Please recommend me a MAF for this set up...

I am not planning on going supercharged or anything like that. Just a 300hp daily driver type of set up. I got the car from a guy and I can't be sure of everything but it appears he had a stock MAF on the 90mm intake elbow and the car runs like crap, throwing EGR and 'Too Lean' codes, fluctuating idle and dying. I have checked extensively for vacuum leaks but to no avail (I had a whole thread on it) so I have determined that the MAF situation is the next step in trouble shooting.

So, I either need to up/downgrade my intake set up or I am wondering if a tune might fix this. Supposedly it is running 21lb injectors too if that helps. Any suggestions or advice would be appreciated.
 
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I am not planning on going supercharged or anything like that. Just a 300hp daily driver type of set up. I got the car from a guy and I can't be sure of everything but it appears he had a stock MAF on the 90mm intake elbow and the car runs like crap, throwing EGR and 'Too Lean' codes, fluctuating idle and dying. I have checked extensively for vacuum leaks but to no avail (I had a whole thread on it) so I have determined that the MAF situation is the next step in trouble shooting.

So, I either need to up/downgrade my intake set up or I am wondering if a tune might fix this. Supposedly it is running 21lb injectors too if that helps. Any suggestions or advice would be appreciated.
Hi,
If you did a write up, can you 0lease paste it here? Very helpful knowing what mods have been done, you don’t want to tune it until all your bugs are out of it. 21lb injectors if matched to sallee injectors will generally make it run rich, may be a big air 90mm MAF.
What’s your fuel pressure?
Any exhaust leaks?
What codes has it thrown?
Exhaust system stock, aftermarket?
Set the TPS to <1VDC at idle?
Plugs color, oily, carbonized, clean, tan, etc?
Running stock injectors?
How does the car run cold vs warm- different?
Quite helpful if you can post a new engine pics, and what the motor has had done internally. But in the dark, happy to help.
Best!
John
 
A 90 maf on a stock car could be a huge problem if not tuned probably.
And still a problem even if tuned properly..

A stock type car, with a few bolt on’s.
Would be much better off with a stock ford maf.
Getting 300 hp out of a mod motor will take ported heads, and a good cam, a bit more compression and fuel/air support as well...we chased 300 hp in mod motors for years...it’s not easy. But can be done.

Below is a few pages of the sizing of fuel injection components.

with a maf it’s best to size it to hp.
If you go overboard it will only hurt the overall tune.

 
Differences in maf transfer curves.
Get this wrong, car runs bad.

Stock - Ford 1999 - 2004 Mustang GT
VoltageFlow
16.001220.0
5.001145.0
4.75990.0
4.50859.0
4.25728.0
4.00616.0
3.75510.0
3.50430.0
3.25350.0
3.00285.0
2.75223.0
2.50173.0
2.25135.0
2.00102.0
1.7576.0
1.5055.0
1.2539.0
1.0025.8
0.7517.3
0.5010.5
0.256.0
0.052.0
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
80mm Lightning
VoltageFlow
16.001552.3
5.0001552.3
4.6431244.3
4.4471097.4
4.252964.28
4.056843.58
3.861734.00
3.665634.61
3.470544.47
3.274463.37
3.079391.14
2.883327.21
2.737284.21
2.590245.36
2.443210.66
2.297179.54
2.150151.82
2.003127.49
1.857106.18
1.71087.50
1.56471.28
1.41757.52
1.27045.45
1.12435.26
0.97726.59
0.85520.55
0.73315.27
0.63511.88
0.5629.80
0.0004.149
90mm Ford Lightning / 03-04 Cobra
VoltageFlow
16.001686.63
5.0001686.63
4.8391485.72
4.6791342.28
4.5181220.06
4.3581104.82
4.198993.50
4.037887.583
3.877789.320
3.717700.066
3.556619.84
3.396547.64
3.236481.96
3.075421.43
2.915365.14
2.755312.87
2.594264.95
2.434222.05
2.274184.78
2.113153.36
1.953127.42
1.793106.00
1.63287.71
1.47271.25
1.31255.85
1.15141.76
0.99130.16
0.83122.19
0.67016.37
0.0005.50