I am using a GM HEI distributor on my 350. I cant get it to clear the intake manifold. I am running a Poston S Divider. I could probably grind the manifold for clearance, but I'm not sure I really want to do that. What have the rest of you done? Heres a pic
I dont see anything wrong with a little notching for clearance,i cut some of the cap away on mine,just try and make the notch look good.
I run a Poston and my HEI clears with no notching. If your interference is because one of the four HEI cap hold downs hit, then it becomes all about distributor placement.
Change to the original distrib style and if you still want a CDI based system use a 6AL. If you need a rev. limiter you would need to do that anyway.
Dan The body of the distributor hits the intake without the cap on it. The cap would need even more clearance Please explain this to me. Is the 6AL a kit to convert my old point distributor similar to the Pertronics? I dont need a rev limiter since its basically a stock motor Thanks for the replies guys. I knew there were many that knew more than I. Unless the 6AL pans out, then it looks like I am grinding. One other question for y'all to ponder. If I grind the manifold and use the full bodied HEI is there a good module upgrade?
Take a look at this: www.davessmallbodyheis.com This is the way to go. Dave will completely rebuild your stock points distributor, recurve it correctly, and fit it with an MSD magnetic pickup, all for about 135.00. You can then simply plug it into an MSD 6AL box, and have a killer ignition system. Or he can convert it over to an HEI, by mounting the module to the bottom of the distributor. The MSD 6AL is probably the most common ignition box on street machines today. It is a capacitative discharge (CD) type ignition. The box steps up the 12 volts to about 450 volts, and applies it to the coil at the right time. The result is multiple sparks for each cylinder firing, with more spark energy to jump bigger gaps for better performance. It should be the last ignition system you have to buy. It can be fired with points or a magnetic trigger distributor. And yes you do need a rev limiter, everyone does. If you have your foot on the floor one day, and your trans doesn't shift for some reason, or you break a universal joint, the rev limiter can save your engine. This is a picture of Dave's magnetic trigger conversion.
Specman, Check out my pic above for the module upgrade. The grinding was very easy with my disc grinder and very hard to see with the cap on. If it wasn't so hard to see I would have cleaned it up more. I did it because when the dist was installed where I thought it should be the cap hold downs were constantly hitting the intake and preventing me from getting the timing where I wanted it. I pulled the dist in and out trying to get it in just the right spot but it still hit. It's not a stock intake or ignition anyway so I sure didn't mind grinding it. I still have the original intake and points dist if I ever want it to look stock. Larry, Is there dyno evidence, I can look at, to support the claim of increased HP by installing an MSD 6AL ignition?
Andy, I've never done a back to back test, but I'm sure someone has. I hope you don't think I sound like an MSD commercial :laugh: I'm just really pleased at how my Distributor and Digital 6 perform. No cylinder firing is exactly the same every time. Sometimes the mixture is a little harder to light. At higher RPMs, the engine can actually misfire, just once maybe, and you wouldn't even feel it. One firing may not produce as much power as the next, or the one after that. The MSD boxes produce multiple sparks for each cylinder firing, over 20* of crank rotation. That makes for a better chance of lighting the mixture everytime. That has to show up on a dyno pull, or time slip. The multiple sparks make for less plug fouling, and a cleaner idle. I've used an HEI in the past, and it is a good distributor. My last HEI even used the same module upgrade. Look at what most guys use at the track, not just our Buicks. It's MSD, and the faster they go, the more spark energy they need (not just voltage, amperage)
Larry, I used to race a NASCAR late model stock car and we ran the MSD box. In fact it was mandated. I still have one and I'd put it on the Buick if I saw evidence of a significant power gain. That's why I asked. I do understand and agree with the theory. One thing I learned with the race car about the MSD is that power will drop off significantly when the battery gets low. Thats not something you'd have a problem with in a street car. We ran 100 lap races and a lot of guys didn't run alternators. I ran one but used to only turn it on during the cautions. After I saw the power loss I ran the alternator for the whole race or at least the second half. ... but back to the question. Does anyone know where I can find the evidence? Has JW or JB or anyone with a dyno checked it out?
I really don't know Andy. You'd have to ask JB, or JW. The main reason I did't opt for an HEI in my current car is the size of the cap. I like the stock look for the distributor so that I can run the GS aircleaner, and stock upper rad hose.
