Tuned Port ??
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From: GA, USA
Tuned Port ?? Am trying to diagnos a problem on a tune port in a street rod.
86/305, using a speed density ECM.
Problem is: When I attempt to set base timing at 6*, I disconnect the ESC bypass, and look for the 6*... The first time I did this, it was waaay higher. Adjusted the dist to get the 6, and the engine won't start. I checked the rotor position.. dead on.
Adding timing w/ the dist will allow it to start, but run poorly. I added timng, shut it down, reconnected the ESC connector, disconnected the ECM power, then restarted the engine.. Way too much at idle.. 36*. Disconnected the ESC bypass... still 36*. The exh fumes are terrible, indicating a problem.
Someone mentioned that the dist module taking a crap will do this. Y? N?...
NE input is appreciated!
86/305, using a speed density ECM.
Problem is: When I attempt to set base timing at 6*, I disconnect the ESC bypass, and look for the 6*... The first time I did this, it was waaay higher. Adjusted the dist to get the 6, and the engine won't start. I checked the rotor position.. dead on.
Adding timing w/ the dist will allow it to start, but run poorly. I added timng, shut it down, reconnected the ESC connector, disconnected the ECM power, then restarted the engine.. Way too much at idle.. 36*. Disconnected the ESC bypass... still 36*. The exh fumes are terrible, indicating a problem.
Someone mentioned that the dist module taking a crap will do this. Y? N?...
NE input is appreciated!
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From: Omaha, NE
Never seen a module cause it, could be that the outer ring of the harmonic balancer has drifted causing your timing mark to be in error. A TDC check with a piston stop on cyl #1 may be in order.
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From: GA, USA
Yep...
Originally Posted by dynocar
Never seen a module cause it, could be that the outer ring of the harmonic balancer has drifted causing your timing mark to be in error. A TDC check with a piston stop on cyl #1 may be in order.
The customer had replaced the original balancer, as it had shucked the outer ring off location.
I wondered if the correct replacement was used. He said they checked the pt # several times, to be sure...
I'd guess it's not.
The piston stop is the next "stop".
Thanks, again!
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From: San Diego
Originally Posted by dynocar
Never seen a module cause it, could be that the outer ring of the harmonic balancer has drifted causing your timing mark to be in error. A TDC check with a piston stop on cyl #1 may be in order.
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I built..
Originally Posted by GOaT Cheese
Also the 5.0 and 5.7 had their respective timing indicators at different locations on the front cover. If a 5.0 balancer is installed with a 5.7 timing indicator...well you get the picture.
I'm confident that the cover is correct. And, as you mention, the balancer is likely a 350 item.
[The customer thot he was dealing above the intelligence level of Autozone, when he went to a parts store that knows better. NOT!]
I'll do the stop deal, and remark the balancer... All should be good to go, then.
Thanks for the help
Originally Posted by GOaT Cheese
Also the 5.0 and 5.7 had their respective timing indicators at different locations on the front cover. If a 5.0 balncer is installed with a 5.7 timing indicator...well you get the picture.
i used to have an 86 TA with the TPI. the balancer for the 305 carb is different than for the 305 TPI. the carb version had the timing mark on the balancer at 12:00. the TPI motor put it around 2:00. reason being is the TB hung over the water pump blocking the view of the mark from behind the water pump.
so, most likely he got one for the 305 carb motor and not the 305 TPI motor. the 305 TPI balancer is the same as one for a 350.
Originally Posted by Old Geezer
this engine 10 yrs ago, using all the original components, such as the ft cover, pan, yadda, yadda.
I'm confident that the cover is correct. And, as you mention, the balancer is likely a 350 item.
[The customer thot he was dealing above the intelligence level of Autozone, when he went to a parts store that knows better. NOT!]
I'll do the stop deal, and remark the balancer... All should be good to go, then.
Thanks for the help
I'm confident that the cover is correct. And, as you mention, the balancer is likely a 350 item.
[The customer thot he was dealing above the intelligence level of Autozone, when he went to a parts store that knows better. NOT!]
I'll do the stop deal, and remark the balancer... All should be good to go, then.
Thanks for the help
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Verdad Gallardo TECH Enthusiast
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From: San Diego
Originally Posted by mrr23
i used to have an 86 TA with the TPI. the balancer for the 305 carb is different than for the 305 TPI. the carb version had the timing mark on the balancer at 12:00. the TPI motor put it around 2:00. reason being is the TB hung over the water pump blocking the view of the mark from behind the water pump.
so, most likely he got one for the 305 carb motor and not the 305 TPI motor. the 305 TPI balancer is the same as one for a 350.
so, most likely he got one for the 305 carb motor and not the 305 TPI motor. the 305 TPI balancer is the same as one for a 350.
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Thanks for the... responses. 
The positive stop diagnosis is the next operation. I'll just remark the current balancer, and call it good. This "thing" is so much "fun" to work on, too. NOT!
The positive stop diagnosis is the next operation. I'll just remark the current balancer, and call it good. This "thing" is so much "fun" to work on, too. NOT!
