Ok so some of you have seen my build. I have a 37 ford flathead v8 with a mcculouch supercharger on top and two strombergs stuffed in a model a.ni rebuilt the carbs, new plugs , good coil, good condenser.... It runs like a champ cold. When it gets warm, look out. It backfires and pops, no power , smokes. .... I installed a vacuum block and a line for the brake in the distributor. That helped alot. But it seems like the timing it's just way to retarted or something. But it's adjusted all the way advance and still seems retarted..... What the heck do I do. Posted using the Full Custom H.A.M.B. App!
Please explain the above..! What exactly is the timing set to ? What does all the way advance mean ? I've seen others not advance their supercharged engines timing enough and they have all kinds of problems. Why it takes "someone else" to do the timing...I also don't know. Check for vacuum/pressure leaks, plug wires crossfiring...and what ignition timing values is the timing set to ? Mike
The vacuum brake needs some tension to stablize the spark timing but under boost the brake would retard the ignition timing. The helmet distributor is a good distributor but will need set up for the blown engine. A 40B distributor is a common unit and offers 16 degrees of mechanical timing, should make a nice unit for the blown engine. The mechanical advance would swing out at approx 2500 rpm and the vacuum brake would retard slightly when boost or positive pressure was achieved. None of this has anything to do with the temp etc. I would suspect a leaking condensor based on heat or coil break down etc. Be glad to check and set up the unit if needed...
Bubba, can you put some figures together and pm me. I really need this thing running correctly ASAP. I haven't found anyone that could give me a straight answer on how a dist should be set up . The blower is kinda an odd setup. I have a new coil and condenser ill put those both on and see if that changes anything. I have two cruise ins this weekend and hope I can straighten it out enough to drive it there, only a few miles today. I drove it to town today, right up with traffic at 55-60 mph. It was great! Then it started running terrible on the way back. And I know it's ignition based . Posted using the Full Custom H.A.M.B. App!
Also I have a negative pressure to the distributor .. I installed a carb adapter . Posted using the Full Custom H.A.M.B. App!
I think I fixed it... Bubba mentioned a leaky condenser... Fantastic guess!!! It was soaked. Also, after i changed that, I noticed between the few different distributors I have here, there were 3 different springs in them or the break. My original one looked like someone cut it down. So I stuck a new one in and adjusted the timing a wee bit and the thing just runs ...!!! Posted using the Full Custom H.A.M.B. App!
Thats what the hamb is good for. Many ideas and options on what to get done. Be glad to help , curious as to what the vacuum reading would be using the carb plate. I would think the brake would love vacuum from the other side of the intake etc. That way when boost was built up the brake would retard the timing and when boost was low the brake would be pulled away allowing normal operation. Let see a picture of the distributor on your car....
I agree with your thoughts. That's why I was puzzled when it wouldn't run right. And as soon as I put the vac plate on there it came to life. I haven't driven it down the road yet since i replaced the condenser , but a couple hole shots in the driveway, I sure could see the difference . Ill get a few detaield pictures tonight Posted using the Full Custom H.A.M.B. App!
Replaced coil and condenser, ran great cold. Runs like dog shit hot . Thought I had it fixed Posted using the Full Custom H.A.M.B. App!
Mine backfired and popped also lost power. I had spark plug crossfire and blown power valves in the carbs. Once I changed plug wires, cap and rotor , re built the carbs and fixed the power valves the problem was solved
I'd say get Bubba to set you one up, He set up a dizzy for me, I got a more than wicked distributor, waaaay more than I asked for or even imagined, it was a work of art, old brass condensor and all, and I even got a t shirt and a bottle of bubbas hot sauce! that alone was worth it, but the dizzy was bitchin too
I called him today. I was a little late he left for the day. I'm done Dickin with it, ill have him fix it Posted using the Full Custom H.A.M.B. App!
Ok lets try this one for a fix !!! Built a new helmet unit for this car and used the three bolt , three bolt coil housing for the early engine with a 11A advance unit in it . Ran distributor on tester and unit will advance 11 degrees ( thats 22 engine) at 2500 rpm. Adjusted the vacuum brake three turns out to apply slight load under low vacuum. Hooked up line to vacuum brake and applied slight pressure , the brake will retard under boost , should be perfect for a supercharged engine !!! 3 psi boost retards eight degrees... With some tuning you should be able to make this application perfect !!!
I was not able to make any progress on getting this car running good at all. Here's what I am running into.... I replaced the dizzy with one from bubbas. Bolted it on the car, it wouldn't barley even start. When it did, the timing was so retarted that it puffed black smoke and sounded like I was pulling a semi truck up a hill... Terrible . So I had no choice but to advance the timing a few degrees. So I did just that... Score! It ran great... Now the throttle was sluggish. Meaning that when I pulled out on the road it had no power as If it was taking forever for the timing to advance. When it finally did, it would take off like a Rocket, very impressive ... At an intersection you had to rev it pretty high to get it to move along, then once it was rolling you had to very gently ease into the throttle or it would just spit and pop and cough. But if you eased into it, it would lite and take off like a rocket. .... Now after about 15 mins of drive time it would warm up to 150-170 and then run like s Dog shit. So in my mind it was either a condenser or a coil ... So I replaced both. And backed the brake off just a hair.. It seemed great. 20 mins of drive time go by and it would just run like ass again... WTF! So back home we go. Popping and coughing, no power. So I got it home and installed the coil adapter kit on it. Remote located a brand new 6v coil with a brand new condenser on the dizzy, now it barley startes at all, no power at all, worse than before. Cannot even pull it out of the garage. So I put the helmet coil back on, bam! Starts good, runs good for a few mins then crap. Shut it off and let it cool, runs good again. I haw excellent fuel delivery, clean plugs, 90lbs compression across the board. Any ideas!? This mcculouch charger is about to find itself on a shelf....
I'm not a flathead guy or into blowers, but I'd be taking off the twin carbs and run one while sorting it out. Also, my impression listening to it when you nail it. It is idling too slow to stuff it with all 4 barrels open, and expect a snappy responce. The blower must be near inop at that low RPM? also seems way retarded to me. One carb, raise idle a lot, crank the timing and try it. Then color check plugs to see if it needs richer jets
One carb doesn't even wanna make this thing run. Not with out re jetting it severely. In the video I'm not really nailing it. It runs that way easing into it .. I will take your advice and and see what happens tomorrow
Seems like it was running OK July 4 from the BBQ vid. Back track everything you did since. It has to be there somewhere.
It still runs that good with the stock coil on it, until it gets up to full operation temp and then it's starts cutting out and what not.. The video at 4th is a cold start and cruise down the road. The video after that in the garage is with the aftermarket remote coil and at full op temp Posted using the Full Custom H.A.M.B. App!
Uptade: factory coil and condenser: 6v supply. Drove it to town today .. Ran and acted beautiful! Came all the way home, perfect. Let it sit and idle to test the overheating coil theory, backed it out the drive, bam! Runnin like ass.. So that's all it's gotta be.
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