Moved this conversation over from bp on the advice of some of folks over there. I just received the dui unit last week and tore into the install this afternoon. See below.
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just spent a couple hours this afternoon trying to get my new dui system setup on a internally stock non-ic 392, edelbrock 1405, headers ect... The dui unit is purchased from IHOnly and is brand new w/ the livewire plug wires. I went ahead and did the 180 degree cap rotation trick by removing the plastic notch and rotating. It was easy enough to do and put the vacuum advance in such a place that I could spin the dist freely. Timed the engine off of #8 tdc and hooked up my timing light. Was able to get it to fire and dial it in around 12-15 btdc and it runs like a champ. My partner shuts the engine down and I snug up the hold down clamp. Turn the key... Engine spins but seems like no spark. I go ahead and doublecheck the 12v input, and spin the engine over looking for a spark in the timing light and plug itself. No spark.
At this point we walked away for 15 mins.... Came back to the truck and it fired right up. Timing still at about 12-15 btdc....no issues. We let the truck warm up fully to 180 or so and grabbed a beer in celebration truck ran fantasic, great throttle response, couldn't be happier. This being my first 392 the engine seemed waaay better than the 345 I recently put to bed. It burned off that new paint smell, no leaks to speak of. I was a happy guy.
We shut the truck down and proceeded to do some other tasks w/ the rollcage, seats ect... 15 minutes later we go to fire up the truck and nothing...... It spins and spins.... I pull the #8 plug to verify spark to the cylinders (been down this road before) and we are getting no spark. From this point we began to suspect something May be up w/ the dui unit itself. This engine has proven to be timed correctly, shutdown/restart several times and perform like an engine is suppose to.
No spark from any of the plug wires though... I was getting extremely frustrated at this point and decided to go a completely different direction. We pulled the entire dui unit out and put the dist/coil setup from my previous 345 into the 392. Timed off of #8 tdc, setup the timing light and dialed it in about 8 degrees btdc. This time the engine sounded completely different. We shutdown/restarted about 8-10 times attempting to prove we had no issues with spark. The engine sounded like it was missing and it didn't feel near as nice as when it ran well with the dui unit. But it always had spark and would fire immediately. I'm wondering at this point if there is a difference in running a dist/coil from a 345 on a 392??? We went ahead and reassemble the dui unit back on the engine and attempted to fire it up. No spark......
Per the instructions from dui and other threads on the board, I verified the input voltage to the dui unit to be 12.23. We used the same new optima battery for all the tests.
I really want to use the dui unit as it was a big investment, running perfectly, and was all that I expected it was going to be. It just seems like its acting erratically and not providing consistent spark.
I don't post out here much, I prefer to read, try, troubleshoot myself until I'm completely out of options. I'm hoping someone on the board can help me diagnose this issue. Its Saturday now and I'll be giving performance distibuters a call on Monday if I can't figure this out.
Thanks in advance guys!
##############
just spent a couple hours this afternoon trying to get my new dui system setup on a internally stock non-ic 392, edelbrock 1405, headers ect... The dui unit is purchased from IHOnly and is brand new w/ the livewire plug wires. I went ahead and did the 180 degree cap rotation trick by removing the plastic notch and rotating. It was easy enough to do and put the vacuum advance in such a place that I could spin the dist freely. Timed the engine off of #8 tdc and hooked up my timing light. Was able to get it to fire and dial it in around 12-15 btdc and it runs like a champ. My partner shuts the engine down and I snug up the hold down clamp. Turn the key... Engine spins but seems like no spark. I go ahead and doublecheck the 12v input, and spin the engine over looking for a spark in the timing light and plug itself. No spark.
At this point we walked away for 15 mins.... Came back to the truck and it fired right up. Timing still at about 12-15 btdc....no issues. We let the truck warm up fully to 180 or so and grabbed a beer in celebration truck ran fantasic, great throttle response, couldn't be happier. This being my first 392 the engine seemed waaay better than the 345 I recently put to bed. It burned off that new paint smell, no leaks to speak of. I was a happy guy.
We shut the truck down and proceeded to do some other tasks w/ the rollcage, seats ect... 15 minutes later we go to fire up the truck and nothing...... It spins and spins.... I pull the #8 plug to verify spark to the cylinders (been down this road before) and we are getting no spark. From this point we began to suspect something May be up w/ the dui unit itself. This engine has proven to be timed correctly, shutdown/restart several times and perform like an engine is suppose to.
No spark from any of the plug wires though... I was getting extremely frustrated at this point and decided to go a completely different direction. We pulled the entire dui unit out and put the dist/coil setup from my previous 345 into the 392. Timed off of #8 tdc, setup the timing light and dialed it in about 8 degrees btdc. This time the engine sounded completely different. We shutdown/restarted about 8-10 times attempting to prove we had no issues with spark. The engine sounded like it was missing and it didn't feel near as nice as when it ran well with the dui unit. But it always had spark and would fire immediately. I'm wondering at this point if there is a difference in running a dist/coil from a 345 on a 392??? We went ahead and reassemble the dui unit back on the engine and attempted to fire it up. No spark......
Per the instructions from dui and other threads on the board, I verified the input voltage to the dui unit to be 12.23. We used the same new optima battery for all the tests.
I really want to use the dui unit as it was a big investment, running perfectly, and was all that I expected it was going to be. It just seems like its acting erratically and not providing consistent spark.
I don't post out here much, I prefer to read, try, troubleshoot myself until I'm completely out of options. I'm hoping someone on the board can help me diagnose this issue. Its Saturday now and I'll be giving performance distibuters a call on Monday if I can't figure this out.
Thanks in advance guys!
