This 250 CID L6 in my shop truck , has wobbly valve guides and burns quite a bit of oil , so much so it fouls the spark plugs often , making for poor idle and under load irregular missing . it needs a quart of oil every time I fill the gas tank . Last week I stumbled across a junked '76 Camaro with a 250 L6 , it has the early HEI with a separate ignition coil , I grabbed the whole thing , it was all encased in 1/4" of thick , dry grease & road munge , it took me until well past sunset Sunday to clean it all up , I left it drying in the garage until last night when I installed it and eyeballed the timing , turned the key and it roared into life , only 4° off on the timing to I re adjusted it and took it for a drive ~ wow what an improvement . I've said before that opening the spark plugs up to .035" minimum helps as does adding a Pertronix Ignitor system , this HEI is just wonderful ~ this morning @ 04:30 it lit right off and didn't stumble and miss as it often does , the power is greater and the engine runs *much* smoother now . I've not even cleaned nor re gapped the oil soaked spark plugs because I wanted to see if it would clean the plugs as I drove it on the freeway , it seems to have . these spark plugs are fairly new , maybe 2,000 miles on them . I'll open them up to .050" using a wire gauge next time I have them out . Interestingly , this HEI system works fine on the 7 volt points ignition feed , I'd expected to find it necessary to tap into the electric fuel pump's relay . I re used the old silicone 8 MM plug wires after a careful cleaning and application of Dielectric Grease to the connections on both ends .
I have an HEI on my 235, and it is quite an improvement. When I got mine, the recommended gap was .060, IIRC. A word of caution... I don't know what gauge wire you had originally running to the coil, but when I added the HEI to the '51 I was required to change the original wire from the switch to the coil to a 10 gauge wire. The explanation was that the HEI draws much more current than the original.
I spoke with Tom Langdon and asked about the 10 Guage wire. He said that it is not done for current draw but is actually to stop false trigger signals.
Well, I guess we all know what happens when one ass-u-me-s something... I just assumed the heavier wire was because of current draw.
Yep, GM made a real winner in their HEI. I use them on everything; Ford, Chrysler, even a Model A and this was long before Davis Industries was ever heard of. My 37 Buick straight 8 has one made from a Pontiac housing and a shortened V8 Chevy driveshaft. Ever since I've owned it the carb perculates after driving for a half hour or so and with points one had to grind on the starter for 20 or so turns before it fired off and cleared the cylinders with a big cloud of black smoke. Fuel regulator set at 2#'s, carb insulator block, fuel lines isolated from heat, float as low as possible, Viton tipped needle, nothing has cured the problem but with the HEI and a .045 gap it fires after just a few turns. Still blows the cloud but that's the guys behind me problem.
Poor Fuel Hot Starts Yeah as time goes by , the corn based Foo-Foo ' motor fuel ' ('cause it ISN'T GASOLINE !) just gets worse & worse . the winter blends evaporate in a few minutes of shutdown , I have this same hard starting problem ~ I really need to go in and open up those .035" spark plugs , maybe this weekend , I have oil filter and lube planned now then the leaky head pipe gasket again ... Maybe I can do the plug gaps too .
Pertronix for GMC So gurus of all things straight 6, I like all that I hear you guys saying about the HEI. To install a Pertronix system on my 228 do I use the GMC model or the Chevy model because I am converting to negative ground 12 volt system for the truck? Does it matter? TIA
Pertronix " Ignitor " Good question Jason ! . I'm no Guru but I do use and like the Pertronix Ignitors, they are NOT HEI , they just increase spark intensity by driving the stock ignition system to it's maximum output , thereby increasing power , and fuel economy and simultaniously improving starting hot or cold . You're wise to consider the grounding aspect as yes , it matters greatly . If you copy the 10 digit Delco-Remy part # off the side of your dizzy and E-Mail it to them , they'll tell you which model to buy , be sure to mention 6 or 12 volt and Positive or Negative grounding . Then just go to any Hot Rod shop and order it up from there to get the best price .
I am glad I read this thread. I was debating the pertronix. It sounds like a good Idea. I would like to get as much performance out of that long motor 228 as possable
Pertronix " Ignitor " Remember : READ the instructions and measure the coil's resistance , it MUST be the ohms Pertronic tells you to use or the Ignitor will prolly burn out in a year or two , making you pi$$ed off but your own fault . I'd highly suggest at least a NAPA Echlin Epoxy filled coil but I* have one vehicle running a bright yellow ACCEL coil and boy howdy does that thing ever throw sparks ! not too overly $pendy either , I just hate the bright yellow aspect on my old Motocycle.... Remember to : open the spark plugs up to at LEAST .040" gap ! go buy a new wire typ spark plug gauge , you'll need it . Since I opened the gaps up on my 250's plugs , the oil hasn't (yet) been able to foul the plugs again , it usually does so in a matter of days so we'll see but the smoothness and power affected by wider plug gaps has to be felt to be believed . I LOVE this rusty old base model truck ! .
Will one of these HEI distributors fit my 235? OK, I went back and looked at Fab51's post, and it appears that the HEI is available for the old 235, I guess I'd like to know where to get such a thing, and about what to expect to pay.
HEI For 216/236/261 Yes but , they have to machine the bottom end of it a bit , I see them on Flea-Bay for $150 or so , forget about the B.S. ' lifetime warranty ' as they'll be gone in a year . I see these for sale in most Auto Swap Meets too . Maybe simpler is the excellent Pertronix " Ignitor " that replaces your current dizzy's breaker points and drives the stock system to it's full output . You MUST follow the instructions including testing the coil's impedance exactly or it'll burn out , that's why you hear a fair amount of critical comments against Pertronix , lazy bubbas don't read nor follow instructions then complain when it of course fails..... I've been running one for many years & miles in an oldie , never any troubles atall . Looks better under the hood too as Pertronix retains the original dizzy . This old C/10 needed serious help due to massive oil fouling so I went directly to my favorite parts place : Pick-A-Part & chose the " Just So " unit I wanted then I had to spend hours cleaning off the black taffy like gooey crud before I could install it.... So far it's terrific . Your pays your monies and makes your choice . BTW : yes , I'm a lazy , uneducated Bubba Farm Boy too , that's why I follow directions ~ I'm FAR too lazy to do things twice .
Hey, thanks again Nate. You always give a good answer. I'd been looking at the Pertronics, and then saw the HEI comments and wanted to explore both. I was pretty sure I'm gonna' go with the Pertronics, as I've read a lot of good stuff about them, including your info about matching the coil, and polarity. I'm a retired electrician, so that stuff makes sense to me as well. I've got a ways to go before I'm close to runnin' the engine again, so I'll wait to order the ignition upgrade so as not to waste any warranty time, if I can. Haven't worked on the truck but once since I got her here in mid January, as I've promised my Wife I'd build a fence first... musn't renig on a promise.
Go pertronix and use their coil. It is black and if you face the label toward the engine, no one knows it isn't stock. This is what I used on the 53.
Confession I bought the Pertronix coil and electronic ignition, but fried it out of the box. Not because I didn't read the instructions, but if'n I remember correctly, the wiring to my starter and coil was not the way it was pictured and described. I thought I installed it per the Pertronix instructions and got no spark/start. Then tried it the way I was previously wired and up in smoke went the ignitor. It wasn't very pretty watching that $100 dollar bill go up in smoke. IIRC there was a little confusion between what the coil wiring instructions said and the ignitor wiring said as well. I'm still using the coil, but the ignitor is toast. Russ - Did you happen to take any photos of the way you had the '53 wired up?
Bummer , That @ lunchtime I went out to my '69 C/10 , pressed the gas once and turned the key in the cold damp air (it's raining in L.A. again) and it cranked , belched a large cloud of blue & black smoke & fired right up , didn't miss a beat .
I'm extremely happy with my HEI also. I started the '51 to warm up before I left for work this morning. When it was time to leave, I noticed that there was not even one little dribble of black in the snow under the tail pipes. Perfectly clean. That made me quite happy.
If I remember correctly... The HEI from the old Iron Duke 153 may also be an option for the newer inlines - at least on the 250. just user a 6 cyl cap. I put one on My 71way back when it was alive... It was the best mod I did to that truck. Of course, since most of the vehicles with an Iron Duke were pretty much disposable, they are prolly harder to find than an inline 6 Bob
Don't think that would do the job, at least not without changing out the four pointed "star wheel" (my words, I don't know the real name) for a six point star wheel.
