1993 camaro z28 project thread

[9302z28SS]

Picked up an ls1 lid from TRY MEH. Thanks

[9302z28SS]

ls1 lid slp

2013051495161201.jpg

[meissen]

Awesome - looks like you have the lid all hooked up

[9302z28SS]

Yup i do. It breathes so much better now. Ive got a k&n filter
Too.

[hoogiesngrinderz]

Careful, K&N filters can mess up a MAF sensor in a hurry.

[BP_Z28]

No need for a K&N really.

Sent from my DROID4 using Tapatalk 2

[9302z28SS]

I have a 1993 guys no maf, speed density. Im one of the lucky ones.

Cause i dont need a speed density tune to elminate the maf

[Fox Slaughter]

You don't need a speed density tune on anything to eliminate the MAF.
If you unplug the MAF it automatically goes into speed density.
Or like you said tune, it literally takes one click to eliminate the MAF.

[9302z28SS]

Didn't know that. Wonder if I could add a Maf to my car? Lol I don't know why I would want to though. Lol

[Fox Slaughter]

I'm sure you could but there is no need for it.
Speed density is fine.
I ran last year a speed density, open loop tune.

[meissen]

Is there even a plug for the MAF in your harness? I think there's more to it than just plugging a MAF in, if there's even a plug the PCM likely doesn't have the tables necessary to even do the fuel mappings based on air flow.


That said, since you DO have speed density you might want to watch your plugs and O2s. In my personal opinion, speed density inherently SUCKS because it doesn't know how much air is actually flowing into the engine and thus it's just "guessing" how much fuel to dump into the cylinders for combustion. Basically whether your car runs lean or rich is 100% dependent on how well your o2 sensors are working -- if they're all gunked up and not reading accurately you could potentially be running too rich or lean and your PCM wouldn't even know it.

Now - the reason why I bring that up is that you just changed to a lid setup which is supposed to allow for much better "inhaling" for the engine. Meaning right now your engine could be getting more air and the PCM still thinks it's getting the stock airflow, in other words until the o2s kick in you're running lean. That's the inherent bad part about speed density -- any change which could affect how much fuel is actually needed for combustion could require a new tune...

This is how I understand it all, at least - someone please correct me if I'm wrong. I always understood even switching to a cold air intake that a new tune calibration would be recommended and I think in this case the LS1 lid is supposed to flow even better than the typical LT1 cold air intake.

[9302z28SS]

Good point brian. But it wont remain untuned for long.
Once its cammed with longtubes and all the other goodies i have in mind
For it i wont have to worry. Im going wideband o2 with my
Car also i just have to get the o2s and pigtails from another
GM vehicle.

But if i switch to wide band will my pcm still throw a
SES light if one of my o2s are bad?

[9302z28SS]

But also no my car doesnt have a plug in for a maf in the harness. Sorry failed to answer that in the last posting

[hoogiesngrinderz]

I'm a little confused by "i just have to get the o2s and pigtails from another GM vehicle"

Your PCM cannot use the 0-5v wideband. You will need to keep the narrow band (stock o2) sensors and add a bung for the wideband or find one that has a simulated narror band ouput so you can use it in one of the stock locations. Some people have issues with that type of setup though, so keep that in mind.

[Fox Slaughter]

First yes you would have to get a 94+ harness and PCM or wire in the connector yourself for a 94+ PCM to run MAF.
Speed density uses coolant temp, air temp, throttle position, ect and then goes to the SD tables and ads fuel to it. The o2s will tell how much air is in it obviously and adjust fuel also. Using the MAP sensor it can tell the pressure in the intake manifold. Which air in a certain area at a certain temp has a certain density to it.

MAF works by heating up an element to a certain temp, as the air rushes by it cools down the element. The PCM then heats it back to where it wants it and how much voltage it takes to get there tells it how much air is flowing in.