Slow 94 5.0

Heads.

I take that you are running 9's on a 1/8 mile track.

Start looking for simple things like codes, ignition problems, clogged fuel and air filters. The NO2 is going to make you decrease the spark gap down to .035 to insure that it doesn't blow out. A fancy ignition box with retard for NO2 would be a good idea.

New fuel and air filter would be next.
What size fuel pump are you running with the NO2? A 125 shot will starve for fuel if you use the stock fuel pump.

Then dump the codes and fixing the ones that pop up.
Dump the codes: Codes may be present even if the Check Engine Light (CEL) isn't on.

Dumping the computer diagnostic codes on 86-95 Mustangs

Revised 26-July-2011. Added need to make sure the clutch is pressed when dumping codes.

Codes may be present even if the check engine light hasn’t come on, so be sure to check for them.

Here's the way to dump the computer codes with only a jumper wire or paper clip and the check engine light, or test light or voltmeter. I’ve used it for years, and it works great. You watch the flashing test lamp or Check Engine Light and count the flashes.

Post the codes you get and I will post 86-93 model 5.0 Mustang specific code definitions and fixes. I do not have a complete listing for 94-95 model 5.0 Mustangs at this time.

Be sure to turn off the A/C, and put the transmission in neutral when dumping the codes. On a manual transmission car, be sure to press the clutch to the floor.
Fail to do this and you will generate a code 67 and not be able to dump the Engine Running codes.





If your car is an 86-88 stang, you'll have to use the test lamp or voltmeter method. There is no functional check engine light on the 86-88's except possibly the Cali Mass Air cars.



The STI has a gray connector shell and a white/red wire. It comes from the same bundle of wires as the self test connector.

89 through 95 cars have a working Check Engine light. Watch it instead of using a test lamp.



The STI has a gray connector shell and a white/red wire. It comes from the same bundle of wires as the self test connector.


WARNING!!! There is a single dark brown connector with a black/orange wire. It is the 12 volt power to the under the hood light. Do not jumper it to the computer test connector. If you do, you will damage the computer.

What to expect:
You should get a code 11 (two single flashes in succession). This says that the computer's internal workings are OK, and that the wiring to put the computer into diagnostic mode is good. No code 11 and you have some wiring problems. This is crucial: the same wire that provides the ground to dump the codes provides signal ground for the TPS, EGR, ACT and Map/Baro sensors. If it fails, you will have poor performance, economy and driveablity problems

Some codes have different answers if the engine is running from the answers that it has when the engine isn't running. It helps a lot to know if you had the engine running when you ran the test.

Dumping the Engine Running codes: The procedure is the same, you start the engine with the test jumper in place. Be sure the A/C is off, and clutch (if present) is pressed to the floor, and the transmission is in neutral. You'll get an 11, then a 4 and the engine will speed up to do the EGR test. After the engine speed decreases back to idle, it will dump the engine running codes.

Trouble codes are either 2 digit or 3 digit, there are no cars that use both 2 digit codes and 3 digit codes.

Your 86-88 5.0 won't have a working Check Engine Light, so you'll need a test light.
See AutoZone Part Number: 25886 , $10




Alternate methods:
For those who are intimidated by all the wires & connections, see Actron® for what a typical hand scanner looks like. Normal retail price is about $30 or so at AutoZone or Wal-Mart.

Or for a nicer scanner see www.midwayautosupply.com/Equus-Digital-Ford-Code-Reader/dp/B000EW0KHW Equus - Digital Ford Code Reader (3145It has a 3 digit LCD display so that you don’t have to count flashes or beeps.. Cost is $22-$36.

He didn't say it was running bad, stock headed 302's are just slow is all.

A proper Heads/Cam/Intake package will give you solid gains, but it'll need a decent tune. Whether Mopar, Ford, or GM, the induction system needs to be viewed as a complete system. Upgrading one part (which might not match the others) will not necessarily provide a good gain.

Sharad said:

A proper Heads/Cam/Intake package will give you solid gains, but it'll need a decent tune. Whether Mopar, Ford, or GM, the induction system needs to be viewed as a complete system. Upgrading one part (which might not match the others) will not necessarily provide a good gain.

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'Tis the nature of the bolt-on game.

Daddys girls GT's said:

Thanks folks! Yes she runs the 1/8th. I changed jets down to 100 hp and runs a flat 9 spraying. I would like other options before doing heads. My intent is to build a nice motor and swap at some point (I still have a 14 yr old to buy a car for though). Would equal length shorty headers help? Long tube is not an option due to clearance (we live in the mtns). Then a tune would be next but do I get the chip online or take to the guy in Charlotte, NC?

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Shorty headers- I'm gonna have to say no sir. I hate to sound like a broken record but one really has to dump some money into these cars to get them anywhere near respectable since we're starting so far behind the curve from the factory, 215 crank horsepower. The "bolt-on" game isn't going to get you very much at all and it'll nickel and dime you to death. I don't have any drag times but here's a story of a man named Brady: With fresh motor with e7 heads and .512 lift cam I made 202 rear wheel horse through a 5 speed. I then had the lower intake (efi) ported, added cold air intake(yes I know jinky), deleted the pre-cats and replaced the aft cats with high flows and replaced rusty flowmasters with a new ones.- I made 223 rear horse. While I could tell it had a little more pep in its step, even with the 3.73 gears she still might have er hands full taking on a new Camry or the likes. I've since added a centri blower and now we're movin', well respectably movin'. It's still not as fast as the modern hotrods but I'd say it might be comparable to an off the showroom floor '00 Z28. I don't have any new dyno #'s but I have an appointment in Sept. So the moral of the story my friend is one has to either get a new topend or buy a blower just to be on par with a stockish Camaro/Firebird of the same year. It's frustrating.

Daddys girls GT's said:

Thanks a lot! I really appreciate the help 90lx and jrichker. I do have the code reader and did dump codes but only had 3.
118 A coolant temp sensor code which is due to going with a mechanical
334 EGR valve code but I did eliminate EGR completely
564 Electro fan code....no idea why that was an issue though
Anyway, cleared em all and runs about the same. In the past 2 months I have cleaned air filter, replaced most of the engine sensors and the fuel filter. Still have stock fuel pump and injectors. Only issue with the 125 shot was valves rattled even at degrees BTC timing but did pickup a full second. I put 100 shot back in and timing at 12 degrees BTC again, runs 9.03 now. If I did heads and 1.7 rocker arms along with the equal length shorty headers am I going to get a punch? Do I still need to do a tune? Use mail order or local tuner? I really don't wanna tear the cam out at this time is my biggest concern!

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if I'm not mistaken the Cobra had the same cam as the GT's along with 1.7 rockers to go with their gt40 heads. Heads will help, get the best set you can afford. If you're purchasing new wouldn't go with ford racing's gt40x (aluminum) just because they are only a tad cheaper than say a Trick Flow and the latter will gain you more. Oh and by the way the dyno numbers I mentioned earlier were on a 95 gt