distributor
- Thread starter jwilson
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mygasser
Well-Known Member
no you don't and and yes you are correct 
that's not the answer i was looking for I'm having super trouble with the car 1974 dodge dart
I got the car timed 10 over TDC witch gave me about 22 degrees advance and car in shop sounded and ran great
first road test it went through first great then shifted to second then started to have a misfire and i cant figure it out
I got the car timed 10 over TDC witch gave me about 22 degrees advance and car in shop sounded and ran great
first road test it went through first great then shifted to second then started to have a misfire and i cant figure it out
Best advice can offer is to find someone close to you who can help. maybe Junkyardhero of moparofficial
I say that because you've posted that computer is difficult and its no easier on this end of the screen for us if we don't know the specifics.
Second best. I'll give this a shot.
Need to first determine if this is a tuning issue or a parts and assembly issue.
In other words, is this DUI distributor its hookup failing or have a poor connection, or not hooked up right?
Or is it not setup correctly for what you have?
I can't answer that with the limited information but at least those are the two possibilities.
If it ran good before the changes, then go back to that. That's your baseline.
One more thing that will help is knowing what you are working on.
'74 Dart
with a slant six (225 cid) or a small block v-8 (such as a 318)? If its a six then we'll want to move this to the correct forum to reduce confusion.
Then your wrote "tri-power". That usually means three 2-barrel carburetors, and is a Pontiac phrase. Chrysler called it a six-pack. Regardless. if this is on a '74 slant six or a v-8 it suggests some hot rodding under the hood. The tuning will be different than a stock engine.
I say that because you've posted that computer is difficult and its no easier on this end of the screen for us if we don't know the specifics.
Second best. I'll give this a shot.
Need to first determine if this is a tuning issue or a parts and assembly issue.
In other words, is this DUI distributor its hookup failing or have a poor connection, or not hooked up right?
Or is it not setup correctly for what you have?
I can't answer that with the limited information but at least those are the two possibilities.
If it ran good before the changes, then go back to that. That's your baseline.
One more thing that will help is knowing what you are working on.
'74 Dart
with a slant six (225 cid) or a small block v-8 (such as a 318)? If its a six then we'll want to move this to the correct forum to reduce confusion.
Then your wrote "tri-power". That usually means three 2-barrel carburetors, and is a Pontiac phrase. Chrysler called it a six-pack. Regardless. if this is on a '74 slant six or a v-8 it suggests some hot rodding under the hood. The tuning will be different than a stock engine.
This may help too.
TDC is when the #1 piston is at the very top of the compression stroke. Top Dead Center
Timing is the number of crankshaft degree either before or after TDC the spark will be fired.
Initial or base timing: Timing with no advance added.
Normally on a stock engine timing at idle is the baseline. Idle is usually 500 - 650 rpm (pre-smog), or 600 - 850 rpm smog era.
Hot rodded and race engines requires some trial and error tuning to get the idle speeds down anywhere close to 700 rpm.
When you are measuring timing at idle it is critical to note the rpm. On many distributors timing at 800 or 900 rpm will likely be base timing plus some mechanical advance. Don't worry about it, just be aware of it and always write down the rpm of the timing measurement.
Mechanical Advance: Degrees added by the distributor's weights moving outward with rpm. Sometimes called centrifical advance, often just called advance.
Total Timing: Initial timing plus the maximum mechanical advance. With hot rods and race engines, sometimes the idle timing is very unstable, especially early in the tuning process. For that reason, in those situations a high rpm timing measurement is a better reference. For example, Mopar Performance instructions suggest measuring at 2800 rpm. It is critical to know the RPM of every timing measurement.
Mechanical or Centrifical Advance
Compensates for the reduced amount of time (miliseconds) available for the burn as rpm increases. Because engine efficiency decreases burn time as rpms climb, the rate of advance slows down as rpms increase. A 'low performance' 318 usually has good lower rpm efficiency, but does not gain as much efficiency with increasing rpm. A 'high performance engine' is usually the opossite.
Vacuum Advance:
TDC is when the #1 piston is at the very top of the compression stroke. Top Dead Center
Timing is the number of crankshaft degree either before or after TDC the spark will be fired.
Initial or base timing: Timing with no advance added.
Normally on a stock engine timing at idle is the baseline. Idle is usually 500 - 650 rpm (pre-smog), or 600 - 850 rpm smog era.
Hot rodded and race engines requires some trial and error tuning to get the idle speeds down anywhere close to 700 rpm.
When you are measuring timing at idle it is critical to note the rpm. On many distributors timing at 800 or 900 rpm will likely be base timing plus some mechanical advance. Don't worry about it, just be aware of it and always write down the rpm of the timing measurement.
Mechanical Advance: Degrees added by the distributor's weights moving outward with rpm. Sometimes called centrifical advance, often just called advance.
Total Timing: Initial timing plus the maximum mechanical advance. With hot rods and race engines, sometimes the idle timing is very unstable, especially early in the tuning process. For that reason, in those situations a high rpm timing measurement is a better reference. For example, Mopar Performance instructions suggest measuring at 2800 rpm. It is critical to know the RPM of every timing measurement.
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Purpose of Spark Timing:Mechanical or Centrifical Advance
Compensates for the reduced amount of time (miliseconds) available for the burn as rpm increases. Because engine efficiency decreases burn time as rpms climb, the rate of advance slows down as rpms increase. A 'low performance' 318 usually has good lower rpm efficiency, but does not gain as much efficiency with increasing rpm. A 'high performance engine' is usually the opossite.
Vacuum Advance:
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Professor Fate
Push the button, Max...
Confusing, yes; but he did name it correctly. DUI's slant six distributor is called a "Tri Power" by the manufacturer and is just a model name, maybe a reference to its three-wire hookup or something, but not a reference to carburetion.
Dodge Slant 6 Tri-Power Distributor – Performance Distributors
It does sound like a timing issue, I'm just not sure what's meant by "10 over TDC"; it's normally referred to as before or after TDC and that could be an issue.
Is it backfiring out the exhaust or popping back through the carburetor? Or if it is a misfire, as you say, are all the plug wires correctly located in the distributor cap and fully seated?
Was the timing set with the vacuum advance disconnected and the line plugged?
Dodge Slant 6 Tri-Power Distributor – Performance Distributors
It does sound like a timing issue, I'm just not sure what's meant by "10 over TDC"; it's normally referred to as before or after TDC and that could be an issue.
Is it backfiring out the exhaust or popping back through the carburetor? Or if it is a misfire, as you say, are all the plug wires correctly located in the distributor cap and fully seated?
Was the timing set with the vacuum advance disconnected and the line plugged?
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