I have a question.. I know the 351w is supposed to
have a different firing order than the 302s, but if you have done a MAF conversion, and are running a mustang computer, then do you use the 302 firing
order? I guess cam/valve timing is identical between the two motors? I've been having a reoccuring problem.. The last 3 motors I've put in
my truck.. (this time I really spent a chunk of change) seem to have the center cylinders (3 and 7) running lean. I've moved the HEGOs (now they are IN the header collectors) thinking I had them
to far away.. I've changed injectors (went from stock 19s to 40s when I was supercharged, now back to 24s with normal aspiration).. I've recalibrated my MAF meter more times then I can
count.. disconnected my EGR.. now I am on a completely fresh motor, and though I haven't
pulled the plugs and read them yet, the exhaust has that wood stick slapping metal pop to it, and that usually means its running lean... no spark knock, and its not missing yet.. but I know when the mixture is right, with true duals and flow masters, I should get a hollow throaty sound out of the pipes... I KNOW my truck.. it doesn't sound right.. Just wondering.. If I'm using the wrong firing order.. would it still be smooth? Is the firing order close enough that the cylinders would still get fuel, and the truck would seem to run ok? It just doesn't seem to have enough power.. Its running good, and idles really smooth, but it just seems like something is amiss.. and its followed it
through several motors.. when I was supercharged, I actually melted 3 and 7 down.. (you could see down into the oil pan looking down with the heads off...... pistons 4".. cylinder walls 6"... it seems to be happening again.. The MAF kit came from ProFlo about 5 years ago and like I said, '93 Mustang computer... dual 4 wire HEGOs, and a 77mm meter... just wondering if
anyone else has done this conversion, and if anyone had the same problem I'm having.. I need to correct it before I smoke another motor.. I'm really close to ripping the fuel injection off and going with a carb...
thanks in advance
R/S

 

The proper firing order goes with the cam.

351/302HO is 13726548

Regular 302 is 15426378

Wire routing has to be watched on the regular 302 firing order. Keeping wires #7 & #8 far apart from each other. Otherwise, the spark of #7 can cross-fire plug #8 partway through its compression stroke, way too early. But if #8 cross-fires to #7, no big deal there, as #7 piston will be coming down in its power stroke anyway.

 

just a thought, if you swapped firing orders, did you adjust the fuel injector pattern? also, disconecting the egr is not a good idea, as the egr actualy briongs back some unpsent fuels and allows the computer to run a leaner mixture, so without it it may be a factor in your lean condition. just wondering how this effects your temperatture, and if you had a real temp gauge installed as opposed to that joke ford gauge. this lean condition should be causing high temperatures, right? there is no way you have the wrong plug wire order and are running in any drivable fashion.

 

Hey Rescue, go to this page. there is alot of great info on fuelinjection. Email ryan who runs the site. he has great knowledge of this stuff and would be able to help you the most


www.fordfuelinjection.com

later

 

Well, I had a million questions... I am running a Mustang puter, didn't know which EVP solenoid to get (Bronco, or Mustang, 302 Bronc or 351...?) I called Ford, and they needed a number of the motor that has long since been gone.. but I went back to my buddy's race shop today and he had a complete Bronco 302 with ALL of the goodies still on it.. I got the entire assembly for the EGR/EVP complete with all the factory vacuum hoses.. I had to do some modifying as my coil no longer resides where a factory coil does and all that bracketry is gone.. (wound up mounting the EVP on the driver's side firewall and extending the wires.. factory vaccum lines fit and reached as if it were made to go there.. and viola problem solved.. (well about 30 miles later and a few starts.. enough time for the computer to relearn) and I've got that beautiful exhaust note that its supposed to have.. might even be a tad rich now.. but thats ok by me.. sheesh I can't believe pumping exhaust back into the manifold effects my mixture THAT much... But like I said.. its pulling like a mule now.. The computer put all the advance back in the timing now that it is happy with the mixture.. I even got the Canister Purge and the Thermactor pump solenoids and plugged them back in (not hooked to vaccum, but they are present...) anyway, just got pulled over tonight on the way home.. 72 in a 45.. thank god I've got a get out of jail free card... even the cop said it sounded good...and said my new LED emerg lights were cool....thanks for the help guys..
R/S