Establishing your initial timing question
07-24-2014, 12:27 PM
#22
Initial
Sorry, my public school math has failed me again, that should read 20*. That is just an example. Yes 900 to 1000 rpm is my idle. Oh and my combination is not stock so 9" hg vacuum is not too bad. Need to keep it steady however or the power valves will flutter and the car will idle very rich. I guess my question is, is there a rule of thumb for establishing you initial advance?
07-24-2014, 12:34 PM
#23
950
Now that is interesting. I have PVs in both my primary and secondary bowls. Been chasing tune for a couple of years now, the best investment i ever made was a LM-1000 wide band O2 analyzer. When I dyno my car, I log my own O2, RPM and vacuum on my lap top in the car and watch it real time. Its time to get a correct carb for the car. I have been running a 830 CFM marine carb for years. Looking to go to a 950 Holley.
07-24-2014, 01:10 PM
#24
Melting Slicks
Thread Starter
I looked at it and downloaded the installation PDF. Looks interesting, the example they give, I couldn't figure out how to make the numbers add up using the tables they provide. Also seems to limit distributor advance selection to 4 total advances, 10, 15, 20 and 25 degrees. They could have added a little more detail and maybe a couple more examples. I wonder if one can set the dials to anywhere between the numbers for infinite selections between 0-25* for the "Electronic Centrifugal Advance"?
Last edited by KJL; 07-24-2014 at 01:14 PM.
07-24-2014, 01:20 PM
#25
Had a 1976 L-82, 4-sp
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Royal Canadian Navy
I looked at it and downloaded the installation PDF. Looks interesting, the example they give, I couldn't figure out how to make the numbers add up using the tables they provide. Also seems to limit distributor advance selection to 4 total advances, 10, 15, 20 and 25 degrees. They could have added a little more detail and maybe a couple more examples. I wonder if one can set the dials to anywhere between the numbers for infinite selections between 0-25* for the "Electronic Centrifugal Advance"?
07-24-2014, 02:09 PM
#26
Safety Car
07-24-2014, 03:18 PM
#27
Melting Slicks
Thread Starter
Hmmmm....interesting. I see four families of advance curves not counting lock out or vacuum. 1 each for each of the four advances I list above. For each one of the 4 total advances there are 4 different rpm values the advance will all be in by. That is 12 different possibilities but still only 4 mechanical advances to chose from. I cant make the numbers add up in their example so I obviously am missing something.
07-24-2014, 04:32 PM
#28
Team Owner
The E-curve is a POS. 100 possible choices and maybe 6 are usable. It was not made well and they have not fixed it to my knowledge.
Example on mine the steps are 5 degree increments. They need to be finer like 2 degree in the common range. Not 0 -50 degree mechanical advance in 5 degree changes. It is the same with the vacuum advance.........
Example on mine the steps are 5 degree increments. They need to be finer like 2 degree in the common range. Not 0 -50 degree mechanical advance in 5 degree changes. It is the same with the vacuum advance.........
07-24-2014, 06:19 PM
#29
Melting Slicks
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St. Jude Donor '05-'06,'11,'13-'14,'16,'18,'19
The E-curve is a POS. 100 possible choices and maybe 6 are usable. It was not made well and they have not fixed it to my knowledge.
Example on mine the steps are 5 degree increments. They need to be finer like 2 degree in the common range. Not 0 -50 degree mechanical advance in 5 degree changes. It is the same with the vacuum advance.........
Example on mine the steps are 5 degree increments. They need to be finer like 2 degree in the common range. Not 0 -50 degree mechanical advance in 5 degree changes. It is the same with the vacuum advance.........
There is a limit to what it can do but for the price its not a bad deal. The next step in adjust ability is the programmable box with good software but I really don't see where the street driven car with a mild SB or BB needs the adjustable box.
The E-Curve is a great dissy for what it is, it includes a rev limiter, 3 wire hookup and a multitude of advance curves to tryout simply by removing the cap and turning a couple dials. If you are running a separate ignition box, you don't have to with the e-curve.
An added feature of running the E-curve is if the ignition box fails you can bypass the box and the car will run with just the dissy.
The instructions for the E-curve are lacking, you need to set the the dissy at the total advance you want including vacuum then work backwards. If you want your total to be 36* without vacuum then set the dissy at 36* and decide what initial you want, say you want 16* initial so you would use the 20* chart. The dissy will take out 20* at start up and add it back in based on the curve you select.
Neal
07-24-2014, 07:34 PM
#30
Team Owner
Thats your opinion and I'm OK with it, but do explain. If you don't like it due to what you call only 6 possible usable curve choices then it just does not fit your needs. Sounds like you need an adjustable ignition box that is PC programmable. Trust me if MSD felt that it only needed 6 possible curves to address every possible scenario then that is all it would have.
There is a limit to what it can do but for the price its not a bad deal. The next step in adjust ability is the programmable box with good software but I really don't see where the street driven car with a mild SB or BB needs the adjustable box.
The E-Curve is a great dissy for what it is, it includes a rev limiter, 3 wire hookup and a multitude of advance curves to tryout simply by removing the cap and turning a couple dials. If you are running a separate ignition box, you don't have to with the e-curve.
An added feature of running the E-curve is if the ignition box fails you can bypass the box and the car will run with just the dissy.
The instructions for the E-curve are lacking, you need to set the the dissy at the total advance you want including vacuum then work backwards. If you want your total to be 36* without vacuum then set the dissy at 36* and decide what initial you want, say you want 16* initial so you would use the 20* chart. The dissy will take out 20* at start up and add it back in based on the curve you select.
Neal
There is a limit to what it can do but for the price its not a bad deal. The next step in adjust ability is the programmable box with good software but I really don't see where the street driven car with a mild SB or BB needs the adjustable box.
The E-Curve is a great dissy for what it is, it includes a rev limiter, 3 wire hookup and a multitude of advance curves to tryout simply by removing the cap and turning a couple dials. If you are running a separate ignition box, you don't have to with the e-curve.
An added feature of running the E-curve is if the ignition box fails you can bypass the box and the car will run with just the dissy.
The instructions for the E-curve are lacking, you need to set the the dissy at the total advance you want including vacuum then work backwards. If you want your total to be 36* without vacuum then set the dissy at 36* and decide what initial you want, say you want 16* initial so you would use the 20* chart. The dissy will take out 20* at start up and add it back in based on the curve you select.
Neal
07-24-2014, 09:41 PM
#31
Burning Brakes
I had nothing but problems with Power valves running a 6-71 blower on a stroked 350. Sold the standard Holley's and bought 2 external controlled power valves 600 duel feed d-pumper Holley's carbs drilled a line in at the manifold pop off valves to get the vacuum to control them. Works great!
07-25-2014, 01:21 AM
#32
Team Owner
I had a discussion with the forum expert "Lars" over the weekend and we agree on timing settings.
Do you have high VE, modern fast burn heads, good A/F ratio, indexed or multi tip plugs? Or possibly even a car with OD driven at lower rpm creating higher cylinder pressures
Yes, to the above questions would require 3000 3200 all in
Do you have high VE, modern fast burn heads, good A/F ratio, indexed or multi tip plugs? Or possibly even a car with OD driven at lower rpm creating higher cylinder pressures
Yes, to the above questions would require 3000 3200 all in
Even if you don't have noticeable ping/knock. I've rebuild a few hot rod motors that had all the coating gone down to the copper. Those motors were working against them selves even with higher octane
07-25-2014, 01:31 AM
#33
Safety Car
I had nothing but problems with Power valves running a 6-71 blower on a stroked 350. Sold the standard Holley's and bought 2 external controlled power valves 600 duel feed d-pumper Holley's carbs drilled a line in at the manifold pop off valves to get the vacuum to control them. Works great!
07-25-2014, 03:08 AM
#34
Melting Slicks
I like the idea of a programmable distributor provided it doesn't require 10 miles of wire harnesses, who makes them? Also, my statement requiring 85+ was based on plugging the primary PV for experimentation. I am currently running a 78 for my primaries.
What made you select 18* as you initial value? I did exactly what you have done but I came up with 21 initial and 15 mechanical. I based my decision on idle quality and A/F ratios. I experimented with several lower values but the idle was just to rough. Sounded like I had some sort of mega race cam or something.
What made you select 18* as you initial value? I did exactly what you have done but I came up with 21 initial and 15 mechanical. I based my decision on idle quality and A/F ratios. I experimented with several lower values but the idle was just to rough. Sounded like I had some sort of mega race cam or something.
http://www.aldonamethyst.co.uk/
08-14-2014, 09:29 AM
#35
Melting Slicks
Thread Starter
Have a look at this system then, its not made in the good old USA but seems to fit your requirements -
http://www.aldonamethyst.co.uk/
http://www.aldonamethyst.co.uk/
08-14-2014, 01:32 PM
#36
Safety Car
08-14-2014, 02:53 PM
#37
Melting Slicks
Thread Starter
08-14-2014, 05:40 PM
#38
Safety Car
08-14-2014, 08:14 PM
#39
Melting Slicks
Thread Starter
Not many. Maybe 10,000 at the most. I built it about 8 years ago but knowledge and technology has grown regarding large displacement small blocks. I have the block and rotating assembly at engine shop for a complete evaluation. Looking to go from a 427 to a 434. Don't ask why,....just woke up one day with a hair across my a$$ to do it and pulled the engine. Going to be a high dollar build. Seeing what Paul had accomplished with his 427 build has inspired me to re-discover my hobby. Due to an unexpected layoff, I put my life on hold for the last 8 years to re-establish myself into a new career. I am ready to blow the dust off my tools and start having some fun again and thought this would be a great way to jump start it.
08-16-2014, 12:23 AM
#40
I'm running 24 degrees initial with the lightest springs all in by 2500. An adjustable mechanical would be nice other than bushings, I've been looking at the msd ecurve but I'm not for sure it would fit behind the blower I got in the garage if I ever end up going that route, programable curves with no box would be nice.
Last edited by cagotzmann; 08-16-2014 at 12:29 AM.