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Old 11-22-2001, 06:24 PM   #1
Longhorn Man
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Post HEI swap

A REAL EASY, CHEAP, AND PRACTICAL UPGRADE YOU CAN DO TO ANY OLDER G.M. VEHICLE, WOULD BE TO DROP IN AN H.E.I. DISTRIBUTOR OUT OF A MID TO LATE '70'S CHEVY.
IT'S A STRAIGHT FORWARD SWAP, THAT IS ALMOST AS EASY AS PULLING THE OLD AND DROPPING IN THE NEW. ABOUT THE ONLY THING TO REMEMBER WHEN DOING THIS, IS THAT IN ORDER FOR THE H.E.I. TO WORK PROPERLY, IT WILL NEED FULL SYSTEM VOLTAGE. THE WIRE GOING TO YOUR COIL WILL NOT SUPPORT THIS KIND OF LOAD. THE BEST WAY TO DO THIS, IS TO PLUG THE HEI FEED WIRE INTO THE IGN. UN FUSED LOCATION ON YOUR FUSE BOX, AND RUN THE NEW WIRE OUT TO THE DISTRIBUTOR. WHILE DOING THIS, THE YELLOW WIRE GOING TO THE STARTER CAN BE DELETED ALSO. THE 2 WIRES CAN BE SNIPPED, OR TAPED AND TUCKED AWAY.
ONE OTHER THING TO REMEMBER WHEN DOING THIS, IS YOU WILL NEED A NEW SET OF PLUG WIRES. FOR A FEW BUCKS MORE, YOU CAN HAVE HIGH QUALITY WIRES THAT WILL GET ALL OF THE NEW FOUND POWER TO YOUR PLUGS.
FOR A LITTLE MORE POWER AND ECONOMY, PUT IN A HOTTER COIL AND AN AFTER MARKET ADVANCE KIT.
THIS EASY MODIFICATION WILL REWARD YOU WITH EASIER STARTING, BETTER GAS ECONOMY, AND LONGER PLUG LIFE. NOT TO MENTION THAT YOU'LL NEVER HAVE TO MESS WITH THE POINTS SYSTEM AGAIN.

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Old 03-29-2002, 08:30 AM   #2
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To keep info on HEI in an easy to find spot I'm adding this info posted by members regarding HEI.

bigjimzlll: I bought a proform HEI..its a hi performance..higher volt coil..better advance curve..low saturation module..they cost about a 150.00 ..thats a brand new bolt in set up...its a simple install...just run a #10 wire from the unfused ignition terminal on your on your fuse block to the HEI..do away with the resistor and wire from your starter to the old distributor..and new plug wires.

Fast68Chevy: any HEi distributor on any chevy V8 without the extra 4 pin flat wiring plug will work, make sure it has the vacuum advance diapragm on it(not ESC controlled in some of the 81-up vehicles such as camaros firebirds pickups, etc) caprices and impalas and such didnt have that stuff tht Ive ever seen.

Run new feed wire form instrument panel fromt he ign unfused port, and use inline fuse, and do away with the old white wire that goes to + on the coil and also do away with the yellow wire thjat goes to + on coil and goes from there to R on the starter solenoid.

Project1970: Everyone else already got it as far as the install (just in case - you need new wires, of course) but as for what to expect when you get it done...well, when I did mine...I got a better idle, easier starts, and - the best part, and I've got numbers to back them both up! - a boost of nearly 20hp (191 to 208) and 2 miles per gallon (from 7.7 to 9.7!!) - and I still haven't regapped the plugs for HEI. I'll probably pick up a little more all around once I widen the gap to .045 or so.

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residing near Rose Hill, Kansas

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Old 04-10-2002, 10:42 AM   #3
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BigJackDaddy posted the following diagram

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Old 12-18-2002, 03:42 PM   #4
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This is quality information here. I wanted to respond to keep the post going.
I switched to an HEI and I couldn't believe the difference.
To hell with the points type.

Thanks for the diagram.
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Old 12-23-2002, 05:27 AM   #5
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HEI-- Cent & Vac advance

I purchased my H.E.I. unit from a firm that specializes in distributors, re-building ; including H.E.I. I was told they would calibrate the unit to factory specs or what I might desire...
I furnished the specs as outlined in the GM Service Manual for a 402 engine. Centrifugal advance - - [ degrees] ( 0 @ 930 RPM )
(2 @ 1260 RPM ) (16 @ 2400 RPM ) 30 @ 4400 RPM). GM also specifies ( 0 degrees vacuum advance @ 8" Hg ) ( 20 degrees vacuum @ 17" hg ). Purchased a new vac advance as old one was not in calibration.
I installed the distributor on the engine and set it up per previous stated specs. I also have another reference which, I believe is a great cross check and is not difficult to accomplish!...
This manual "1971-80 Tune-Up Specifications" published by GM-AC-Delco ( Man # SD-100 ) This reference states that centrigal spark advance @ 2000 RPM should be 10-13 & total advance ( incl. vacuum) should be 28-35.
So, I dialed in the timing lite 32 degrees; set engine speed at 2000 read on the "0" mark on the c/shaft damper timing indicator.....
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Old 01-12-2003, 10:44 PM   #6
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Does anybody know..can I get a HEI from a 250 6cyl and use it in my 64..Think I got a 230 CID
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Old 05-08-2003, 10:07 PM   #7
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I used a 65 Chevy II distributor and coil when I broke my 77 6cyl. distributor shaft.
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Old 11-02-2003, 01:47 PM   #8
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i have always had HEI, but am thinking of getting the hotter coil package i see in summit. i didnt know it helped gas milage.....
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Old 11-02-2003, 03:53 PM   #9
Longhorn Man
its all about the +6 inches
 
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It does...but you will never see the increase, to say it is minimal is an understatement.
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Old 01-29-2004, 01:07 AM   #10
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if im going to run my pink hei wire from the ign unfused port... do i need an inline fuse?
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Old 01-30-2004, 10:39 AM   #11
Longhorn Man
its all about the +6 inches
 
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Yes you will.
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Old 09-19-2004, 09:22 PM   #12
67ChevyC10Stepside
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what is this ign unfused port? does it say that on the fuse block? so i just drop HEI in run wire from there to the HEI and im done? what can i do to the HEI to make it better? the one i have is just stock as far as i know.
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Old 09-23-2004, 09:51 PM   #13
Longhorn Man
its all about the +6 inches
 
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Stock is fine. higher output coils do little tro nothing in stock or stock-ish engines. (dynos don't lie)
Ignition unfused is a terminal in the fuse box, if the print is still readable, then it'll say it...if not, I can post a pic of it when the attachments are up and working.
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Old 01-28-2005, 05:09 PM   #14
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what about the fact. tach hook up?Do you hook it the the neg, side of the coil?
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Old 01-28-2005, 06:33 PM   #15
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My HEI cap has a spade for the tach hookup. It's right beside the hot wire for the coil.
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Old 01-29-2005, 11:53 AM   #16
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sounds like an easy swap.The truck wont have any more performance power will it? It just gets rid of those problem points ,right?
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Old 01-29-2005, 09:09 PM   #17
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hei swap

I have a 80 GMC and it has no points. I am wondering if I have a HEI distributer system.
marvxyz Pittsburgh Pa.
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Old 01-30-2005, 12:22 AM   #18
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Quote:
Originally Posted by marvxyz
I have a 80 GMC and it has no points. I am wondering if I have a HEI distributer system.
marvxyz Pittsburgh Pa.
Yeah, your 80 should have had HEI. They quit putting points on them in the early 70's.
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Old 02-07-2005, 02:26 AM   #19
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I have a 71 k20. Do I have HEI. How can I tell? I'm having starting problems, and I dont understand why. When did they start using HEI factory.
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Old 02-07-2005, 02:27 AM   #20
67ChevyC10Stepside
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hei is real big and has coil in the cap.....points is just big enough for all the plug wires..
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Old 02-07-2005, 03:35 AM   #21
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Here are some pics I got from Ebay.
First is points type dizzy.
Second is HEI
Attached Images
  
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Old 03-17-2005, 01:45 AM   #22
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What size inline fuse should you use for the wire from the firewall? thanks
Ryan
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Old 03-17-2005, 02:14 AM   #23
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can anyone post where the unfused terminal would be on a '74, i cant read a thing off my fuse block
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Old 04-17-2005, 05:00 PM   #24
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Quote:
Originally Posted by ryanroo
What size inline fuse should you use for the wire from the firewall? thanks
Ryan
I would also like to know what size inline fuse to run to the H.E.I.
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Old 05-02-2005, 10:20 AM   #25
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Quote:
Originally Posted by 1978steven
I would also like to know what size inline fuse to run to the H.E.I.
Me too. I just picked up a HEI and am eager to get it hooked up.
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