Mustang 19lb Fuel Injectors

I recently purchased a set of Mustang 19lb Fuel Injectors and a Mustang 70mm MAF with IAT sensor to match the 19lb injectors. But I’m worried, even though I have done my research.

Will the compression be too much?

Will my stock fuel pump be able to keep up?

Will the stock fuel rail be too small?

If anyone else has done this modification, tell me how it worked out for you. And any suggestions you might have, leave some info on this tread.

I havent done this yet, but from my understanding you should be allright.

changing your injectors shouldn’t change your compression ratio.

With the stock fuel pump youll probably max the pump out before you max out the 19lb injectors.

as for the stock fuel rail, i cant recall hearing that anybody changed them out…

If im wrong someone please correct me. BTW welcome to the site!!!

I was only worried that if the compression ratio remains the same but am adding more fuel and air would cause pre-detonation, inwhich case I just use a high octane level. The fuel pump may need to be upgraded, but figured that with it only being 19lb injectors, the next level up, the pump shouldn’t have too much of a problem keeping up.

I will post how the mod worked for me. Should be a good power adder.

I have been running the 19lb injectors for about a month now, so far no problems, however i have an S/R comp and always run 93 octane fuel and I don’t have the the 70mm MAF installed. You should run into absolutely no problems at all running the 19lbs injectors. Did you get the MAF from the mustang? does that directly replace the stock MAF? I’ve heard of people doing this but haven’t found anything about it.

Yeah, but you have look for the specific MAFs.

I got one from a 2002 Mustang. For now, my guess is that 2002 and newer models have the 6 pin setup. The older models have a 4-pin setup and are only a MAF sensor.

The newer models have a MAF and include an IAT sensor. (I believe that the IAT measures temperature)

I have upgraded to a 3-inch intake. The 70mm MAF should be a direct replacement because the aftermarket intake included a MAF adapter. I currently don’t have the new MAF in my possession, but it should fit.

I will post pictures of the install later.

why’d you buy 19 lb/hr injectors if the ZX2 already comes with them?

The Z doesn’t come with 19lb injectors, the stock injectors are 16 pounds

Gitt24_84 is right. The Zx2 comes with 16lb injectors.

So I got some 19lb from a Mustang. And I went with 19 pounders because I didn’t want to take a leap into bigger injectors and risk blowing the engine or something.

For me, this is all uncharted territory. Yeah, you can read about it in articles or forums. But you can’t get a full grasp of it till you do it. And I’m not going to dive unless I’m 100%. So I’m just steping it up by 3lbs.

(Just to let you know, I’ve been around ZX2’s for along time)

The stock injector size is 19 lbs/hr. There was a huge debate over at TeamZX2 about it sometime ago, with BOSS_122 finally proving it. You won’t need to change your injectors until upwards of 180hp, so there is no need for it unless you plan on going FI (which is tough with a returnless fuel system like ours.).

I’m working on finding you the link so you can read for yourself.

Yeah, when you do find that link. Clue me in. I might feel like and idot after buy the injectors, but I’ll get over it.

Hey pip, I had this discussion with a bunch of guys awhile ago and we ended up talking to the Ford dealership, they said 16lbs, now you’ve got me confused, so like mirrorguardian I went and bought the 19 pounders…Only after I had verified with the Ford guys, now I do realize that all dealerships, no matter what brand are f’n retarded but…I’d like to see the link too pip cause then I’ll feel like a douche… :shock:

Well, I finally changed out the injectors because I received the 70mm MAF I was waiting for.

After putting both in, I went for a test drive. It was horrible. It was SUPER sluggish. And it would almost stall.

I have concluded that the MAF was a bad idea. Re-installed the old MAF (stock) and it worked like a charm. There were some noticeable differences too. It was a clean RPM range up and through 3k RPMs. Also at the top end, where it would normally cry “why are you pushing me so hard,� it kept up till the shifts.

That’s all I got for now. I’m still working on it though.

I saw on the Thread you provide that everyone is saying that the stock injectors are 19lb. I just can’t get over the fact that there is a considerable size difference. I will get a picture up for all to see.

I did read that “if” they are the same size, the difference is that the mustang injectors have a better spray. That maybe true, because under 3k RPMs the pull is stronger.

But you ran Ford; you could mass-produce 19lb injectors for the Mustang, Focus, and Zx2 for a cheaper price. Why would they change the style of injectors/size of the injectors if they all are 19lb injectors. You would actually spend more money with 2 or 3 versions of same LB. injectors. It’s not even like the one sized doesn’t fit.

Can’t wait for what you might have on this issue “Pip.”

Hey mirrorguardian, I don’t know if you’re trying to be cocky with pip but I hope you’re not. Pip’s been on here awhile and although you have a good point, it’s just a point. Let’s wait for cold hard facts before anything, plus pip’s just trying to be helpful.

I’m still sticking with it’s 16lbs, only because I had a discussion with some ford guy once awhile ago, but I talked to another ford guy the other day, and he said and i quote “no idea” LOL

No, I’m not trying to get cocky with him. I’m just waiting, I have alot of patience when it comes to my car.

I saw in a thread in another forum, he’s trying to findout again for me. I just talked about the size because I don’t understand why you would make 2 style injectors if the do the same job.

Of course I’m finding that Ford does alot of stupid things they shouldn’t do.

was there any real modification or tricks done when changing the injectors, or was it a simple swap?

yeah, injector size is all 19 lbs…and with that new MAF, you’ll need to get a chip. the stock computer won’t compensate and you’ll have a/f ratio problems.

Oh, that was awhile ago. I should have deleted this topic, but I’ll give you an update.

You right, if you change out the stock MAF for something bigger, you need to modify the computer signal or must have forced air. The Mustang injectors were plug and play.

The injector swap was simple, though it did take some time. The difference between the Zx2 injectors and the Mustang injectors is that the Mustang injectors can atomize the fuel better. No realized performance difference until you get to 70mph. You know how you hit with what seems like a wall of air, after that wall your speed then creeps up. With these injector, it doesn’t happen.

I know this is some what of a old tread but I think the stock injectors are 16lbs. I went to ZXTuner and use the fuel injector calculator and for the stock HP it recommended a 16lb injector. If thats what recommended for that hp range Ford wouldn’t have put bigger injectors then they needed to (save on MPG and such). Also why would there be a ford racing injector upgrade thats the same lbs as the stock injectors, it dosen’t make sense. Personally I don’t know one way or the other but I tought I’d but my 2 cents in.