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dual power adder with hyperfuel stalls runs rough

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I have ha a heck of a time getting my temperature under control  and I finally have it running between 185 and 201, but out on my test drive toady it all of a sudden acted like it ran out of fuel, first power loss and running rough I could not keep it running and it died it did restart  but ran rough with a bad miss I let it cool and sit for ten minutes or so and made it the 1.5 mile run home but did not run as good as I had it before it acted up, I did go to a cooler plug by 2 ranges cooler, I am not sure if it is a plug issue or the fitech ,,,the other day it stumbled in my garage after letting it idle for about 45 minutes I played with the throttle revved it up a few time and it straightened out, I am going to change the plugs back to the 3924 and try that ,, my hyper fuel unit is about a foot and a half away from any engine heat from the head or headers all my nylon braided line are away from all heat sources as well I have plastic spacers under the throttle bodies but ill do that and trouble shoot other items and see what I might find and report back

okay I installed a NEW ignition box, 3 step retard, blaster 2 coil, msd distributor pick up coil, new double platinum plugs. It fired right up and ran for about 30 seconds and started to miss real bad running extremely rough black smoke pouring out the exhaust I I accelerated it up to about 4 to 5000 rpm it would smooth out but when you let off it went back to running like crap WAY rich dumping the fuel in it my garage os 24x30 10 foot walls with 18 foot peak  and it damn near looked dark in there with the lights on I don't know what in the world could cause this my afr readings was 13.1 obviously not right ,,,,,,,,,WTF time to go to edlebrock 1912 carbs and sell the fitech....unless anyone has a clue im about over this fitech and very disappointed in it after all it cost and its SO NOT user friendly let me know if anyone has any ideas I believe ill try a new post and see if I can get responses,.,.

Small exhuast leak could cause this.  Air in the exhaust, yields lean O2 reading, yields more fuel.  Runs rich, O2 sensor has correct reading.

okay i received the new o2 sensor i will install it tomorrow, there is 0 leaks in the exhaust system custom fpa headers with a really good header gasket ,o2 is in the header just before the collector and clocked correctly then it goes into 3 1/2 side pipes.

okay i installed the new eBay o2s and the car fired up and ran thank god i then took it out on a 3 mile test drive and it only had a slight erratic miss at cruse speeds except when i gave it a 1/4 throttle it pulled like a monster smooth steady and hard then the tires went up in smoke (i need slicks) i did remove the AR3934 plugs and went with a set of autolites double platinum plugs 2 degrees hotter and gaped at .035 and after some reading i should be the other way at a AR3931 gaped at between .025-.028 am no longer totally sold on this system its just way to difficult to adjust seems like you adjust it more than it adjust itself  and my o2s went bad after a total of only about 10 miles i am thinking i need to carry a spare and a 3/4 wrench so now i am off to figure out this slight miss at cruse but every plug i have put in this is still the same but ill make the ar3931 change and see i all ready swapped out the coil mag coil cd box and 3 step the wire are all new too they are the Taylor 8.8 wires heads and valve train all new valve lash was set on each valve 1 at a time no exhaust leaks and i did not see and intake leaks but even if the fuel injection was say like it had a misfiring injector with it on top of a roots blower you wouldn't be able to tell because all the fuel and air is pummeled all together and forced into the cylinders

i also removed the autolite double platinum plugs and installed the ngk 6596 it is a cooler plug that is supposed to run with blower or supercharger applications attached is a double platinum plug it was installed after the new 17014 o2s was installed and according to what i see on the plug it is running right where it should be all the plugs read exactly the same.

 

 

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okay this motor don't like the 17104 plugs I put a new set of yhe 3924 autolites in and runs allot better I did send fitech some cranky mail to there tech dept on the failed o2s and to my surprise they are sending me a brand new one at no charge ill half to keep it in the car with a wrench and small jack to avoid any future tow bills may have been just a bad sensor that got by qa but just apprehensive right now

Quote from taylorteamracing on September 21, 2019, 11:08 am

okay this motor don't like the 17104 plugs I put a new set of yhe 3924 autolites in and runs allot better I did send fitech some cranky mail to there tech dept on the failed o2s and to my surprise they are sending me a brand new one at no charge ill half to keep it in the car with a wrench and small jack to avoid any future tow bills may have been just a bad sensor that got by qa but just apprehensive right now

The Fitech O2 sensors are sourced from Bosch.  Very reliable sensors.  But, sometimes things happen.

So looking at you plug pic, you are still fat. And it could use another degree of timing. I ended up at .18 on the plug gap.

I advanced the timing more and kept the 3924 plugs in re did the gap and I also leaned target afr to 13;5.1 runs allot better

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