What MAF and injectors for combo????????

[lovinspeed]

First, I was wondering what injectors and MAF I should get for the following combo. I am currently running with a stock fuel pump, injectors and MAF.

1991 Mustang 5.0
-SN93 Paxton Supercharger 7psi
-3.73 gears
-Edelbrock RPM upper and lower intake
-Complete exhaust, Headman Headers, Flowmaster Mufflers
-E303 cam
-Battery relocation

Second, how big of injectors can you have with the stock fuel pump?

Third, how hard is it to install new injectors?

Lastly, how much horsepower would be freed up, by putting in recommended injectors and MAF?

Thank you for any help

 

[Strype]

Second, how big of injectors can you have with the stock fuel pump?

Third, how hard is it to install new injectors?

19 lbs with stock- the stock fuel pump is just adiquate... in other words it sux... well I guess it blows- haha I made a funny!

Upgrade to a 255 if supercharging

Injectors are easy as pie... just take the upper manifold off, press the reset button on the fuel cutoff switch by the tail lights, and start the car over a couple of times to burn up extra fuel.

 

[lovinspeed]

re

Can anybody answer my questions

Thanks for the reply Strype

 

[GreatWhite]

Get some heads

 

[JChalfan]

Are you currently running the FMU with your Paxton? If so, you can get away with the stock 19lb injectors, though it's not the best way to do it. You definitely need a 255 fuel pump no matter what you do.

The best thing to do is ditch the FMU and get a set of big (42lb I think) injectors and a MAF that's calibrated for them. Then take it to a shop and have them burn you a custom chip.

I'm currently running 24lb injectors and an FMU with my Paxton SN92. It works fine, but there's more power to be had with a good tune and big injectors.

Jeff

 

[lovinspeed]

re

Thanks for the reply JChalfan.

Yes I am currently using the FMU. How would I ditch the FMU? What size MAF should I get? How much power gains can I see from this?

Thanks again

 

[JChalfan]

Thanks for the reply JChalfan.

Yes I am currently using the FMU. How would I ditch the FMU? What size MAF should I get? How much power gains can I see from this?

Thanks again

The FMU works by increasing fuel pressure as boost increases. This forces more fuel through the 19lb injectors than they are designed to deliver, since with stock fuel pressure they can't flow enough fuel for the supercharger.

Before you can ditch the FMU, you need the bigger injectors and matched MAF. I would probably recommend a 90mm MAF. At LEAST 73mm. Once you get the bigger injectors and MAF, you simply remove the FMU from the fuel return line and plug the vacuum port it's hooked into. At that point you really should get it dyno tuned and have a custom chip burned.

I'm not sure exactly how much power you will gain from this, since I haven't done it yet on my car. However everyone says you will gain noticable power, and drivability will improve.

You should check out the forums over at superchargerhelp.com. Check the SN series forum, those guys really know their stuff.

Jeff