jbird

Ok guys, today I ran a 15.96, a 16.15, and another 15.96. The car is a '95 formula 'vert w/ 98k miles. It has a k&n filter, a flowmaster muffler (not a complete cat back), a tbb, a 1LE elbow and a mild tune by CSS in myrtle beach. This was at Pittsburg Raceway in PA.


R/T....redlight.........597.........501
60'.....2.234...........2.465.......2.251
330....6.521...........6.750.......6.588
1/8....10.124..........10.339.....10.182
MPH...68.04............68.28......68.40
1000..13.272..........13.476.....13.312
1/4....15.961..........16.156.....15.962
MPH...83.58............83.82.......86.48

Ok, now for a little background. Back in about June of last year the car ran a 9.23 in the 1/8 in South Carolina, but I don't have a MPH or anything for that run. Then it had a bad distributor and was missing pretty heavily, plus a torn intake elbow and a bunch of other vacuum leaks, like around the throttle plate and stuff.

I put a 1LE elbow on and have been through several distributors since then, as well as a computer and a few ICM's and coils. The current distributor was put in in december, as well as the ICM and computer. Today I put a K&N filter in the car, but not a complete CAI.

It doesn't seem like it's missing or anything, it pulls smooth through the revs. A couple of weeks ago my cat was rattling and now the noise has quit, so I don't know if it could be plugged or what. The tune went in as well a couple of weeks ago, but the car felt much stronger afterward. The tranny or converter could be slipping a little I guess, I dunno, but it shifts nice and firm and there's no slipping like a toasted clutch on a manual car or anything.

Does anyone have any advice?? Thanks in advance. J.Bird

30th TA 0219

check out that cat issue!
And make sure oyu don't 2 plug wires dangling LOL That's really off from where it should be, unless you're running at like 6000'+

buzz12586

Your MPH is 10-15mph off. There has to be something majorly wrong that I think you would be able to notice.

jbird

I know!! It's way low, I got eaten alive by a V6 accord. I don't know what's wrong with it, but I don't really notice anything. Granted elevation at the track is like 1500 ft. or something, but still, it's waay slow.

jbird

It runs normally, no miss or hesitation or anything, it just doesn't pull very fast. It isn't missing or backfiring or anything, and I don't really know what to do with it. You guys have any ideas as to where to start? I checked the plug wires, and they're all on good. I don't really have anywhere to do anything major to the car, and don't have the money to take it anywhere, so I'm not sure what to do with it.

sleeperMULLET

hey man, I was the one with the Green Z28. If you think there is something wrong with the cat, give it a bang and listen for a rattle, if the cat broke up it could be sliding back into the exhaust causing a restriction. Also, when I talked to you, you had mentioned that your replaced the plugs alot, what did they look liek when you took them out? That tune might be causing you to run extremely rich, do you get bad gas mileage?

My car ran pretty good today, 2.1 60 foot, 13.4 1/4 at 103mph. I was still spinning all through first though, I quess the track was still cold.

jbird

Hey, glad to hear you ran well. I'll go smack the cat in a minute. The plugs all looked good when I changed them, except of course the factory plugs had about half of the little platinum pucks missing. When the car cools back off a little I'll probably go look for burned wires and such. My milage seems to be about the same, but before the tune the car ran pig rich, which has mostly cleared up. Thanks for the advice. I'll post up what I find.

kick Z tail out

There is a big time problem. Your car is 2 seconds slower than it should be... And 2 seconds in the 1/4 is an eternity.

jbird

Ok guys, I sniffed around the car for a while and this is what I've got so far. I don't know if it's enough to cause the car to be that much slower or not, but as I was checking all the wires the boot on the very rear driver side plug was very easy to turn. I pulled the wire off and took the plug out with my two fingers. The plug itself looks good, the porcelain surrounding the electrode is a really mild tan/off white color. I'm thinking the plug may not have been grounding good w/the head and I was down a cylinder...Sound Feasible???

I banged around on the cat and didn't really get any rattling, but the exhaust was rattling in the cat area before break from school, approximately three weeks ago.

ddj19852003

I would go ahead and replace the cat, I had a little rattle in mine and I just ignored it and it seemed as it went away then one night my car could barely make it up the hill to get to my house the crawled up the hill @ like 10 mph and I was flooring it. Once I got home I popped my hood and my exhaust manifolds were glowing red, I had a horribly clogged cat.

jbird

I may try to gut it within the next few days or something. Is there any visible way to tell a clogged cat besides glowing exhaust manifolds/and or cat?

johnny3986

I believe you want your plugs to be tan...At least on ATV's you do and I am about 90% sure it goes for car.

If they are black BLACK....it means you are running rich..

White plugs (like SUPER white means you are lean)

Tan is middle ground and means stoich I believe

Silvershark

Check to see if you have any plug wires burnt. Last year I was trapping 98mph and 14.4 runs with LE2 heads and GM847 cam, with a custom tune. Melted or even burnt spark plug wires can make a HUGE difference. I had to actually take my spark plug wires off individually in order to find the problem due to the fact where the burn marks were. I replaced the plug wires and it pulls like a raped ape now.

Z28LT1_Just_Nasty

My Camaro had a serious loss of power when the cat clogged, also caused my car to overheat and blew some seals. Have that checked out right away. Check you plugs and wires, cap and rotor, change your air filter those kinds of things.

FastZinTennessee

High flow cat if you are worried about emmissions or straight pipe if not.

In my experience if the wires are going bad you will get a noticeable stumble that gets worse with load and engine speed.

Your MPG would be good to know. Slight tan on the plug electrodes generally indicates the motor is running fine as far as air/fuel ratio is concerned.