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What does a HEI/ESC control

jeff l

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I am taking a 305 out and puting a 350 in, I think I can connect every wire/senser, but the wire going to my old Q-Jet

These are options
1 Put Hei in and connect every wire
2 Put Hei in and do not connect 2nd set of wires
3 Convert my Hei/esc to regular Hei ( I heard you can cut wires and conect others)

4 Buy new just Hei

I just don't know much about HEI/ESC and what it controls and what would I lose if i don't have ESC. and what would it do to the computer

Thanks
 
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The only thing to installing a regular HEI is to drop in the distributor and connect the power wire .

Mine is like that , the ESC wires were cut , the ends saved in my tool box , and the wires stuck in the harness conduit taped up .
 
pauly383k10 said:
The only thing to installing a regular HEI is to drop in the distributor and connect the power wire .

Mine is like that , the ESC wires were cut , the ends saved in my tool box , and the wires stuck in the harness conduit taped up .
So you had a HEI/ESC and just cut the ESC wires off and every thing was ok
Did you lose anything?
 
IIRC, you can't just cut the ESC wire, it will permentaly retard your timing. I can't remember the procedure, but I think you need to jumper 2 wires on the dist-to-esc module connector on the distributor side.
Do some searches on google for esc bypass or esc disable, i did this many years ago attempting to troubleshoot a problem.
 
jeff l said:
So you had a HEI/ESC and just cut the ESC wires off and every thing was ok
Did you lose anything?

You didn't get what I said . I dropped in the HEI distributor i.e THE WHOLE NEW DISTRIBUTOR . Which requires just a power wire .

This obsoleted the resty of my wiring !!

The ESC/HEI distributor is in a box in my garage . I refuse to let it get within 3 feet of my truck .
 
There are three options:

1) Run the ESC and hook everything up like it was on the 305.

2) Convert the distributor by replacing the 5-pin module with a 4-pin module (available everywhere) and replacing the one harness (also available at many parts stores).

3) Convert the distributor by bypassing the ESC module. You just have to jumper the green and black wires together (pins A and C in the 4-way weatherpack connector).

For either option 2 or 3, you don't need the ESC module that came from behind the glove box. You can remove the harness by taking off the "piggyback" power connector from the distributor hot lead. There is also a ring terminal to ground which attaches to the passenger's side head.
 
When I converted mine I replaced the pick-up coil to the older style to work with the 4 pin module. If you jumper the wires does that eliminate the need to convert the pick-up coil? If I'm not mistaken, the harness from the pick-up coil has the 3-way connector for the 3-pin side of the ignition module.

I went through 2 ECM's before I converted. That was about 8 years ago and I haven't had an ignition problem since.
 
yeah I just dropped in a whole distributor... I had one sitting on the shelf, and the new, rotor, cap, and coil I had installed on the old one swapped right over.

I decided to get rid of the ESC when I accidentally left the ESC wire off and the truck wouldn't start, couldn't figure out why it had no spark.... Until I found the wire crammed down between the bellhousing and body.
 

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