tach.

Wirring is on this page:

http://www.914world.com/bbs2/index.php?act...2&t=15282&st=60

Thanks...

No problem! I love it when a six comes together!

The last three cars I did had internally regulated alternators, and the fuel pump was relocated up front so I removed the relay board, and make the 6 harness to connect right to the fourteen pin connector that plugs into the forward part of the chassis harness. Makes for a clean install. These were all carb'd engines though.

Kerry's is a carb'd engine so this would be an option for sure. Little more work, but cleaner engine compartment.

Well, if you're using a Motronic FI, it's a little more complicated...

spagetti

If you keep the relay board just ground the terminal in the picture and your fuel pump will run stock relay/fuse. Good place for anti theft device too.

front left (outside) spade of 4 spade injection plugin.

Hows about CIS? I can't wait.

"I" jumpered the relay board and used the CIS fuel pump....

I like the idea of getting rid of the relay board. I guess I will look at the board diagram and see what I need to keep.

Should I cut the connecters off and solder/heat shrink the wires or ?

Cheers
Kerry

QUOTE (Kerrys914 @ Dec 20 2004, 04:25 PM)

Should I cut the connecters off and solder/heat shrink the wires or ?

No, that would definately constitute a hack job!

You spend the $18 or whatever it is now and get the mating 14 pin connector.

My car still has the relay board as well, but I wouldn't mind getting rid of it since it doesn't do anything.

Definitely a good idea to move the fuel pump up front out of the heat and road hazards/dirt, since you're doing all the other major stuff anyway.

Sorry for the pre-dip condition of the engine bay.

Since my oil tank is in the front, I made this to replace my relay board. It's a breather box.

I'm a fan of removing the relay board if it's not needed because it's a breeding ground for electrical problems.

This is sooo cool. All these six-miesters trying to get it done.

I'll be following this one for sure...

KT

Oh man, here's a way better picture.

Isn't it neat without the relay board and all new wiring.

Don't want a hack job here I just figured it I make a clean hard soldered connection and re-wrap it that would be better then some sort of connector. The car is not going back to a 4 so there is no worries about putting the board back.

What are the details on this 14 pin connector (part number and photo)? Does it connect the 14 and 12 pin connectors together?

I was looking at the relay board wiring diagram and can see that the two pin connectors just need to be connected together. Is this correct?

I assume this 14 pin connector would just allow the two to just be connected.

I took the route of buy a wiring harness from Patrick.
I describe to him what I wanted to accomplish,and they made the harness accordingly.
I had them make it so I did away with the relay board completely.
It was an easy plug-in deal.About 400.00 I think.
Came w/an interface for the tach & fuel pump.

Don't know if this helps,but it was a clean install for me.

Ron

Getting rid of the relay board is something I have never done. I have always gone with "Touch as little as possible" when doing conversions. But wow, I sure like the thought of getting rid of all that mess over there! I might try it out on my own six this winter, just for fun.

What I do is make a new engine wiring harness, using the connectors off the 911 engine, all new wires, and then heat shrink it all, with a very OEM finished look.

I've made five engine harnesses like this, three for in house conversion projects, and two for other guys, who wanted a "plug and play" harness. PM me if this is what you are looking for. You plug the harness into all of the connections on the engine, install the engine, and then plug the male and female 14 pin connectors together. Clean and neat, factory appearance, no problems with old wires, etc. All of these were for engines that had internally regulated alternators though, so if you've got a externally regulated alternator, then you may want to retain the relay board, or provide for a different kind of voltage regulator.

Deleting the relay board cleans up the engine bay, as well as making access to the oil filter much easier.

I'll have to search my pics to see if I've got any detail from the last project I did.