Dismiss Notice

Welcome To CK5!

Registering is free and easy! Hope to see you on the forums soon.

Score a FREE t-shirt and membership sticker when you sign up for a Premium Membership and choose the recurring plan.

HEI

Discussion in '1969-1972 K5 Blazer | Truck | Suburban' started by 69K5, May 24, 2002.

  1. 69K5

    69K5 1/2 ton status

    Joined:
    Nov 10, 2001
    Posts:
    1,544
    Likes Received:
    0
    Location:
    Monroe, LA
    who has put an HEI ignition in there first gen. I am getting ready to drop in my new motor and was doing some looking and it looks like I might need a BFH to get it to fit in the firewall. Just looking for some foresite if theres gonna be a problem. I have the stock HEI from a 75 K5

    thanks in advance

    nathan
     
  2. trukman1

    trukman1 1/2 ton status

    Joined:
    Mar 5, 2002
    Posts:
    129
    Likes Received:
    0
    Location:
    Ohio
    I'm running an HEI in my '67 but it's a big-block. Looked like it was going to be a tight fit but ended up going in just fine. I have heard they are tight fits with small-blocks but they do fit. Just be careful if your putting it into a 4x4 with plans to off-road it alot since body flex will likely trash the cap.
     
  3. Triaged

    Triaged 1/2 ton status

    Joined:
    Feb 21, 2001
    Posts:
    3,808
    Likes Received:
    0
    Location:
    CA (LA/OC area)
    I have a HEI in mine (installed by the previous owner). The ring that holds all the plug wires on (the part that most people just throw away) rubs the firewall just a bit. I have wheeled it hard (even with a front body mount missing...broke my fanshroud) and have not had any problems. I am going to do a tune up some day and plan on keeping all the old parts just in case.
     
  4. 69K5

    69K5 1/2 ton status

    Joined:
    Nov 10, 2001
    Posts:
    1,544
    Likes Received:
    0
    Location:
    Monroe, LA
    I dont have that ring either. I'll just be careful when we put it in. I dont do any major flexing like most people here. I just bounce through mud holes ususally. So i guess we'll wait and see. thanks for the help

    nathan
     
  5. chulisohombre

    chulisohombre 1/2 ton status

    Joined:
    Apr 11, 2002
    Posts:
    4,137
    Likes Received:
    14
    Location:
    Bangor,Pa
    i did a hei conversion with a accel super coil.the coil is larger than stock and i still had no problems.ive had the conversion for about a year now with a msd hooked up.i got about id say 5 to 15 more horsepower out of it
     
  6. 70jimmy

    70jimmy 3/4 ton status Premium Member GMOTM Winner

    Joined:
    Mar 3, 2000
    Posts:
    5,953
    Likes Received:
    248
    Location:
    Released from Pueblo, told I belong in Southpark
    I also did the conversion with HEI and supercoil. Beat the crap out of the firewall, it still rubs but no problems so far. Thinking about new motor, tranny and Transfer mounts. It was definately an improvement over points.
     
  7. MuddyMudSkipper

    MuddyMudSkipper Registered Member

    Joined:
    Mar 7, 2002
    Posts:
    49
    Likes Received:
    0
    Location:
    CA
    I had to beat the crap out of my firewall too. It fit before but the firewall was up against the cap and I was worried it would cuase problems any time the body flexed, so I whacked it with the hammer and now I have plenty of clearance.
    Jeff
     
  8. Steve_Chin

    Steve_Chin 1/2 ton status

    Joined:
    Mar 6, 2001
    Posts:
    1,126
    Likes Received:
    0
    Location:
    Foster City, CA, USA
    Ditto MuddyMudskipper... The distributor rubbed the firewall slightly so I had to persuade the firewall with a BFH to clear it. I staill can't get the distributor in or out of the engine without removing the cap first, and getting at some of the hold-downs for the cap are a pain in the behind. But, my Blazer already had the HEI in it when I bought it.

    If I were going to convert a Blazer with a points distributor over to electronic ignition, the only way I'd do it is to send the points unit off to David Ray and have him convert it to a small-body HEI. He uses off-the-shelf parts and custom machines the body so that if you ever have a failure any parts store will have the replacement parts in stock (unlike those Pertronix conversions). Dave can also put a custom curve on the distributor so that it works better with your engine too...
     
  9. 69K5

    69K5 1/2 ton status

    Joined:
    Nov 10, 2001
    Posts:
    1,544
    Likes Received:
    0
    Location:
    Monroe, LA
    thanks for the suggestion, but i already have the distributor. so i iwll just use a BFH to cure it.

    thanks for all the help everybody

    nathan
     
  10. ed rex

    ed rex Registered Member

    Joined:
    Oct 10, 2001
    Posts:
    63
    Likes Received:
    0
    Location:
    Penn Valley, CA
    I'd like to do this as well. In fact, was just about to make the purchase so's I have the goods in hand for this weekend.

    Other than the 'fit' issue mentioned, are there any other things to consider? As I understand it, the conversion makes a world of difference. Do you all agree?

    What is a good 'drop in' replacement? I was thinking of getting the Summit one....$149. Is this (and a set of wires) all I will need? Is it simply 'drop in and go' or is there a lot of fiddle-farting involved?

    With regards to the wires, any suggestions? 8mm? Bigger? Best bang for the buck?
     
  11. Robin

    Robin 1/2 ton status

    Joined:
    Oct 30, 2001
    Posts:
    184
    Likes Received:
    0
    Location:
    Georgetown, Texas
    I used Pertronix, as it's a step above the basic Summit one. I read an article in Super Chevy (I think) that was doing a 383 build and they liked it a lot.

    The feedback I got on wires was that MSD's Super Conductor 8mm are the best. I got the "roll-your-own" version so I could be picky about how I routed the wires. I used "Made For You" looms. Check out my pics of the setup (engine folder).

    Since the motor hasn't run yet, all of my advice is speculation
     
  12. ed rex

    ed rex Registered Member

    Joined:
    Oct 10, 2001
    Posts:
    63
    Likes Received:
    0
    Location:
    Penn Valley, CA
    Robin - Looking very nice....looks like your doing it right! I don't think I can route mine the way you are. Not enough room rearwards of the BB, firewall is right there. Also, that Petronics looks mighty tall....wonder if the Summit is a bit 'lower' or if the BFH clearance method will need to be employed. Thanks!
     
  13. Robin

    Robin 1/2 ton status

    Joined:
    Oct 30, 2001
    Posts:
    184
    Likes Received:
    0
    Location:
    Georgetown, Texas
    Yeah, I'm beginning to sweat the clearance issue. I really don't want to mess up the firewall
     
  14. Chris_T

    Chris_T 1/2 ton status

    Joined:
    Mar 17, 2001
    Posts:
    718
    Likes Received:
    0
    Location:
    Saskatoon, SK
    Another option on the Pertronix unit .. Crane cams has a "fireball" optical tigger set up to replace the points. I currently have this with the box mounted in the cab, an MSD cap and rotor for the points style distributor, an MSD coil and Taylor wires and I really like the set up. Been hassle free since day one and was a noticible improvement over the tired HEI I had in there to begin with. I replaced the HEI for clearance issues and have had no problems since
     
  15. Triaged

    Triaged 1/2 ton status

    Joined:
    Feb 21, 2001
    Posts:
    3,808
    Likes Received:
    0
    Location:
    CA (LA/OC area)
    If you are looking on buying a new (ie. not junkyard) dist. then don't get a HEI. MSD makes a drop in dist that uses a smaller cap and a external coil...that would be the way I would go. If you are just looking for cheep get a j/y HEI.
     
  16. ed rex

    ed rex Registered Member

    Joined:
    Oct 10, 2001
    Posts:
    63
    Likes Received:
    0
    Location:
    Penn Valley, CA
    I am definately looking at buying new. Is the MSD a points dist? I'm looking to get out of the hassle of dialing in the dwell as well as explore the 'noticeable improvement over points' comments that many have spoke of.

    What about the Mallory Unilite breakerless ignitions? Isn't that an HEI?

    Not looking for the cheapest route necessarily, but don't want to break the bank either. That's why I was considering the Summit HEI. Looked to be the right size for a 'drop in' fit and was only $150. The Unilites are just a bit more.
     
  17. Triaged

    Triaged 1/2 ton status

    Joined:
    Feb 21, 2001
    Posts:
    3,808
    Likes Received:
    0
    Location:
    CA (LA/OC area)
    MSD (as well as others) make smaller breakerless distributors. You can get a higher output with a external coil then a internal coil. In fact MSD makes a kit so you can use a external coil in a HEI. There are many out there...you just have to find one in your price range.
     
  18. ed rex

    ed rex Registered Member

    Joined:
    Oct 10, 2001
    Posts:
    63
    Likes Received:
    0
    Location:
    Penn Valley, CA
    Thanks! But now I'm confused. I've only had points systems. The other week I replaced the old coil with a MSD 'Blaster 2' coil. It was a round looking can the same as the old one, only it was red and supposedly had like '25% more output' than a stock coil. Upon opening the package, the fine print said 'for HEI ignitions' went on to say that if you use it with a points ignition, you have to use a ballast resistor, which I went and got. Based on this episode, I guess I assumed that HEI ignition likewise has an external coil. Your message says that there are more than one basic type of HEI? You can get a distributor with a 'built in' coil or one without? How would I know which is which? Are the 'breakerless distributors' listed as 'breakerless distributors' rather than HEI distributors? Other than that, are they essentially the same? Apologize if my questions are rudimentary, just haven't messed around with this part of the engine.
     
  19. Steve_Chin

    Steve_Chin 1/2 ton status

    Joined:
    Mar 6, 2001
    Posts:
    1,126
    Likes Received:
    0
    Location:
    Foster City, CA, USA
    Ed, there is only one distributor that can truly be called an HEI because that is a GM trademarked name (High Energy Ignition). All of the other non-points ignitions can be called by the generic term "electronic ignition" or "breakerless ignition."

    There are a number of aftermarket solutions (MSD, Accel BEI, Mallory Uni-Lite), as well as aftermarket conversions for electronic ignition. You will need to read up on each one if you really want to know about all of them.

    My thoughts on how I would proceed if I had a points distributor would be to have it converted and tuned by David Ray. My second choice would be to get MSD's electronic distributor. The reason I'd pick Dave over MSD is that he will put a custom curve and all sorts of options as you desire into the distributor so that all you need to do is drop it in, set the static timing, and fire it up.

    Oh, one more thing on converting from points to electronic: You will need to bypass the factory-installed pink wire that supplies power to the coil. It is a resistance wire and the electronic igitions will require a non-resistor wire to supply the power. Use a 12 AWG (or 10 AWG) wire run to the IGN terminal on your fuse box. I put factory connectors onto my power lead so that they'd lock into my HEI's cap, but if you're going aftermarket that point doesn't much matter.
     
  20. Racefreak

    Racefreak Registered Member

    Joined:
    Apr 1, 2002
    Posts:
    67
    Likes Received:
    0
    Location:
    San Antonio, TX

Share This Page