Hehehe, check this out, exploding rings
11-14-2003, 03:18 PM
#1
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Hehehe, check this out, exploding rings
We were going to dyno my car with various chips and exhaust, but I had a compression test done first.
4,000 miles ago at 6,560 miles all cylinders were between 2% and 4%, except that number 4 was at 10%.
Now at 70,000 miles, number 2 is at 28%, two others in the 20 percent range and the low is cylinder number 4 still at 10%. My former worst is now my best.
Question: What could cause my rings to crack and disinegrate so quickly. Shop thinks might have been a detonation issue. What do you think.
BTW, the birght side is the guy at my shop is nationally known for his head work. He does custom head and valve work that is supposed to make great improvements on accelleration. They were showing me his work today and what he does. Impressive. My car will be very quick when this is all over with.
4,000 miles ago at 6,560 miles all cylinders were between 2% and 4%, except that number 4 was at 10%.
Now at 70,000 miles, number 2 is at 28%, two others in the 20 percent range and the low is cylinder number 4 still at 10%. My former worst is now my best.
Question: What could cause my rings to crack and disinegrate so quickly. Shop thinks might have been a detonation issue. What do you think.
BTW, the birght side is the guy at my shop is nationally known for his head work. He does custom head and valve work that is supposed to make great improvements on accelleration. They were showing me his work today and what he does. Impressive. My car will be very quick when this is all over with.
11-14-2003, 03:21 PM
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hey doug !!!
they should do a leak-down test with compressed air to check it is the rings .
to answer your question , it could be excess fuel that have washed the bores
they should do a leak-down test with compressed air to check it is the rings .
to answer your question , it could be excess fuel that have washed the bores
11-14-2003, 03:35 PM
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They did leak and compressed air. Air was coming back out through the top hose by the intake. One of the rings is apparently in pieces and some others are cracked. He said he usually doesn't see this type of damage on a normally aspirated engine.
11-14-2003, 03:37 PM
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ouch !!!!!!!!
seen it in the past due to bad storage over winter , but i know this isn't the case .
our cars have 2 knock sensors , better get them checked out !!
seen it in the past due to bad storage over winter , but i know this isn't the case .
our cars have 2 knock sensors , better get them checked out !!
11-14-2003, 03:55 PM
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We talked about those and how it should make necssary adjustments. Seems like I had a quick series of bad detonations at high rpms. I think I felt it. I was in second gear at about 5,500 or so when it happened.
11-14-2003, 10:33 PM
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No more ideas.
Looks like I am be going with a Lenz system 310 or 340 hp. They are going to do alot of internal stuff and this car should be a screamer when it gets done. It will be tough waiting the two or three weeks to get it back though.
Looks like I am be going with a Lenz system 310 or 340 hp. They are going to do alot of internal stuff and this car should be a screamer when it gets done. It will be tough waiting the two or three weeks to get it back though.
11-14-2003, 11:08 PM
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Originally posted by Doug H
No more ideas.
Looks like I am be going with a Lenz system 310 or 340 hp. They are going to do alot of internal stuff and this car should be a screamer when it gets done. It will be tough waiting the two or three weeks to get it back though.
No more ideas.
Looks like I am be going with a Lenz system 310 or 340 hp. They are going to do alot of internal stuff and this car should be a screamer when it gets done. It will be tough waiting the two or three weeks to get it back though.
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11-15-2003, 03:20 AM
#8
Drifting
Broken rings????? That is not normal! Did you had a engine rebuild earlier?
I think some might happen there. Piston rings will brake never by them selfs, somthing happened with too much rpm's or, yes, detonation caused by a wrong chip..............
I think some might happen there. Piston rings will brake never by them selfs, somthing happened with too much rpm's or, yes, detonation caused by a wrong chip..............
11-15-2003, 12:03 PM
#9
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No prior rebuild except in 91 it was torn down, ported, polished and rec. some head work, aluminum intake parts were anaodized and etc. I felt the engine let go at about 5,500 rpms in second gear. It honestly sounded like a decompression or a fart if you will and the power sagged. I was like of no, something bad really happened. I ran another 0 - 60 right after that with no strange sounds, but it did not have the hard pull above 4,500 rpms and was about 8 or 9 10ths of a second off.
Ruairidh:
I will certainly let you know. Mine situation is a bit different as they are tearing the motor down already so they are trying to work the prices together so I don't get charged effectively twice for same labour. Should know by Monday.
Ruairidh:
I will certainly let you know. Mine situation is a bit different as they are tearing the motor down already so they are trying to work the prices together so I don't get charged effectively twice for same labour. Should know by Monday.
