Eec-iv A9l = C3w1

Treachery · 10-04-2005, 08:08 PM

I went to Ford parts and said that i wanted to get a replacement EEC-IV (A9L) for my 93 Mustang GT (manual transmission)

The replacement received was labeled (reman) C3W1.

I did some research and soon discovered that C3W1 is for Automatic Transmission.

I called Ford parts the parts person said that the C3W1 is an "updated part number". I asked him to double check and upon checking, he said that the C3W1 is good for both manual & automatic transmissions.

Is he correct? I'm going to have a custom chip burned because of a blower install.

Jeff Chambers · 10-05-2005, 06:58 AM

Yes, it is interchangeable.

Treachery · 10-05-2005, 06:36 PM

Are the air/fuel curves the same?

I installed it and now my Mustang pings at WOT.

Jeff Chambers · 10-06-2005, 09:35 AM

There are some differences to the A/F and spark tables. In short, the C3W1 has richer base fuel values but a less WOT fuel fuel multiplier so it works out to almost the same. The C3W1 is commanding about 5.5-degrees more spark at WOT throttle than the A9L so that might be the cause of the pinging. You'd need a custom tune to change these things. Have you tried running premium fuel?

fiveohpatrol · 10-06-2005, 04:24 PM

FWIW, I have the C3W1 in my car and it's been great

10-04-2005, 08:08 PM	#1
Treachery Registered Member Join Date: Jul 2002 Posts: 38	Eec-iv A9l = C3w1 I went to Ford parts and said that i wanted to get a replacement EEC-IV (A9L) for my 93 Mustang GT (manual transmission) The replacement received was labeled (reman) C3W1. I did some research and soon discovered that C3W1 is for Automatic Transmission. I called Ford parts the parts person said that the C3W1 is an "updated part number". I asked him to double check and upon checking, he said that the C3W1 is good for both manual & automatic transmissions. Is he correct? I'm going to have a custom chip burned because of a blower install.

10-05-2005, 06:58 AM	#2
Jeff Chambers Moderator Join Date: Aug 2000 Location: Milan, OH Posts: 2,699	Re: Eec-iv A9l = C3w1 Yes, it is interchangeable. __________________ Jeff Chambers 1990 Mustang GT 10.032 Seconds / 137.5 MPH 14-time Street Warrior World Record Setter CRT Performance 2001 Tropic Green Mustang GT - 12.181 / 113.2 MPH 2002 Ford F-250 Crew Cab 7.3l Power Stroke - 17.41@77.2 "There's nothing boring about a small block automatic shifting gears at 9400 rpm!"

10-05-2005, 06:36 PM	#3
Treachery Registered Member Join Date: Jul 2002 Posts: 38	Re: Eec-iv A9l = C3w1 Are the air/fuel curves the same? I installed it and now my Mustang pings at WOT.

10-06-2005, 09:35 AM	#4
Jeff Chambers Moderator Join Date: Aug 2000 Location: Milan, OH Posts: 2,699	Re: Eec-iv A9l = C3w1 There are some differences to the A/F and spark tables. In short, the C3W1 has richer base fuel values but a less WOT fuel fuel multiplier so it works out to almost the same. The C3W1 is commanding about 5.5-degrees more spark at WOT throttle than the A9L so that might be the cause of the pinging. You'd need a custom tune to change these things. Have you tried running premium fuel? __________________ Jeff Chambers 1990 Mustang GT 10.032 Seconds / 137.5 MPH 14-time Street Warrior World Record Setter CRT Performance 2001 Tropic Green Mustang GT - 12.181 / 113.2 MPH 2002 Ford F-250 Crew Cab 7.3l Power Stroke - 17.41@77.2 "There's nothing boring about a small block automatic shifting gears at 9400 rpm!"

10-06-2005, 04:24 PM	#5
fiveohpatrol I'd rather be basketweaving Join Date: Feb 2000 Location: Indianapolis Posts: 2,551	Re: Eec-iv A9l = C3w1 FWIW, I have the C3W1 in my car and it's been great __________________ NMRA O/C 9516 NA pumpgas stickshift 347 10.65@125.6, 6.73@100, 1.41 60ft