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Old 03-29-2013, 04:27 PM   #1
1972SUPERSB
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HEI Conversion Questions

I will converting my points igniton to a HEI soon and had some questions. Which spark plug wire set do yall use? I have heard of using 1975 corvette wires and 1978 corvette wires? I have the stock ramshorn manifolds. Also do I need to change my spark plugs out. I have the stock ac delco in there now. From what ive read looks like my stock tach should work as well. I will also run a 10 guage wire to the fuse block marked unfused ignition which i think is correct. Thanks
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Old 03-29-2013, 04:59 PM   #2
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Re: HEI Conversion Questions

Use a set of wires made for HEI. I,m running taylor wires If the plugs are good leave them in just set gap to .045 and your 10 gauge will work or 12 will be OK also. check to make sure you have power while cranking and in the run position for the HEI...Have fun
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Old 03-29-2013, 05:14 PM   #3
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Re: HEI Conversion Questions

^^ Agree with the above. IIRC, standard plug wires are 7mm and wires for HEI are 8mm (or larger) and they are required. Not sure about Corvette wiresets, and I don't recall which wires I used for mine w/HEI. Use the same plug type as your stock plugs. I would use 12 ga. wire, as 10 ga. is just a bit too large and cumbersome IMHO. I know others have used 10 ga., it's just not my personal preference.
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Old 03-29-2013, 05:47 PM   #4
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Re: HEI Conversion Questions

Plug wires from a 76 Vette works they were HEI with ram horn exhaust. Bought a set from Autozone for $20 they work great perfect length.
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Old 03-29-2013, 05:48 PM   #5
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Re: HEI Conversion Questions

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Plug wires from a 76 Vette works they were HEI with ram horn exhaust. Bought a set from Autozone for $20 they work great perfect length.

Good to know. Thanks!
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Old 03-29-2013, 06:01 PM   #6
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Re: HEI Conversion Questions

Quote:
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Plug wires from a 76 Vette works they were HEI with ram horn exhaust. Bought a set from Autozone for $20 they work great perfect length.
I can also verify this first hand. That's the application I use when converting to hei and they fit well with rams horns.
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Old 03-30-2013, 09:17 AM   #7
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Re: HEI Conversion Questions

subscribed.
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Old 03-30-2013, 10:48 AM   #8
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Re: HEI Conversion Questions

Once I get all of it installed I will take some pics of wire routing. I will be replacing intake manifold at the same time
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Old 03-30-2013, 10:56 AM   #9
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Re: HEI Conversion Questions

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Originally Posted by Tx Firefighter View Post
I can also verify this first hand. That's the application I use when converting to hei and they fit well with rams horns.
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im doing the same but my motor is a 396,
Q- (same application?)

Q- are the hei distributors the same for big and small blocks? i just picked mine up, they said from an 82 blazer, i presume a 350? if so, will this dist work in my 396?

getting diff answers in the outside world
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Old 03-30-2013, 11:04 AM   #10
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Re: HEI Conversion Questions

Yea you can use the same distributor for small blocks and big blocks
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Old 03-30-2013, 11:26 AM   #11
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Re: HEI Conversion Questions

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Yea you can use the same distributor for small blocks and big blocks
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thanks.

thats what i get for asking folks at (tunex). if i need a reliable answer, i will ask you guys,
tunex dorks..
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Old 03-30-2013, 11:50 AM   #12
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Re: HEI Conversion Questions

Quote:
Originally Posted by phil2013 View Post
im doing the same but my motor is a 396,
Q- (same application?)

Q- are the hei distributors the same for big and small blocks? i just picked mine up, they said from an 82 blazer, i presume a 350? if so, will this dist work in my 396?

getting diff answers in the outside world
In your case, buy plug wires for something like a mid 80s big block pickup. Big blocks used very similar exhaust manifolds between early and late trucks and same style of wire routing ( over the top of the engine). The small blocks are the different one since they used radically different manifolds and wire routing between the early and late style of trucks.
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Old 03-30-2013, 11:54 AM   #13
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Re: HEI Conversion Questions

Quote:
Originally Posted by Tx Firefighter View Post
In your case, buy plug wires for something like a mid 80s big block pickup. Big blocks used very similar exhaust manifolds between early and late trucks and same style of wire routing ( over the top of the engine). The small blocks are the different one since they used radically different manifolds and wire routing between the early and late style of trucks.
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my 396 (does have) the ram horn exhaust manifolds. just didnt' know if there was a big difference
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Old 03-30-2013, 12:02 PM   #14
Tx Firefighter
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Re: HEI Conversion Questions

I've never seen a big block with ramshorns manifolds. Are you sure they are ?
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Old 03-30-2013, 12:08 PM   #15
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Re: HEI Conversion Questions

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I've never seen a big block with ramshorns manifolds. Are you sure they are ?
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they sure as hell look like stock ram horns to me, i will try and post a pic
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Old 03-30-2013, 12:13 PM   #16
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Re: HEI Conversion Questions

my bad, taking another look at them they are not ramhorn manifolds, duh.

thanks for your help!
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Old 03-30-2013, 02:06 PM   #17
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Re: HEI Conversion Questions

The center exhaust ports are not together on a big block, no ram horns.
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As for reading directions...
The directions are nothing but another man's opinion.
Learn from the mistakes of others, you won't live long enough to make them all yourself...

Bad planning on your part does not necessarily constitute an instant emergency on my part....

The great thing about being a pessimist is that you are either pleasantly surprised or right.
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Old 04-04-2013, 12:07 PM   #18
1972SUPERSB
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Re: HEI Conversion Questions

I have another question. I already ran my wire from the ign unfused terminal to the BATT on the distributor. Now I have the old yellow wire from old coil. Can I just cap this off? Also I understand this yellow wire goes to the starter as well. I noticed the purple wire was never hooked up to starter but truck has always started fine. Do I disconnect the yellow from starter and connect purple wire? Thanks
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1972 Cheyenne Super SWB 350, Auto, Bucket Seats w/Console, Tach, Factory A/C, P/S ,P/B, Tilt

1998 Chevy 1500 Ext Cab 5.7, Pewter w/blue interior
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