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Unread 06-12-2001, 09:54 PM   #1
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Join Date: Jun 2001
Location: Washington
Posts: 35
GM HEI upgrade?

I have a 87 YJ. I'm running a MSD coil and MSD 6AL ignition box routed through the old jeep ignition box. Can anyone tell me how to wire up a HEI ditributor with my MSD box? Can I cut the old iginition box out of the loop? Thanks in advance.

87YJ I-6 Offenhauser intake Holley 4bbl MSD 6AL box
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Unread 06-25-2001, 03:04 PM   #2
mike byrd
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Join Date: May 2001
Location: Wappingers Falls, NY
Posts: 7
don't bother with the HEI.... go to your local auto parts store and get a cap, rotor, adapter and wires for a '97 Ford pickup with the 300cu six'll be amazed and you don't have to modify ANYTHING. The distributor in your jeep is a motorcraft, the same exact one that's in the ford truck, except jeep used a smaller car that really restricts the spark/rpm..
'90 YJ, 4.2 liter, 4"Pro Comp Lift, lookin for other goodies.
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Unread 09-10-2001, 06:53 PM   #3
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Join Date: Sep 2001
Location: Delaware
Posts: 27
All you need to connect the HEI is a switchable 12v source and connect the tac wire. HEI can be expensive. $255 to $350.
87 Wrangler 4.2
Mopar MPI
4.0 Head
Throttle body spacer
K+N air filter

Con-ferr shackles,R.E. 4.5 lift with 33x12.5 BFG Muds and 1in. body
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Unread 09-11-2001, 07:06 PM   #4
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Join Date: Apr 2001
Location: n.c.
Posts: 51
what adapter are you talking about ?
89 sahara, 4.2 , k551 weber, nutter bypass, tuffy stereo security console & under seat security drawer, 4'pro comp & 3'body, front waggy44 w/detroit & 4.88, rear waggy44 w/detroit & 4.88, teralow sye, tw's cv drive shaft {rear}, warn locking hubs, boomerrangs all around, 35x15.50 tsl-sx swampers { love that roar}.
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Unread 09-13-2001, 09:19 PM   #5
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Join Date: Aug 2001
Location: minnesota
Posts: 12
When I had a 6 in my jeep I did a HEI swap it is hands down better then the ford dura spark crap. The idle was not choppy and the mileage increased. I got the dist out of an old 292 chevy motor then ordered the gear right from mopar. Had about $100 into the whole swap. I would recommend it to anybody with a carbed yj.
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Unread 09-18-2001, 12:34 PM   #6
glm 87 wrangler
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Join Date: Sep 2001
Location: Fayetteville NC
Posts: 271
cape cod conversions can help you out with the whole set up for about 220.00 dollars
They also have TFI kits. Dont know how well it works but there web site is very info..even tells how to install right on there site.Having problems with timming on mine.Just dont have the cash right now.Email He sells the thing and has all the info you need..May try the ford 300ci
trick first.
Gary 87 Wrangler 4.2 258 with weber carb and TFI upgrade.
31/10.5 and Nutter bypass!
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