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-   -   Need HEI help (https://67-72chevytrucks.com/vboard/showthread.php?t=480246)

TigerDMD 08-18-2011 12:08 PM

Need HEI help
 
purchased a rebuilt HEI for my 68 from Langdons stovebolt - I was told it was a fairly easy install. I'm going to list the first 7 instructions and see if someone can dumb it down for me so that I can understand - I think im in over my head.

1. Rotate engine to No. 1 cylinder firing

2. Set slightly before T.D.C. approx 10 - 18 degrees B.T.D.C

3. Remove old distributor

4. install HEI and assure full oil pump drive tang engagement

5. Rotate distributor until 6 points on internal star wheel line up with 6 points on stationary pole piece

6. Note location of rotor and install #1 spark plug wire at this terminal. Install other wires in clockwise direction proceeding through firing order 1-5-3-6-2-4

7. Power feed must be a #10 size wire direct from ignition switch to coil + terminal. delete any resistor either ballast type or inline resistance wire.

I honestly don't know what any of that means. Thanks for the help.

dmack91 08-18-2011 01:05 PM

Re: Need HEI help
 
OK, I will give it a shot.

1. Pull the distributor cap off of your stock dizzy and rotate the engine until the rotor is pointing where the terminal with the wire to cyl.#1 would be.

2. Check your timing mark. If you are between10-18 degrees TDC leave it, if past that, rotate back past 20, then slowly rotate the engine until between 18-10.

3. Just like it says.

4. Drop in the HEI. Make sure it goes all the way in as there is a shaft on the bottom that drives the oil pump. Generally, look at the old one, which should sit flush with the block when installed. Make sure the HEI is the same when installed (flush at the base where it meets the block - no gap).

5. Just as it says.

6. The rotor will be pointing at one of the plug wire attachment points on the cap when installed. This will be cyl. #1 now. Just wire the rest in the proper firing order, going clockwise.

7. Stock dizzy had a power wire with a resistor, either built in or possibly an external. This dropped the voltage going to the dizzy. The HEI needs full 12v, so you need to replace that wire with a 10 gauge wire without any type of resistor.

Good luck with the swap.

VetteVet 08-18-2011 01:45 PM

Re: Need HEI help
 
With Dmacks help and this you should be ok.

http://67-72chevytrucks.com/vboard/s...d.php?t=148346

doodah man 08-18-2011 02:25 PM

Re: Need HEI help
 
I did this for the first time recently on my truck and was also a little intimidated. In fact, this was the first time I even had to set timing on an engine so everything was new. To make it just a little more exciting, I drove the truck 300 miles to the in-law's house for the weekend and did the swap there. The only major problem I had was that the HEI was a tooth off when I finally got it back together. The truck started but sounded awful. I pulled the HEI back out, advanced it a tooth, and drove home the next day. It's not nearly as hard as it seems from reading all the how-to's.

That said, here's some more reading material:

http://www.oldengine.org/unfaq/hei.htm

http://www.pontiacstreetperformance....onversion.html

http://rmcavoy.freeshell.org/HEI.html

FLDBRED 08-18-2011 06:11 PM

Re: Need HEI help
 
Year One sells a plug in type wire that makes it even easier! It goes from the box on your firewall right to the dist.,this way you don't have to "splice" anything,it plugs right in on both sides.
Like the others have said,with your batt. disconnected just find top dead center,by watching your timing mark,when it is just about on zero pull your dist. cap off and see if it is pointing to the No.1 plug wire.When you install your new dist.you should be real close.

wilbilt 08-18-2011 06:34 PM

Re: Need HEI help
 
Remember that the distributor is driven by the camshaft, which turns at half the crank speed. You want to make sure that when you line up the timing mark on the crank that the distributor rotor is pointed at the #1 plug wire and not #6. If it is pointed at #6, rotate the crank one more full turn to line the mark up again and this time the rotor will be pointed toward the #1 wire.

In theory, you could just reinstall the plug wires and "make" the #6 terminal become the new #1, but the lengths of the installed wires might not allow this.

And it is nice to remain consistent with the 5 million other Chevys on the planet on which the #1 terminal is at the front of the cap rather than back toward the firewall. It could save someone some confusion in the future. Just my 2¢.

webfoot 08-18-2011 06:40 PM

Re: Need HEI help
 
Helps to put the cap on and make a mark on the distributor body directly under the plug terminal you want as #1. That way when you stab your distributor you can see a little easier if the rotor is right on or a tooth off.

johndawelder 08-18-2011 08:01 PM

Re: Need HEI help
 
Remember, #1 piston coming up on the compression stroke.


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