how to swap out injectors

[zvir]

Hello everyone, my name is Oleg and I resintly bought my first bimmer. I'ts a 97 328i, stick, and very fast in my opinion. My Q? is:
I bought an M3 air mas flow sensor, intake manifold and injectors, the manifold and sensor I should have no problem instoling, but since it's my first upgrade, I'm nervice about the injectors, taking the fuel rail of and puting it back on wright, I dont want my car to blow up while I'm driving because of a gas leek. Any adwise will be grately apressiated. Thanx

[Wayne 962]

Hi there. I have a tech article coming on this - maybe I'll be able to finish it tonite - it's on my short list of ones to do...

Stay tuned...

-Wayne

[Wayne 962]

Here's a preview:

http://www.pelicanparts.com/bmw/techarticles/E36-Injector-Replacement/E36-Injector-Replacement.htm

-Wayne

[zvir]

Thank you, can't wait, I should get my car back from the shop just in time.

PS: Do you by eny chance know the hp increase from these mods.

[Wayne 962]

You're not going to get any increase in performance from injectors. The only reason you would want better flowing injectors is if you increased the displacement or placed some type of turbo or supercharger on your engine. The Motronic system does a very good job of suppying just the right amount of fuel - too much, and the car will run rich, which will decrease power and efficiency.

What is it exactly that you are looking to do?

-Wayne

[Jared at Pelican Parts]

I think he is talking about upgrading to a larger AFM and larger injectors. It does give you a very slight increase in power, provided you tweak the CO mixture. (Not something you want to do unless you have a meter and want to pass smog) Gains on a stock motor would be maybe 1-3HP, if that.

I did it on my car to accomodate my headers, which gave me a slight flat spot in the upper RPM range. Car was running too lean due to the scavenging effect of the headers. A bigger AFM (off a 535i) and injectors (off a Mustang 5.0) fixed it.

Wayne is right, though, you really dont need to do unless you have turbos, larger displacement pistons, etc... In my case it was somewhat overkill.

[Wayne 962]

Originally posted by Jared at Pelican Parts
Car was running too lean due to the scavenging effect of the headers.

I'm not sure if that's correct. The only way you'd have your exhaust affecting your mixture like that, is if you upgraded to a much hotter camshaft. I don't think there's enough overlap in the Motronic cams to allow the headers to make much difference. Did you monitor the A/F ratio while driving? There's a new tool available (we're going to be carrying it) that does this for you...

-Wayne

[Jared at Pelican Parts]

yup, was monitoring the A/F mixture while doing it. Headers almost always lean out the mixture of any car.

C/O at idle was like 1.7% without the headers, went down to like 0.45% once installed. I just installed the larger equipment and took it back up to 1.7% Car runs great.