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Discussion Starter #1
Need little help with power I have 87 foxbody newer engine like 4000 miles on I mad coil and distributer bbk headers flow master H pipes 75 mm throttle body and spacer coil air intake new 24 lb fuel injectors but the only way I can explain it is like something is holding the car back smog pump and ac have been all taken out as well the rear end has been belt up with3.73 gear new def and 31 spline axles can y'all think of anything
 

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Need little help with power I have 87 foxbody newer engine like 4000 miles on I mad coil and distributer bbk headers flow master H pipes 75 mm throttle body and spacer coil air intake new 24 lb fuel injectors but the only way I can explain it is like something is holding the car back smog pump and ac have been all taken out as well the rear end has been belt up with3.73 gear new def and 31 spline axles can y'all think of anything
Do you have the proper maf. If you are using
the stock 19lb maf that could be your problem.
 

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Discussion Starter #3
Well shi- thanks I'll check it out hope that does the trick got the car to learn to work on them and yeah
 

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Discussion Starter #5
how would an 87 mustang act if you have 24 lb fuel injectors in and the map sensor is set for 19 lb injectors
 

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how would an 87 mustang act if you have 24 lb fuel injectors in and the map sensor is set for 19 lb injectors

Excuse me I forgot 1987 mustangs have
speed density, not mass air, Usually when you
make any intake or cam changes you need
to convert to mass air. The speed density
system isn't capable of adapting to the new
engine changes.
 

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^^^^^^

I second that movement.

Im not even sure how your engine is even running with 24#lbs without modifiying the fuel control. With the setup you say you are running, you should be fine with the stock 19ers. From what ive read, 19s can support about 300hp at the limit. You are not pushing close to 300 on a stock long block 302 with a few bolt ons (no offence, but its the truth) \

You have two options to get your car running properly.

1- Put the 19# fuel injectors back in

2- Convert to MAF, and get an aftermarket mass air that is calibrated to trick the ecu into running those 24# injectors without running your motor rich as hell. Which I can promise you, you are if you just slapped 24's in and did nothing to change how the ECU fires the injectors.

Option 2 is ideal. Infact, with your mods I would put the 19s back in and swap to MAF. The 19s can handle what you are running no problem. Keep the 24s on the shelf until you do some serious mods like heads, cam, etc. Thats when your going to need them.

Oversizing injectors compared to your setup does NOTHING to give you more power. At all.
 

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Discussion Starter #8
Yeah cam and heads are on the bench now just haven't had time to put them on and 24 lb maf is on the way now so sounds like once I get all these things on I'll be good
 

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When I first got my 86, it had an edelbrock intake manifold, long tubes and o/r mid, BBK fender intake, and 24 lb injectors....that thing ran like a beast! No MAF, no tuning, but something about it ran very very well, very strong. I had tracked down a vac leak to the upper intake ear, broken. I switched to a stock intake, and car ran like POOP. Put on 19 injectors, and it ran much better.

Point being, it can be run on 24# with no maf, but probably only in a very specific combo like above. Was it optimal? Prob not, but it did run stronger than it did after changing to stock intake/injectors.
 

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without converting the car to Mass Air your speed density will contiue running the program for all the stock parts and you will see the car become a dog more and more you have to convert the car to mass air for the improvements your doing the MAF sensor you ordered is great but if your not converted it has nothing to plug into and read it.
 

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you can send out your ecm to be reprogrammed for the parts you have installed but each time you change something you have to program it again.
 

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Discussion Starter #12
I read on another post on here someone say that you can just get the maf sensor and get an 89 maf harness and then just plug it all in is this have any truth in it
 
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