I went to the track yesterday and the best I could do was a 17.0 @ 83 MPH, thats up at 6000 feet though. But the thing is last time I went to the track I ran a 15.5 @ 91 MPH, what gives? I installed my new cam, and it took off 1.5 seconds in my 1/4 time, thats f***ed up! Now the car is mis-firing and needs new plug wires, but that can't be worth 1.5 seconds! Does anyone have any ideas?

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1987 Chevy Camaro IROC-Z
L98 TPI 350 (5.7L)
TH 700R-4 Transmission
Borg Warner 7.75" 9 Bolt Rear End with 2.77:1 Gears.

Current Mods: LT4 HOT Cam, Comp Cams 1.52:1 Roller Rocker Arms, Edelbrock TES 1 5/8" Headers, Hooker 3" Aerochamber Cat-Back System, Performance Resource Chip, Accel Ignition, K&N Filters, JET TPI Air Foil, All Free Mods, Falken ZIEX Z-Rated Tires.

Best ET (w/o LT4 cam): 14.32 @ 97.7mph
(corrected for elevation)

Soon to Come: 7.625" 10 Bolt with 3.42s and Accel TPI Intake Base

 

You've probably already done this but check your ignition timing to make sure it's what it should be. Also, make sure when you put the cam in that you got it's timing right too. If the timing chain was installed improperly (crank not lined up with cam) then that would cause a huge decrease in power. Also, hook up the computer to a scanner to make sure all the sensors are working properly. My car was way down on power from what it had used to be just a while ago. My knock sensor had gone bad and it took me forever to figure out that it had. Once I changed it, the difference was night and day. Don't know what else to tell you. The LT4 hot cam is a little big for a basically stock motor but it shouldn't cause such a huge decrease in power.

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1991 Z28 - 350 TPI, T56, McLeod street clutch, LT4 pressure plate, Pro 5.0 shifter, ported plenum & runners, AFPR, Holley Annihilator ignition box and wires, Hooker shorty headers w/o AIR, Flowmaster muffler, homeade ram-air, SSM subframe connectors, Kenny Brown STB, Global West steering box brace, Steve Spohn adjustable torque arm and T56 crossmember

 

One or two dead cylinders will suck the power right out of you. On top of that, what if the miss isn't being caused by the plug wires and you have some kind of true mechanical/electrical failure. Perhaps your ECM is picking up all that missing as knock and not only are you running on 6 cylinders, you are also running with timing on the back bumper.
Basically (as you should already know w/ 1600+ posts) is that we cannot help you if you are staring at an obvious problem. Fix the miss and then see how it runs. If it's still pig slow we can work from there. But right now, the best guess anybody can give is that your car is broken, and by your own admission it is.
...ed

 

Alright, thanks guys, I am going to buy those plug wires soon and we'll see what that does. I have no codes on the SES light, although I could check with the ALDL and see if any are stored in the ECM. I did find a male end connector inbetween the firewall and engine at the track, but I couldn't find the female end to it. Where is the knock sensor located on the block, is it that one inbetween 6 and 8? Anyway, thanks guys.

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1987 Chevy Camaro IROC-Z
L98 TPI 350 (5.7L)
TH 700R-4 Transmission
Borg Warner 7.75" 9 Bolt Rear End with 2.77:1 Gears.

Current Mods: LT4 HOT Cam, Comp Cams 1.52:1 Roller Rocker Arms, Edelbrock TES 1 5/8" Headers, Hooker 3" Aerochamber Cat-Back System, Performance Resource Chip, Accel Ignition, K&N Filters, JET TPI Air Foil, All Free Mods, Falken ZIEX Z-Rated Tires.

Best ET (w/o LT4 cam): 14.32 @ 97.7mph
(corrected for elevation)

Soon to Come: 7.625" 10 Bolt with 3.42s and Accel TPI Intake Base

 

Yes the knock sensor is between the 6 and 8 cylinders. It is round.

 

The knock sensor is in the block though, not in the cylinder head. The one in the cylinder head is the fan switch. To get to the knock sensor, you'll have to get under the car. Concerning that male connector you found, check to make sure it doesn't plug into the ignition module at the distributor.

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1991 Z28 - 350 TPI, T56, McLeod street clutch, LT4 pressure plate, Pro 5.0 shifter, ported plenum & runners, AFPR, Holley Annihilator ignition box and wires, Hooker shorty headers w/o AIR, Flowmaster muffler, homeade ram-air, SSM subframe connectors, Kenny Brown STB, Global West steering box brace, Steve Spohn adjustable torque arm and T56 crossmember

 

Don't forget to reset the tranny's TV cable, too. A lot of hard driving will knock it out of adjustment. The article's under the tech section...

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-Tom P (Hot rodded 1986 Firebird 2.8l) from http://www.f-body.net/mailbag/3rd/3rd_mailbag.html message boards
---Think your car could be pic of the week? Visit http://www.f-body.net for details!

 

We took a look at the male connector in the back of the motor and my friend and I have concurred it may be the one that plugs into the tranney, maybe a speed sensor or something, although my speedo does work, oh well...

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1987 Chevy Camaro IROC-Z
L98 TPI 350 (5.7L)
TH 700R-4 Transmission
Borg Warner 7.75" 9 Bolt Rear End with 2.77:1 Gears.

Current Mods: LT4 HOT Cam, Comp Cams 1.52:1 Roller Rocker Arms, Edelbrock TES 1 5/8" Headers, Hooker 3" Aerochamber Cat-Back System, Performance Resource Chip, Accel Ignition, K&N Filters, JET TPI Air Foil, All Free Mods, Falken ZIEX Z-Rated Tires.

Best ET (w/o LT4 cam): 14.32 @ 97.7mph
(corrected for elevation)

Soon to Come: 7.625" 10 Bolt with 3.42s and Accel TPI Intake Base

 

That connector might be for your TCC if you think it plugs into the tranny. Is it locking up? Just a thought ~ Arnold

 

The only connector that goes into the tranny is a four pin connector in the shape of a square. It goes in the passenger side/top of the transmission and I doubt this is the same wire you found by your firewall. However I could be wrong...

 

Okay, well thanks guys, you gave me several things to check for. I guess I just need to get under the car and figure it out the hard way. Thanks again!

------------------
1987 Chevy Camaro IROC-Z
L98 TPI 350 (5.7L)
TH 700R-4 Transmission
Borg Warner 7.75" 9 Bolt Rear End with 2.77:1 Gears.

Current Mods: LT4 HOT Cam, Comp Cams 1.52:1 Roller Rocker Arms, Edelbrock TES 1 5/8" Headers, Catco High-Flow Catalytic Converter, Hooker 3" Aerochamber Cat-Back System, Transgo Shift Kit, Performance Resource Chip, Accel Ignition, K&N Filters, JET TPI Air Foil, All Free Mods, Falken ZIEX Z-Rated Tires.

Best ET (w/o LT4 cam): 14.32 @ 97.7mph
(corrected for elevation)

Soon to Come: 7.625" 10 Bolt with 3.42s and Accel TPI Intake Base

 

If the wire and connector are on the drive side of the car near the valve cover (the wire might have a violet color it) it is not used......

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Hank
87'IROC Z28
Hanks 87 IROC

 

Thats exactly where it is, Hank. What is it for and why is it on the wiring harness?

------------------
1987 Chevy Camaro IROC-Z
L98 TPI 350 (5.7L)
TH 700R-4 Transmission
Borg Warner 7.75" 9 Bolt Rear End with 2.77:1 Gears.

Current Mods: LT4 HOT Cam, Comp Cams 1.52:1 Roller Rocker Arms, Edelbrock TES 1 5/8" Headers, Catco High-Flow Catalytic Converter, Hooker 3" Aerochamber Cat-Back System, Transgo Shift Kit, Performance Resource Chip, Accel Ignition, K&N Filters, JET TPI Air Foil, All Free Mods, Falken ZIEX Z-Rated Tires.

Best ET (w/o LT4 cam): 14.32 @ 97.7mph
(corrected for elevation)

Soon to Come: 7.625" 10 Bolt with 3.42s and Accel TPI Intake Base

 

Yes, actually, it can.



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"Question with boldness even the existence of a God; because, if there be one, he must more approve of the homage of reason, than that of blind-folded fear."

-Thomas Jefferson