Yep! Old thread, I never saw this post...but to answer the question..My car got 14.3 mpg on the interstate going to Summit and back one day,Thats the only time I `ve ever checked it. I`ll bet that if I swapped the tunnel ram for a Performer RPM with a 650 on it,that my mileage wouldn`t improve at all. The car would still have a 308 with an X-303 cam, 3,800 rpm converter, and 4.11 gears . The thing about dual carbs us almost everyone instantly thinks "Wow ! I`ll bet that thingfreally drinks alot of gas!" Here is some food for thought: You cannot run an engine on ALOT More gas or will be really rich right? When running Two carbs the engine IS NOT using twice as much fuel.If it were, it would be so rich it would either Flood itself out or wash out the cylinders with all that gas and eat up the rings in a hurry. You see I have two 450 cfm carbs (yes I know that equals 900 cfm ) They have butterflys about the same size as a Quarter. The carbs have also been jetted Down to deliver less fuel than they did out of the box. The engine has been in the car for going on seven years now and is about as driveable as any similar V-8 old Hot rod I know of. the people on this board who have been around it will attest to the cars street manners and performance. It will start right up weather its 100 degrees or 28 degrees outside (done both many times) and will cruise around town without loading up,or acting up in any way. Also does good interstate cruising with the exception of the 4.11`s creating high cruise RPM`s People ask "Yea ,but will that `lil motor "take" all that carb and intake when you jump on it....Yea, It will! I`ll shut up now since this thread is supposed to be about Fuel injection. I was just in a typing mood I guess which only happens with me about once a year. (Just ask Jamie!)
alright.. so i believe you may be able to help me.. i have 91 5.0 in my 70, i have a painless harness not yet in the car though.. still sitting in the box lol. but i have a few codes.. *67.. witch is my park neutral switch. reason for that is, i got rid of the AOD, and went back to a C4, so i reconnected the wires, on my b&m megashifter. idk how to bypass the code.. *81 secondary AB circuit failure *82 secondary AD circuit failure i know i dont have the EGR setup cause my dad got ride of it when he did the conversion in 09, but is that the reason those codes show?
Just removed all of the EFI stuff to simplify! I'd have to look up the codes but I'm sure without the EGR codes are likely. With the nuetral switch it may not recognize the shifter vs the AOD. Not sure. All of the codes can be bypassed if you have someone with the ability to modify the ECM.
I have the same codes for the same reason. I deleted EGR and the secondary air system(smog pump, etc) The automatic ECU is looking for 12v in neutral and the manual ECU is looking for signal return(signal ground) which sets the code 67 I believe. 81 and 82 are the secondary air solenoid circuits. None of these will cause driveability issues, with the exception of the neutral switch and it may cause a slightly high idle depending on the ECU.
