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help, down 7mph and .3-4tenths :(

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Old Aug 22, 2004 | 09:24 AM
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Default help, down 7mph/.3-4tenths (pics added)(problem found)

looking for ideas... going to do a compressin test today and check the plugs, although there are no error codes and my logs look good from the track. hoping its just the valve springs, but kinda doubt it.

the last couple weeks my car has also been falling on it's face launching and running really inconsistant. it's been boggin bad, and I just don't think it should do that with my assload of TQ and at grudge night track prep. been running 123 consistantly which is down from 126-127 till last night when it was running 120 @ 11.12-4. should have been running low 10.80's @ 125-126 in that weather :thumbdown:

have all forged internals, comp R lifters, yella terra rockers, comp 987 springs and cam is 236/232 .602/.575 112.

Last edited by 383ss; Aug 24, 2004 at 09:27 PM.
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Old Aug 22, 2004 | 11:56 AM
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compression check came back with 205-216 in all cylinders.

also add, the engine sounds fine. pulled drivers side valve cover, everything looks ok. was getting about 1 degree knock last night at the track, didn't think it was a big deal.

plugs are brown, no white, and definatly not wet

Last edited by 383ss; Aug 22, 2004 at 12:16 PM.
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Old Aug 22, 2004 | 12:19 PM
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Did you just do a FAST intake swap. Could there be vac leaks or some other issue with the intake throwing the tune off?

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Old Aug 22, 2004 | 01:08 PM
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did a fast intake about 4 months ago and ran a best 10.75 with it... I can look to see if something is cracked or loose.
O2's were running 950ish between both sides, so A/F shouldn't be an issue.
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Old Aug 22, 2004 | 01:22 PM
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How did your 1/8th mile ET/MPH look on those runs? Were they down proportionally as well?
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Old Aug 22, 2004 | 01:22 PM
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found a plug wire that is slightly burned, enough to crack it though. Its not burned into the wire at all.... wouldn't that cause a missfire or some code if it was the problem??
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Old Aug 22, 2004 | 01:23 PM
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Originally Posted by KingCrapBox
How did your 1/8th mile ET/MPH look on those runs? Were they down proportionally as well?
yes, they were.

1.54 60'
1/8 7.126@95.78
1/4 11.14@120.14

normally run LOW 1.5X's sometimes high 1.4's and 6.8-6.9 @100-101 1/8
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Old Aug 22, 2004 | 01:35 PM
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Originally Posted by 383ss
found a plug wire that is slightly burned, enough to crack it though. Its not burned into the wire at all.... wouldn't that cause a missfire or some code if it was the problem??
That might be the source. You can also try starting the car and then pull that spark plug wire and see if anything changes. You might only be running on 7 cylinders.
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Old Aug 22, 2004 | 04:48 PM
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Originally Posted by 383ss
yes, they were.

1.54 60'
1/8 7.126@95.78
1/4 11.14@120.14

normally run LOW 1.5X's sometimes high 1.4's and 6.8-6.9 @100-101 1/8
what is that telling you??
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Old Aug 22, 2004 | 04:51 PM
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Originally Posted by 383ss
what is that telling you??
Sounds like a tough problem to diagnose of the internet. If you're not throwing any SES/CEL codes, try to get it onto a dyno and see if you're power is dropping off earlier than usual.

Other than that try to get the car back out to the track and see if the other night just wasn't a fluke.
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Old Aug 22, 2004 | 06:07 PM
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well, bad news... went to change the oil and see what was on the drain plug. 1st noticed my 02 sensor extension was melted to the header but didn't think that could be the problem. there were 5 chunks of metal on the drain plug. pretty small. flat on one side and curved on the other and the whole peice is curved.

the big ones are .22" long and .25" wide looks like all together, they would form a circle.
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Old Aug 22, 2004 | 06:55 PM
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def post the pics of the metal - i fear it could be a bearing or piece of one. you havent been hitting the nitrous lately have ya? lol. pieces of the ring could have grown tired of the piston. good luck bro.

btw, a dead O2 sensor that was melted up against the header could DEFINATELY have been the reason you are loosing mph and tq. i had the same thing when i had my sensors go out. struggled a full summer till i figured it out. my mph was all over the place too. felt like night and day.
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Old Aug 22, 2004 | 07:07 PM
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Originally Posted by gator's 99TA
def post the pics of the metal - i fear it could be a bearing or piece of one. you havent been hitting the nitrous lately have ya? lol. pieces of the ring could have grown tired of the piston. good luck bro.

btw, a dead O2 sensor that was melted up against the header could DEFINATELY have been the reason you are loosing mph and tq. i had the same thing when i had my sensors go out. struggled a full summer till i figured it out. my mph was all over the place too. felt like night and day.

the peices are definatly from two different things... NO noise from the motor though ???

wish it was the O2's
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Old Aug 22, 2004 | 07:23 PM
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pull the valve covers. check the rockers if they are stock. rocker bearings have been known to eat itself alive.
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Old Aug 22, 2004 | 07:55 PM
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I've had stock rockers go bad before... it isn't those bearings have them all off now, working on the oil pan, not sure how to get it off, lol. it's loose but hitting the bellhousing ??? do I have to drop the k-member or tranny???
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Old Aug 22, 2004 | 08:58 PM
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You don't have to drop the K-member to get the oil pan off but I would makes life a lot easier. I just went through a similar thing man I feel your pain
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Old Aug 22, 2004 | 09:06 PM
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how do you get it out then??? drop the tranny and bellhousing??


heads are off!! everything looks fine in there...
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Old Aug 22, 2004 | 10:04 PM
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It ******* sucks we did it on my friends 98 t/a you can drop the pan about 1-2 inches. Then you get stuck on the crossmember and pickup tube. There's 2 (maybe 4 don't remember) bolts on the pickup tube unbolt those and you can slide the pan off. Getting it back on is even worse.

If it was my decision on what to do I'd say **** it and pull the motor.
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Old Aug 22, 2004 | 10:35 PM
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ya, looking like its time to pull it

here's some pics of the pieces...







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Old Aug 22, 2004 | 10:49 PM
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just my thoughts. you had a cam bolt that was too loose or wasnt properly tq'ed. then the cam "walked" and broke off a piece of the cam bearing. it got loose and you lost your oil volume flow (note you can have pressure yet very low volume). that in turn allowed the motor to eat itself. so you have a piece of cam bearing and main bearing. just my .02 but it makes sense...unfortunately.
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