madden87 Posted December 21, 2008 Share Posted December 21, 2008 I have an HEI distributor and I think I messed it up. A couple weeks ago I went to the track and on my first pass I ran 12.5 with no problems. On my next pass I ran a 12.8 and it sounded like popcorn under my feet (exhaust was removed). I drove it home from the track and it was fine, but when I took it out to test it the next day I found out the problem only occurs at higher rpms. I have been told that the HEI's are not good above 6000 rpm. Is that true. my cam only pulls to 6200 so I don't go that high. Is it possible to upgrade the HEI or do I have to go with a different distributor? Quote Link to comment Share on other sites More sharing options...
grumpyvette Posted December 21, 2008 Share Posted December 21, 2008 yes its VERY easy to upgrade the distributor, one of the very first mods I did to my car was replacing the darn HEI, the low rpm multi spark helps the idle, the new distrib and ignition and wires pulls easily to 7K rpm with this.. http://www.holley.com/HiOctn/ProdLine/AV/IS/ISD/890-160.html MSD Ignition El Paso, TX 915/855-7123 http://www.msdignition.com the MSD 6AL ignition is just fine for most street/strip application when matched with the correct components http://www.msdignition.com/Products/Ignitions/Street/Strip/Analog/6420_-_MSD-6AL_Ignition_Control_with_Rev_Control.aspx http://store.summitracing.com/partdetail.asp?autofilter=1&part=TAY%2D79226&N=700+115&autoview=sku Quote Link to comment Share on other sites More sharing options...
saxfiend1967 Posted December 21, 2008 Share Posted December 21, 2008 I concur with grumpy .you should listen to him !! I used msd 6al and pro billet Quote Link to comment Share on other sites More sharing options...
Drax240z Posted December 21, 2008 Share Posted December 21, 2008 As much as I respect Grumpy's opinion, I must mention that the MSD ignition boxes I had seen for the past 2-3 years really seemed to be problematic. I have a 6A I use on my own car and have never had issues with it, but I believe the number was 4 MSD boxes with failures diagnosed during dyno sessions at my shop. I don't know about the quality of any of their other products, but I am personally quite wary of their ignition boxes. You mileage may vary... Quote Link to comment Share on other sites More sharing options...
grumpyvette Posted December 21, 2008 Share Posted December 21, 2008 CRANE makes a BETTER ignition, in my opinion, but my MSD works fine so its not getting replaced untill or if it fails... Ive seen a few MSD boxes that were burnt up internally but they generally are easy to test and either work or are fried. MSD 6 series ignitions are cheaper and more common, but theres far more durrable units available, from MSD,CRANE and other sources. http://store.summitracing.com/partdetail.asp?autofilter=1&part=CRN%2D6000%2D6400&N=700+115&autoview=sku Quote Link to comment Share on other sites More sharing options...
DavyZ Posted December 21, 2008 Share Posted December 21, 2008 I have an MSD 6AL on the 240Z engine and it worked fine, so I'm OK with their products for the most part. I'm going to use the 6AL on the V8 as well. That said, I took the stock HEI from the V8 and upgraded the heck out of it. Shortly thereafter, a friend gave me a free new Mallory Highfire billet disty, which I'll probably end up using because I know the sucker is new inside and out. Davy Quote Link to comment Share on other sites More sharing options...
josh817 Posted December 22, 2008 Share Posted December 22, 2008 I am having the same problem. Once I hit 5500RPM it feels like the power drops off. The cam I have is suppose to go from 3500-7500 (290-F or something like that from Schneider). However there are several things... 1: It could just be feeling the torque drop off since thats a typical spot 2: I don't have my wideband installed yet so maybe something there 3: I have a Borg Warner HEI module, however it looks and is labeled exactly the same as the GM kind so I'm not sure if the issues are the same. I read up that the GM one, meant for V8's, loses power in the higher RPM's or something like that due to the coil falling behind with demand. With that said, if its the coil that falls behind, does a Fireball coil or any of those hotter spark coils fix the problem? They're cheap so I bet its worth messing around with. I'm seeing how expensive those Holley dizzy's are in my catalog, add MSD or Crane to it and you have a lot of money in ignition! With that sort of money, are there any ECU's that do strictly ignition. I looked into SDS but they have fuel injection too. It would be really cool to lose the dizzy and use a trigger wheel or something. Then again... I don't know how I would get the front pulley bolt off with the motor in the car... Quote Link to comment Share on other sites More sharing options...
grumpyvette Posted December 22, 2008 Share Posted December 22, 2008 I am having the same problem. Once I hit 5500RPM it feels like the power drops off. The cam I have is suppose to go from 3500-7500 (290-F or something like that from Schneider). However there are several things... 1: It could just be feeling the torque drop off since thats a typical spot 2: I don't have my wideband installed yet so maybe something there 3: I have a Borg Warner HEI module, however it looks and is labeled exactly the same as the GM kind so I'm not sure if the issues are the same. I read up that the GM one, meant for V8's, loses power in the higher RPM's or something like that due to the coil falling behind with demand. With that said, if its the coil that falls behind, does a Fireball coil or any of those hotter spark coils fix the problem? They're cheap so I bet its worth messing around with. I'm seeing how expensive those Holley dizzy's are in my catalog, add MSD or Crane to it and you have a lot of money in ignition! With that sort of money, are there any ECU's that do strictly ignition. I looked into SDS but they have fuel injection too. It would be really cool to lose the dizzy and use a trigger wheel or something. Then again... I don't know how I would get the front pulley bolt off with the motor in the car... Ok, first the price issue, look around and shop carefully. you can find the holley distrib for less than 60% of list., and Ive posted links below on how to upgrade the HEI if you want to go that route. next point If your heads ,intake and exhaust scavaging won,t flow enough airflow to support 6000-7000rpm the cam used can,t possiable supply the flow rates either. next, learn to read plugs, its a skill youll need, to know, and with practice its almost as effective for getting a good idea to the a/f ratio and cylinder temps as an a/f ratio meter. Set your plug gaps at .045 and check your battery voltage and connections, and engine grounds, test your coil, and verify the ohms resistance on your plug wires, in no case shoud they exceed over about 300 ohms per foot, good wire reads less than 200 ohms, verify your timing curve and adjust your valves, carefully, verify your fuel pressure is a minimum of 4.5 psi at the carb, and the floats are set correctly. http://forum.grumpysperformance.com/viewtopic.php?f=70&t=202 http://forum.grumpysperformance.com/viewtopic.php?f=70&t=232 , yes a decent high output coil will help. Quote Link to comment Share on other sites More sharing options...
josh817 Posted December 22, 2008 Share Posted December 22, 2008 Yah the only readings I get from the plugs are at idle since I never have done a clean shut down. I'll probably have a dyno day sometime an January and then we can see if the torque drops off at that point. I'm still new so I can't feel the difference between torque and horsepower. The head is ported and polished, matched intake manifold, 6-1 headers however I'd like 6-2-1, with 40mm triple Webers which is probably a constraint there at higher RPM's. I really need to check what the venturi sizes are in them. Thanks for the reading material! Now lets hope any ignition upgrades won't fry the module... Quote Link to comment Share on other sites More sharing options...
pparaska Posted December 29, 2008 Share Posted December 29, 2008 Valvesprings given way? Maybe check the closed and open forces they exert. Quote Link to comment Share on other sites More sharing options...
GRUMPZ Posted December 30, 2008 Share Posted December 30, 2008 Accel and MSD make HEI upgrades that will easily handle 7000rpms at a fraction of the cast for a new system .around $100 and 30 min install.I used accel and had no issues and it allowed me to buy better valve springs with the savings. Quote Link to comment Share on other sites More sharing options...
josh817 Posted December 30, 2008 Share Posted December 30, 2008 .495/290º cam setup in my car so the springs should be hot ones. I'm just switching over to the EDIS setup since its so cheap. I guess my advice now would be to do the Accel HEI module and get a hot coil since its cheap, then do Crane or MSD. OR just avoid the module and get the E12-80 dizzy because the module is for the dummy dizzies which need an ECU to tell them when to fire and if you don't have the ECU like myself then you need the module. For anyone who wants my old ignition setup just PM me. It would be coil, module, and dizzy. Of course thats after I'm done with the EDIS conversion. Quote Link to comment Share on other sites More sharing options...
madden87 Posted February 4, 2009 Author Share Posted February 4, 2009 I went the cheap way and purchased the accel module and brute thunder coil. I think I paid about $100 for both. I ran a 12.5 before it started popping, a 12.8 20 minutes later, and a 12.3 after replacing the parts mentioned above. I think it was well worth $100. Since then I went from a 2400 stall that seemed worse than stock to a 3500. I will be at the track again this friday to see if I can hit a 12 flat. My previous times were with a 1.94 60' at best. Quote Link to comment Share on other sites More sharing options...
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