MSD Ignition for 97 LT1
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Teching In
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MSD Ignition for 97 LT1 Ok so just a brief history before I get into the meet and potatoes. A couple weeks ago I started having some bad misfires when operating under load. Typically the vehicle would be up to operating temperatures and under load (typically on the interstate) when I would experience the misfires. She only misfired a handful of times during city driving. I replaced the opti with the MSD distributor (PN 83811) after finishing the installation and testing her out, I was still experiencing misfires. I ordered the MSD 8.5 plug wires and the MSD GM dual connector coil under the assumption the coil was the correct fit. Turns out I ordered the wrong one. Yes, I understand OEM replacement coils for the later LT1’s are factory upgraded and I should have gone with one of those instead. Hindsight 20-20. BUT, I have been looking for an excuse to pick up the MSD 6AL (PN 6201) and I figured this may be just the reason to do it, if and only if the MSD universal wiring harness (PN 8876) will allow the coil to be compatible with the other ignition upgrades I’ve done. The dual connector coil doesn’t connect with the factory wiring harness, so if I get the universal harness and the 6AL, will it be compatible? The car is stock, but I plan on doing full bolt-ons within the next six months (including cam and valvetrain). Any help would be appreciated as I haven’t been able to find anything out and after contacting holley’s tech support over a week ago, I still haven’t heard anything. I understand the full ignition kit with the 6AL might be overkill considering my 97 Z28 is still stock, but like I said, I don’t plan on keeping her stock much longer. Thanks all!
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misfire "under load" is often due to plug arc which can be very difficult to "see". While Opti is often pointed at for any ignition issue it is certainly not always the case. The MSD Opti, unfortunately, has less than zero cred now and has proven to be bad out of the box in more cases than not over the last few years. Most common is your issue. IMHO before adding more aftermarket stuff like MSD box and coil I would consider putting back on the old opti "if" it was a real AC Delco one
If you are running the stock heat shields on the plug boots you should take them off and carefully look (read you will need to be able to get under car while it is running) and confirm you have no plug arc going on. You need to be able to "see" every part of every spark plug boot.
MSD does make a "adapter" harness to plug stock coil wire into it then to MSD box wiring. I have had the MSD 6A on for about 20 years now. It "may" help some in upper RPM but is certainly not a OMG this is amazing mod. The original Opti/coil on the 97 is fine on its own. The box won't hurt anything but should be the first thing you bypass if you do go with it when you do have ignition problems to rule it in/out of the equation.
If you are running the stock heat shields on the plug boots you should take them off and carefully look (read you will need to be able to get under car while it is running) and confirm you have no plug arc going on. You need to be able to "see" every part of every spark plug boot.
MSD does make a "adapter" harness to plug stock coil wire into it then to MSD box wiring. I have had the MSD 6A on for about 20 years now. It "may" help some in upper RPM but is certainly not a OMG this is amazing mod. The original Opti/coil on the 97 is fine on its own. The box won't hurt anything but should be the first thing you bypass if you do go with it when you do have ignition problems to rule it in/out of the equation.
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Joined: Oct 2006
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I had one on my L31 Vortec before the 24x swap. Seemed to help most at lower rpm and had better throttle response. With the multi spark at lower rpms it would fire a 16.5:1 air/fuel mixture in lean cruise without missing.
misfire "under load" is often due to plug arc which can be very difficult to "see". While Opti is often pointed at for any ignition issue it is certainly not always the case. The MSD Opti, unfortunately, has less than zero cred now and has proven to be bad out of the box in more cases than not over the last few years. Most common is your issue. IMHO before adding more aftermarket stuff like MSD box and coil I would consider putting back on the old opti "if" it was a real AC Delco one
TECH Resident
Joined: Oct 2006
Posts: 993
Likes: 173
From: Euless, TX
