So, my car is a 1994 Z28 with a pretty much bone stock LT1 (with 174k miles), and it's damn slow.

I put up a thread regarding this same problem something like 4 months ago, but I never actually got the chance to go out and see if my car's problem was fixed. Well, I found out that it's still running far, far too slowly. Like, 0-60 in 10+ seconds slow. (I did a comparison with my brother's V6 Chevy Tracker. Scroll to the bottom for the results.)

It's not so much that the car isn't fast (top-speed), but it feels extremely lacking in all terms of acceleration. I mean, I'm going down the road at 40-45mph, and I have to floor it just to pass somebody; the engine starts screaming (like it should) but all with hardly any power, and it still takes me a good amount of time to pass the other driver. Anyway, I'm hoping it's not the entire engine that's plain ol' bad and that it's just a part or two I can replace, but I don't know where to start. That's why I'm here. It might even be something purposeful that one of the previous owners did that I don't know about, but I need suggestions (don't keep quiet about "obvious" things you think I probably already know; I really know hardly anything about this car).

EDIT: Something I missed, though I'm not sure if it's relevant. I got my car used, and one of the previous owners lowered the car. The tires also spin very easily if I give it a little extra gas when leaving a light or parking lot, though I'm not entirely sure if that has anything to do with the car being lowered; I don't know a lot about the vehicle and am not that close to being mechanically inclined. I don't know what they did to lower the car besides that they didn't just cut the stock springs. Here are a couple images if that helps:

(Ignore the SS stickers on the sides; I plan to get rid of those soon enough and replace them with the non-poser Z28 ones.)
http://s1302.photobucket.com/user/gu...ml?sort=3&o=14
http://s1302.photobucket.com/user/gu...ml?sort=3&o=10

I make videos/movies as a hobby (I'm going into film school), so I thought I'd grab my phone just to get a little bit of footage for demonstrating. First off, I don't know if the car revs slower than it's supposed to or if my problem lies somewhere else, so I grabbed a quick video of that -- every time I hit the pedal in the video, I'm flooring it, keep that in mind. You can tell me if it looks and/or sounds normal.

[autostream]http://autostream.com/camaroz28/?page_type=firebirdplayerthumbnail&framepage=2816& transactionid=1383018874-7150752&posted_by=gunmetalTrevan_www.camaroz28.com &youtube_video_id=Yl6bgQtRfF0[/autostream]

Then I compared my car's performance to my brother's V6 Tracker. Here are the tests I ran and the results:

--0-60mph--
Tracker: 10.2 seconds
Camaro: 9.8 seconds

--45-60mph--
Tracker: 5.4 seconds
Camaro: 6 seconds

If you're curious, here's the video I slapped together for those tests:
Something's Funny With My Car - YouTube

If I can be pointed in some sort of direction, that would be great. The only reason I'm here is because I have no idea where to start with an engine like this, so some ideas and thoughts would be greatly appreciated.

Thanks.

 

I heard a little clicking up front. Common issues that could cause loss of power and clicking/knocking are: leaking exhaust manifold gasket, arcing optispark, flat lifter, and the classic rod knock.

Check for black soot all around the manifolds with a bright light. Especially the passenger side toward the rear. they always go there.

Then at night inspect for any spark arcing light show that could cause loss of ignition power.

Use a stethoscope to listen for tick/knock and probe rocker arm studs and oil pan. The rocker arm studs are under the valve covers. Without a steth, you can use a screw driver up to your ear as a trick.

 

If it's a 6 speed, clutch could be slipping.

 

If it's a 6-speed, what gear are you in when you try and pass another car?

Have you scanned it for codes. If it's an automatic, there are transmission codes that don't turn on the SES light. Have you checked the fuel pressure?

Have you checked basic components like the air filter? Do you still have a catalytic converter? If so, have you had the back-pressure checked to determine if the cat is plugged?

 

My cat has been gutted (I live outside of the smog region), and it's an automatic. The check engine light came on and off a few times when my cat was falling apart, but since I had a friend (whom is a mechanic) gut it, I haven't gotten anything. A few months ago, it kept randomly dying down the road, so I took it to a repair shop (turns out my distributor was basically dead, so they replaced it; the car has been running fine since), and while searching for the problem they scanned it and told me it wasn't throwing any codes.

I believe my father had a new air filter put in, but I'm not 100% sure. I can take another look later today. I also haven't checked the fuel pressure, but, again, I can do that later today.

 

John, are you sure the clicking you heard wasn't just the exhaust popping? I keep listening for it in the video but I don't hear it...

I forgot to mention that I had my distributor and water filter replaced a few months ago, so would that mean I don't have to worry about any sort of optispark problem? :s

Also... I've got some news. I'm not sure if it's relevant to my problem, but at least it's something I've found. So, my air filter... Turns out I most certainly did not have a new one. In fact, it looks as if (bare with me since it's likely I don't know what I'm talking about) one of the previous owners got a cold air intake and just ghetto replaced the air filter when the time came. I pulled off the elbow and saw this:

 

There's you're problem possibly. Look at the available surface area of the filter. I would replace for sure with a stock one if possible. Test it with the air filter disconnected(short test around the block).

Oh yeah and I do hear a click/tap/knock sound that is not the exhaust popping. It is hard to hear because of the exhaust, but something is a little off. I analyze audio tracks all the time and I have an ability to separate overlayed noises in my head. I would expect at 174k, a few issues like that anyways. In the vid it was pronounced about 3/4 through(53-54 second mark is obvious).
The computer will retard your timing when it detects a knock/tap. This will make it loose a lot of power, so it is possible. Use a screwdriver held up to your ear, and place it over the valve covers, and then over the oil pan. Get someone to play with the throttle like you were while you listen.

Also check for those exhaust leaks at the back of the manifold. Injuneer also mentioned this! Any leak will cause nasty issues, and guess what all Camaros I've seen leak on the passenger side toward the rear #8 cylinder.
Get a bright light, otherwise you aint seein nothing. Don't be shy to get underneath the car and look up too.

These checks are easy and can be done with eyes, ears, and hands.

 

Alright. When I do a test without the filter, should I remove only the filter and not the intake and sensors? Because it looked like it was taped on the elbow and I don't know if it will be so easy getting it back on unless I just take off the whole thing.

I wasn't able to do anything beyond the air filter because I ran out of time, but I went ahead and tried the screw driver trick on the block itself to see what would happen, and I did hear a very faint knocking sound. I'm really hoping there's no rod knock in the car...

I'll get under it, too, it's just so low to the ground that a friend of mine actually had trouble setting up the jack (plus the ground effects got in the way, and he didn't want to bend or break them).

If that is the case, though, would it cost a lot to just do an LS1 swap? How about insurance rates vs. the LT1?

 

Right just remove the air filter box, and make sure there are no leaves etc to suck up during test.

A faint knock may be nothing to worry about, usually it is pretty distinct up close like that with a tool or stethoscope.

Jacking it up is a pain sometimes, I hear ya. With a bright light, you are checking for black soot around the manifold. That would explain loss of power and noise.

But that filter really looks like it is killing your power. Sounds like it too, almost like a clogged cat, but instead the clog is upstream in the air filtration.

I personally would swap with another lt1, if that ends up being the worse case scenario. The cost can go up for lsx swap.

 

Has the car always been like this ???? look on.the driver side door and see what gears
the car came with .... SORRY .....gear codes found in glovebox......

 

My car has been basically out of gas for the past couple of days, so I haven't been driving it -- I won't be able to dive it for a few days further, either.

Something new happened this morning, though. So, normally when I go out to start my car in the morning, it almost seems like it's having trouble (sounds like the battery is low), but it still manages to get started up with a relatively small amount of effort. Today, though, after not driving it for a few days due to said event, the battery was too dead for the car to start. During the summer, I went out to my step-grandpa's house, and he had a tool to measure how much the battery was being charged while the car was running and the levels of the battery when the car was off. They were a bit low, but they were still in the "normal" range on the tool. Is this just a failing battery or could there be something else I'm looking at?

Also, this car has a history of having the battery be dead on me. Mind you, the problems were my fault, but only because the car seems to be sensitive with this kind of thing. By that, I mean one time I left my iPod on in the USB port (no A/C or anything else) and went inside my house to grab something but ended up talking with a friend and staying there for about an hour. When I remembered and ran out to my car, it was completely dead. No beeps with the door opening or anything. I understand that charging a device can draw out more power than just the radio, but the charging rate is so low that it would take hours to charge my iPod in the first place. Another time, I did leave just the radio on (no iPod and, again, no A/C) for three hours (due to a shockingly similar event -- I'm pretty absent-minded and that has proved to cause problems), and same thing; DEAD, dead.

In other news, though, I took a quick look at my car at night (it's when I get off work and really the only time I can look at it on certain days :/ ), and I did happen to find one very small hole (maybe a couple toothpicks could fit in it) in the exhaust, but it's near the back. I left the car running and listened for any strange sounds, and I heard exhaust puffing out that was louder when I was next to the rear weel than when I was actually behind the car. Sure enough, there was a little poke in the pipe with a small radius of black around it. If there's one there, there might be a few more further up, so I'll have to check that out later.

I still haven't tried the car without the air filter yet, but I'll try to get on that within the next few days.

Also, I haven't checked the driver side door, either. I can do that when I get home today.

 

Something may be causing the battery to drain even when the key is off. You need to run an amp meter in series with the battery cable, to see what the current flow is with the key off. If there is a significant flow, start pulling fuses to see which circuit is causing the problem. You say you have a USB port, and since none of the 94's came with that stock, I assume there has been some wiring changes to the vehicle.

 

Alright, I'll have to look into the wiring a little bit. My stepdad took a quick look at the CD player and face (he's in the Army now and can't help much further unfortunately), and he thought it was directly wired into the battery to where it would stay on even when the car is off, but it doesn't. There's probably something small, but it's not much of a concern at the moment.

Right now, I'm wondering about my exhaust. Before I got the cat removed, it didn't sound as beastly as it does now, but now it almost sounds... dirty. I don't know, after listening to it in that video it just sounds clanky or something. Also, there were exhaust pops when I had the cat, but now they're much more frequent when I rev it and they sound ugly -- like a piercing or shrieking pop as opposed to a deep or powerful yet softer pop. Would a resonator do anything, or is that another symptom of an exhaust leak?

 

Sorry dude, this is kind of a late reply but to be honest, a few small holes near the back of your exhaust (not sure whether you meant they were by the muffler or near the block) wouldn't affect the car that much. Either way, you would only lose small, small gains over that. (You probably wouldn't even notice in fact).

Did you ever end up checking the air flow problem through the filter? Or did you manage to get it fixed altogether?

 

Neither of those is the Service Parts Identification label. Look in the glove box for something that looks like this (this is not an F-Body label - it is just a picture I found on the 'net):

http://i53.photobucket.com/albums/g5...S/IMG_2531.jpg