Rewire pic of HEI and single wire Alternator

[jayharrell]

I've been looking around for a couple of days, and can't seem to find any diagrams of what to cut out for a single wire alternator and where the best place to wire in a HEI distributor. Currently i've got a 455 buick motor in my 69 CST-10. Any ideas?? I yanked the wire harness out last weekend only to find all of it was mashed into the key switch. Seems this causes a few wires and connetors to melt, who'da thunk. Thanks guys

New to the forum by a week or so, great info on here.

[VetteVet]

You've got several options on either one of these projects. The HEI is normally hooked to the fuse panel at the terminal marked IGN UNFUSED and to the BAT terminal on the distributor. The terminal ends may be a problem, but use at least 12 guage wire and about three feet should do. You can fuse it with a 30 amp fuse if you wish.

Your other question might be more of a problem. I am not sure what you mean by "cutout". The one wire alternator only needs to feed the battery positive connection and the main fuse panel for the rest of the truck circuits. If you check the stock harness there is a soldered wiring connection where four wires are connected together. These wires feed the alternator, regulator the battery and the firewall connector, AKA the fuse panel connector. You could simply unplug the regulator and run the large red wire in the regulator plug to the large terminal on the back of the alternator. If you have not ripped out any of the stock wiring then everything should work fine EXCEPT You will no longer have a charging light in the dash. The brown wire and the blue wire on the regulator plug are the circuits for that function.
The electrical forum has a sticky post on the top that says WIRING DIAGRAMS FINISHED. Open that and scroll down to post 19 and you will find some excellent diagrams of the 67 to 72 trucks.

If you go to the top of the page that your post is on, right below the private messages box is a search box. Click on that and type One wire alternator in the box and click go. You will get two pages of threads and links to read. Then do the same thing only type HEI distributors in the box and you will get enough reading to keep you busy till supper LOL. HTH

[BCOWANWHEELS]

alternator is simple. run a wire ( #10 size ) from pst on back of 1 wire alt. to battery. if you want a amp gauge install it in series.
bob

[drman929]

I have no help to offer other than a question. How do you like the 455? How's the power?

[jayharrell]

Wells i've spent some time and looked around. I've mainly wanted to convert this harness to an "oem harness" for this truck with non facotry AC to one with a HEI dist, One wire altornator, and Factory AC upgrade. I've found all digrams. Thanks for the info on the 30 amp fuse. That seems to be the best way to go. Now to hack and cut and butt crimp like no tomorow. Just gonna take some time to sort it all out.

But anyway, as far as the motor, I like it. the BBB *big block buick* get about 19mpg and makes the one wheel wonder burn it to the ground when i stomp on it. But still cruses about 4500rpm on the hwy with a t400 behind it. The wider V in the V8 as aposed to the 350 or even 454 relaxes the motor.

I like to think of it as the USA it self, slow to rise, but when it does, LOOK OUT!!

Unfortunetly i have the 75-76 455, not the Stage 1 70, or 71-74 455 Elextra or Skylark. From what i've read this is when the emmision laws realy buckled down so in 75 they dropped alot of HP with oval port heads to bring it in under spec for the FEDs. But all in all it fills up the under hood and sounds great with some 3'' pipes out back. I might be cross foruming here.

I realy hate to even bring it up with the purist SBC and BBC purists. But this ol' white wonder came stock with the 396 CTS package, so i think the 75 electra 455 will hold its own and pay some tribute to the old timers out there. Or just get me banned from the forum.

I'll see if i can get a pic of bay attached.

This 3 day weekend i'm working on sitting down and figuring out this wiring blunder. I'll attach some pics when i get them.

Anybody have any time with a NON Chevy under the hood in these 67-72's???? What do you have, and what do you think???

[drman929]

Wow, 19mpg!!!?!?! What carb?

I am pretty sure I'm about to transplant a '72 455 into my '72. You have any pictures of your truck? I'm sure I'm not the only one who would like to see.

[jayharrell]

Just the stock QJ 4bl. I stripped all of the emissions crap off it. I have to pull the water pump this afternoon so i'll get some good picks.

That 72 is red isn't it???

[drman929]

Man, if I got that kind of mileage then I would sell my DD...haha

My '72 was med. bronze and white, but is now blue and silver.

[Pont406]

jayharrell,
I took 2 pics for you. One shows where I am getting 12v for the dist and wiring. I had HEI but switched to MSD. I could not get the right timing curve with HEI and I had spare msd set up laying around. Much easier to dial up timing curve with MSD. I am getting 14mpg city and 16mpg highway. I am not done tuning yet. I tryed 3310 holley and I could barelly get 9mpg out of it.

[jayharrell]

Well i spent last night reworking the diagram. I'm trying to pretend i know what i'm doing. LOL. Take a look. I've still got 2 wires that i will have to end or remove. But i think it will work. Take a look

Looks like i will loose one ground, one hot, and move the dist to the same line as the starter. Might not be a good idea i'm thinking, Might have to direct feed the dist.

[Longhorn Man]

runnin a cad 425 here, had a cad 500 but it was making death noises so i ditched it.
I agree with you, the torque in GM's BBB engines is awesome.
GM made some great truck engines, then put them in buick, olds, pontiac, and caddy cars. total waste.
That looks like a GM 3 wire alt to me... not a one wire aftermarket piece.
cad 500;


And the 425... not that one can tell them apart...

[Pont406]

Hey Andy,
Are you running stock radiator and fan with that caddy?

[Longhorn Man]

the fan is a stock fixed blade unit... I think a chevy piece, and the fan clutch is a caddy piece if I remember right.
The rad is a stock replacement for a G-20 van, 3 row core (most would call it a 3 core) with the bottom neck removed and the correct angled piece soldered in it's place.
So in essence, it is all stock stuff, just a little parts bin scrounging. (my parts bin is junk yards, but you get the picture)

I had installed an electric fan in front of the rad out of fear. Everyone always says how the caddy motors always run hot... however, I've seen the guage hit 210 once. In the summer heat, after just getting off the freeway (runnin 3000 - 3500 RPMs) it'll get over 200, but again, only saw 210 once. Once the truck is moving, it stays between 175 to 190.

I failed to mention in my original post, you me ntioned MPG... I don't have a working speedo/odometer in mine, the only time I mapped out my trip, I had gone to the west side of Dayton and back, which was about 70 miles each way. (I had it figured to the mile at the time) I kept it at 70 MPH (3200RPM) the best i could the whole way there and back, ran unloaded except a few hundred pounds of spare tire, and normal junk/tools and stuff I normally cary. I was also running VERY rich, watering eyes kinda rich, and I got 16 MPG. In town I know I only get 10 - 12 due to my right foot though.

[jayharrell]

Here a pic what i did to the old 455 today. I think i found the water leak. I only broke off 1 bolt, someone beat me to the other 3. Its always a bigger project then i expect. Live and learn.

I like that Caddy. My dad has a 78 Eldorado Convertible with the 500. Last year of the 500 and convertible. Only gets around 14 on a good day. But that was last a couple of weekends ago on the way up to Dever from Amarillo for a big biker swap meet. I think he said he only had about 1000 miles on the new rebuild so he hopes it to get better as it breaks in.

I figure i can just blow some piston rings and burn more oil, that should increase MPG of gas anyway. LOL

[BCOWANWHEELS]

andy,
will it smoke the tires ?????????LOL

[Longhorn Man]

Yep

[jayharrell]

Hey now, don't make fun of me just yet. It ran like crazy before i got the wild hair and tore i down this morning. Newbs are people too......