PMC_93LT1

Hello all, first post on the site, was reccomended by a friend. I have a 93 Z28 LT1 and I am working on it here and there. The only real modification so far is the K&N intake. I have also done the norms like oil change and trans service since I just got the car a couple weeks ago and want to get everything done that I am not sure if it has been done in, well, forever. I have a new set of plugs and MSD wires that I will be installing soon. I also purchased from someone I know a set of 24# injectors. The person used them for a little bit in a slightly newer LT1 so I got a good price. They have not been used very long and he just added bigger injectors. They are Bosch/Ford injectors 0 280 150 947 / f1te-d5a. Question is, I was told they are pretty simple installation just unbolt the fuel rails, replace and put back together adding some dielectric grease when I install them. Will I need to change anything else around as far as the computer or will it just pick up the better fuel and keep going? I do also plan to have the car tuned soon, waiting for I think 1 more person to sign up for having it done by a guy who has been doing it a long time. He will travel if he gets enough people who want it done and we are close. Thank you in advance, I am anxious to install them lol.

Injuneer

The stock injectors in your 93 are 22 #/HR (although the constant in the ECM is a bit higher). The Ford injectors, are flow rated at a lower pressure, to they will flow about 25.3 #/HR with your stock fuel pressure. That means you are flowing up to 15% more fuel for any given injector pulse width, and the ECM will have to use the full capability of the long term fuel corrections to reduce the excess fuel flow. And when you go WOT, the ECM will default to 0% long term corrections, and the engine will run excessivley rich.

How many miles on your 93? Do you have any indication there are problems with the stock injectors? If not, there is absolutely no reason to change them. The ECM won't pick up the "better fuel"..... it will pick up the excess fuel flow from the oversize injectors, unless you have a new chip burned for the higher flow constant. Probably best to wait until you get the new chip to put in the injectors.

You just need to pull up the rails, as you indicated. But you will either have to disconnect the fuel hard lines, or insure there are no brackets preventing you from lifting the rails without disconnecting the hard lines. I know in the 94+ there is a bracket to be released, but the 93 hard lines/rails are different that all other years, and I don't know the details of how the hard lines are retained. You should also bleed off the fuel pressure, and have a can ready to catch the spill when you remove the first injector.

Move the spring clip on the harness connector to the release position on each injector, and remove the harness connectors. Since your 93 is "batch fire", it isn't necessary to keep track of which harness clip goes on which injector.... another area where the 93 is different that all other years.

You need to blow any dirt out of the holes for the injectors before you pull the rails up. After removing the 4 bolts that hold the rails to the manifold, it may be hard to break the injectors loose from the manifold. I found it best to stand on one side of the engine, and reach across to the other side of the rails and pull up, popping the 4 injectors on the other side out of the holes. Some people report having to use a lever to pry the rails up.... if you do anything like that, make sure you don't damage anything. Make sure the O-rings came out of the holes with the injectors. If they didn't, you have to fish them out.

Then slide the retainer clips off to one side on the rails (again, I'm assuming the 93 is the same as the 94+) so you can pull the injectors out of the rails. Again, make sure you have the O-rings on the injectors.

Reverse the procedure to reassemble. Make sure the injectors have good O-rings on both ends. Use a light oil or grease on the O-rings to prevent them from tearing.

PMC_93LT1

I am setting right about 146K on the odometer. I have a lot of plans for the car in the future and it was supposed to be a cheap option to get a little more hp from the engine, and since I plan on having it tuned within the next month (I hope) I figured it would be something easy to do for the moment to keep me busy. I was also told the original injectors were only 19# and kind of sucked which is another reason I bought them. I guess I should have talked to someone here before I went out and started spending money on new stuff. I am completely new to the camaro but I got a good deal on it and wanted something with more options than the other toys I bought before. I have considered 383 stroker, a supercharger or remote turbo, definately full exhaust header back, I like the idea of the LT4 top end. I know I will have to rebuild the engine before I start going that deep which is why I am looking at minor mods to do for now until i figure out which route I am definately going to take. I am also considering or looking at 3.73 gears for the rear end. I have new tires so it is a little harder to just set and smoke them now, which is good and bad at the same time lol. Anyway, I appreciate all the info and to answer your question, no I do not know of any fault in the current injector other than they were supposed to be inneficient in 93 and have a bad spray pattern. But like I said, this is my first camaro, and my other "fast car" was carbed so there is a lot more to know about FI and I still have a lot to learn.

Injuneer

There is nothing wrong with the 93 injectors. I have never heard of them being inefficient, or having a bad spray pattern. The GM Rochester injectors have an excellent pattern and atomization, that is their strong point. The manifold location was chosen based on those injectors.

PMC_93LT1

Thanks again for the information. I guess now I have to see if I can get the money back out of the injectors which should not be too hard with the price I payed for them. Thanks again and I will be sure to do some more research before I start going any deeper than the plugs and wires for now, well and the gears lol.