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AFPR Questions

  • Thread starter Thread starter Mattys5Oh
  • Start date Start date Sep 13, 2004
M

Mattys5Oh

Founding Member
Sep 28, 2002
216
0
0
Western, Mass
Sep 13, 2004
#1
  • Sep 13, 2004
  • #1
I should be receiving my AFPR towards the end of the week and have a few questions.

I had the car dyno'd a while back (Jan. 04) and was running a 9:1 A/F with the stock regulator. It was running so rich that it turned his "sniffer" off during the run. I know, crazy huh.

Since then I have added a 75mm MAF, Explorer intake, and Explorer 19lb "disc-style" injectors. I am still getting alot of gasoline fumes from my exhaust.

My question is......(Since I don't have any access to a dyno to tune it) What FP and timing should I try it at?

Also, if you need to know anything additional to the combo, let me know.

Thanks,
Matt

*EDIT* Also wanted to add that my buddy thinks my car is running in "limp mode" to save it from detonation, but would it run THAT rich??
 

jrichker

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In Remembrance. Thank you for your contributions
Mar 10, 2000
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Dublin GA
Sep 13, 2004
#2
  • Sep 13, 2004
  • #2
Use the SOP meter...

Get one of your buddies to ride along with you. Find a level stretch of road where you can do some testing. Don't choose a speed range that will make you shift gears, the shift quality & speed will affect your results. Use 2nd or 3rd gear and do a run from 2000 RPM to 5800 RPM. Call out the RPM as it increases and have you buddy record it and the elapsed time. If you have one of those cheap digital watches like I do, a stop watch is built in. Start the fuel pressure at 36 PSI, vacuum off and make a run. Turn it up to 37 and make another. Be sure to reconnect the vacuum every time you set the pressure. Keep turning up the pressure and making runs until you notice a drop off in time. If your bud was careful to record the results, you'll have a nice chart to use to find the optimum pressure.
 
M

Mattys5Oh

Founding Member
Sep 28, 2002
216
0
0
Western, Mass
Sep 13, 2004
#3
  • Sep 13, 2004
  • #3
jrichker said:
Use the SOP meter...

Get one of your buddies to ride along with you. Find a level stretch of road where you can do some testing. Don't choose a speed range that will make you shift gears, the shift quality & speed will affect your results. Use 2nd or 3rd gear and do a run from 2000 RPM to 5800 RPM. Call out the RPM as it increases and have you buddy record it and the elapsed time. If you have one of those cheap digital watches like I do, a stop watch is built in. Start the fuel pressure at 36 PSI, vacuum off and make a run. Turn it up to 37 and make another. Be sure to reconnect the vacuum every time you set the pressure. Keep turning up the pressure and making runs until you notice a drop off in time. If your bud was careful to record the results, you'll have a nice chart to use to find the optimum pressure.
Click to expand...

Good idea. I think I understand. Samething with the timing or would it matter if I keep the timing set at 13-14*?


Matt
 

nito88stang

Founding Member
May 23, 2002
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0
46
Fullerton, California
Sep 13, 2004
#4
  • Sep 13, 2004
  • #4
So is everything stock and you just have gears and exhaust like it says in your sig? If so, then there is definitely something wrong with your car if its running that rich with a stock FPR on a stock longblock. An AFPR at this point will only be a band aid. Find out whats wrong first. Your o2 sensors may be shot and ur car is throwing a lean condition code or your MAF may be dirty. Could be many things. Run for codes first.
 

jrichker

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Sep 13, 2004
#5
  • Sep 13, 2004
  • #5
Mattys5Oh said:
Good idea. I think I understand. Samething with the timing or would it matter if I keep the timing set at 13-14*?
Matt
Click to expand...

As long as you don't change anything but the fuel pressure, the results will be accurate. You can put the timing at any setting that makes the car run good consistently.

nito88stang said:
So is everything stock and you just have gears and exhaust like it says in your sig? If so, then there is definitely something wrong with your car if its running that rich with a stock FPR on a stock longblock. An AFPR at this point will only be a band aid. Find out whats wrong first. Your o2 sensors may be shot and ur car is throwing a lean condition code or your MAF may be dirty. Could be many things. Run for codes first.
Click to expand...

Good point... Here's the link 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.

See http://www.troublecodes.net/Ford/
OR
See http://www.dalidesign.com/hbook/eectest.html for more descriptive help
OR
See http://www.mustangworks.com/articles/electronics/eec-iv_codes.html

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.

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.

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

For those who are intimidated by all the wires & connections, see http://www.actron.com/product_detail.php?pid=16153 for what a typical hand scanner looks like. Normal retail price is about $30 or so at AutoZone or Walmart.
 
M

Mattys5Oh

Founding Member
Sep 28, 2002
216
0
0
Western, Mass
Sep 13, 2004
#6
  • Sep 13, 2004
  • #6
nito88stang said:
So is everything stock and you just have gears and exhaust like it says in your sig? If so, then there is definitely something wrong with your car if its running that rich with a stock FPR on a stock longblock. An AFPR at this point will only be a band aid. Find out whats wrong first. Your o2 sensors may be shot and ur car is throwing a lean condition code or your MAF may be dirty. Could be many things. Run for codes first.
Click to expand...

O2's are less then a year old and MAF is also fairly new. And if it's a band aid that works I don't care. This car will probbaly be apart by next summer anyways.

Mods are as follows when car was dyno'd.

Comp Cams 1.72 Roller Rockers
ASP Underdrive Pullys
MAC Cold Air Intake
BBK Unequal-length shorty headers
Off-road H-pipe
3 chamber Flowmasters with no tail pipes or dumps (MAC cat-back coming soon) (I have a feeling the exhaust set-up is making it run so rich)
Steeda Tri-Ax shifter
SVO clutch quadrant with adjustable cable
FRPP 3.55 gears
Lakewood 50/50 shocks

Mods added since dyno.

75mm MAF
Explorer Intake
Explorer 19lb disc style injectors


Matt
 
M

Mattys5Oh

Founding Member
Sep 28, 2002
216
0
0
Western, Mass
Sep 14, 2004
#7
  • Sep 14, 2004
  • #7
TTT
 
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