Distributors
- Thread starter eeh1
- Start date
tubman
Well-known member
I think you are comparing apples to oranges. The last flathead was produced (in the U.S. at least) 56 years ago, so you are correct instating that the manufactures haven't been wrong for 40 years. Things change with the times. A typical flathead wants 22 to 24 degrees of total advance, while the typical OHV engine needs around 36 degrees. This makes a flathead less sensitive to changes in timing. Sure, you might get slightly better gas mileage with a vacuum advance (which can be very tricky to set up), but your statement "lose the Mallory" simply is not good advice.
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Ol' Ron
Well-known member
The problen here is, Progress. Todat we have means to teat the engines thru the engine management systems on new cars. This type of system when applied to the flathead, would accomplish the same think.
Richard Kunc back a few tears ago ran a series of test on a built flathead (276.l-100) and many carbs a d ignition systems . THis was done with a (Road rig), this recorded all the engine functions. Load, rpm,vacuum, and AF.On tape. for review . With this information adjustments could be made to improve the performance and econmy of a flathead.
Now ALL that information was posted on the barn, and mostly ignores bu most of the Know it Alls. Today we still have the doubters.
Most spend a great deal of money building these engines. Yet very little thought is given to tuning.
Fortunately I had a chance to drive the car, and was very impressed with it's performance.
Richard Kunc back a few tears ago ran a series of test on a built flathead (276.l-100) and many carbs a d ignition systems . THis was done with a (Road rig), this recorded all the engine functions. Load, rpm,vacuum, and AF.On tape. for review . With this information adjustments could be made to improve the performance and econmy of a flathead.
Now ALL that information was posted on the barn, and mostly ignores bu most of the Know it Alls. Today we still have the doubters.
Most spend a great deal of money building these engines. Yet very little thought is given to tuning.
Fortunately I had a chance to drive the car, and was very impressed with it's performance.
tubman
Well-known member
What Ron is saying is very true. That's why I spent the better part of 3 days to determine that the point gap settings specified by Mallory were incorrect (at least for the distributor in my car). Had I just gone ahead and run with the gap set at the "official" .022", I too, would be advising folks to "lose the Mallory".
Gene1949
Well-known member
agreed Tubman
(22-24 degrees) at wide open throttle AND 1900-2200 rpms seems to be optimum.
BUT most of us never run those motors at wide open throttle AND tootle around town at 1200-1500 rpm or run down the road @ 70 mph (2600 rpms) and part throttle.
Don't know about setting the Mallory @ 22 thou. Maybe the OP was trying to set single points like that when any point distributor/coil needs" 32-34 degrees dwell. Setting single points that wide does all kinds of negative things as far as timing and spark quality especially running 6 volts.
I use feeler gauges for other things instead of setting points. Most point sets even back in the "good old days" needed to have the contact arm "tweaked" to optimize the contacts when beginning the dwell cycle.
(22-24 degrees) at wide open throttle AND 1900-2200 rpms seems to be optimum.
BUT most of us never run those motors at wide open throttle AND tootle around town at 1200-1500 rpm or run down the road @ 70 mph (2600 rpms) and part throttle.
Don't know about setting the Mallory @ 22 thou. Maybe the OP was trying to set single points like that when any point distributor/coil needs" 32-34 degrees dwell. Setting single points that wide does all kinds of negative things as far as timing and spark quality especially running 6 volts.
I use feeler gauges for other things instead of setting points. Most point sets even back in the "good old days" needed to have the contact arm "tweaked" to optimize the contacts when beginning the dwell cycle.
tubman
Well-known member
Agreed. One of the reasons I replaced the points in my Mallory was because one set was so severely mis-aligned that I could not bend them enough to get them even close. Had I not purchased that dwell/tach meter, I'd still probably be chasing my tail setting the point gap with a feeler gauge.
Ol' Ron
Well-known member
The only reason I wouldn't run aan old Mallory distributor is: It's old tech, designed back in the 50's when the industry didn't have the knowledge we have today. One reason why Richard's "Road rig" was so important. Now tuning a "STREET" engine, is abit different than a performance engine. Timing and carbonation have to work together. Just like today's engine management systems. After many carbs and ignition curves we found that the following system worked best on his engine. Now this is a "street driver. "
Mechanical advance 16* all in by 2000
Vacuum adv 8*
initial 2/4 not important now.
The only carb that worked well with this system was the Edelbrock 500 cfm. Others were tried but their tuning was more difficult. Jet changes in the Holley 390 and the 4GC were time consuming, However with a little effort could probably work just as well. I wanted to use dual to tipple carb intakes, but Richard thought that their only advantage was aesthetics. Actually we never considered them.
With an AF meter, he began the tuning process. It was during this process he realized he didn't have all the information he needed to make a "Logical" change. And thus the invention of the "Road Rig" He set up a 50 mile route that was 60% street and 30% hiway. Over a few months of trial and erroe . he established the following results.
20* at WOT
28* at cruise
This gave excellent acceleration and no detonation, with 91 Oct fuel and 20/22 MPG. I wouldn't get as good a mileage, because I was in the throttle most of the time
Thes numbers might nor suit rou engine but they are close and a good place to start. Changing rods in the carba\s mia a 5 min job.
Richard sold the car, baught a Camaro, and went back to Han radio
Mechanical advance 16* all in by 2000
Vacuum adv 8*
initial 2/4 not important now.
The only carb that worked well with this system was the Edelbrock 500 cfm. Others were tried but their tuning was more difficult. Jet changes in the Holley 390 and the 4GC were time consuming, However with a little effort could probably work just as well. I wanted to use dual to tipple carb intakes, but Richard thought that their only advantage was aesthetics. Actually we never considered them.
With an AF meter, he began the tuning process. It was during this process he realized he didn't have all the information he needed to make a "Logical" change. And thus the invention of the "Road Rig" He set up a 50 mile route that was 60% street and 30% hiway. Over a few months of trial and erroe . he established the following results.
20* at WOT
28* at cruise
This gave excellent acceleration and no detonation, with 91 Oct fuel and 20/22 MPG. I wouldn't get as good a mileage, because I was in the throttle most of the time
Thes numbers might nor suit rou engine but they are close and a good place to start. Changing rods in the carba\s mia a 5 min job.
Richard sold the car, baught a Camaro, and went back to Han radio
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Gene1949
Well-known member
Tankx Ron. Your numbers are pretty much where I'm at. Great setup for a driver with my 4GC. I'm still using the GM HEI brain and a newer "E"- coil. I did set the vacc can down to 13" though. I know you recommended 15". Opened the plug gap to .045. The drivability around town is amazing (Butt gauges/seat of the pants.).
tubman
Well-known member
Sounds like a real enthusiast. I'm not sure that this is someone we should try to emulate; sorry Ron.
C'mon, tubman! Sounds like Richard did a thorough job of testing and documenting, and was successful! What's not to emulate? Seems he saw a challenge, conquered it, and went on to new endeavors. Lots of people are like that.
There were pictures of the car on here, and Ol' Ron drove it, as I recall. seems there were a lot of posts about it.
tubman
Well-known member
I'm interested in what's happening now, what's working and what's not. I spent the better part of three days discovering that Mallory produced some documentation that may not be correct. Please try to understand what this thread is really about; some guy wants to know if a Mallory distributor is a good fit for his car. I have contemporary real world experience that has direct bearing on the O/P's original question. What someone said someone else did umpteen years ago is not really very useful.
Ol' Ron
Well-known member
I worked with Richard for several years, He had built several aircraft. A KR-1 that looked just like Spitfire with a VW engine. He wanted me to build an engine for him. However the shipping cost prevented him from sending it to me. Told him to find a machineshop that could do the work and i would help him assemble. Over the next several months he got it running and driving. He put a 94 carb on an adapter he mad for the 4bl intake. We sent many emails and phone calls, I hooked him up with JWL for the crank asy and Cam Techniques for the cam. I told him not to bother with the ports and valves, just a good valve job would do. I sent him a converted SBC distributor and he was off and running. Unfortunately the fuel mileage wasn't very good, so he took it on himself to find out why. The first thing he discarded was my distributor, reason no Vacuum advance, and the quest for better mileage was on. Sure I was Pi**ed, This no nothing tossed my dist. Fortunately I swallow my pride and went to work for him, and the rest is history. Sorry Tubman, I respect your knowledge here on the barn, but you might give him alittle slack.