Very scary compression numbers on my turbo car
#1
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Very scary compression numbers on my turbo car
1-4:
60, 60, 120, 120
I'm guessing the compression gauge is not sealing properly (rubber hose) becuase the car drives the same way it did when it was new. There is no smoke, no blow-by, and it sounds fine. It idles fine, cold starts and warms up fine, and drives fine. Should I be worried? I'm getting a different compression tester tomorrow and getting a working leak-down gauge tomorrow, but I can't sleep with this kind of drama no matter how much I drink.
60, 60, 120, 120
I'm guessing the compression gauge is not sealing properly (rubber hose) becuase the car drives the same way it did when it was new. There is no smoke, no blow-by, and it sounds fine. It idles fine, cold starts and warms up fine, and drives fine. Should I be worried? I'm getting a different compression tester tomorrow and getting a working leak-down gauge tomorrow, but I can't sleep with this kind of drama no matter how much I drink.
#9
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Why would it be consistently wrong? I'm thinking 1/8 turn int he tester fitting either way would make some variation in compression.
Also, do you guys think 243whp at 11psi on 8.6:1 compression is low? I sure do. I'm guessing this motor was blown up a long time ago. I'm really worried about getting in there and seeing a ton of detonation and a dead motor. I guess I'm going to plan on not running TT next year, time to buy a kart.
Edit:
The plugs all look exactly the same too.
Also, do you guys think 243whp at 11psi on 8.6:1 compression is low? I sure do. I'm guessing this motor was blown up a long time ago. I'm really worried about getting in there and seeing a ton of detonation and a dead motor. I guess I'm going to plan on not running TT next year, time to buy a kart.
Edit:
The plugs all look exactly the same too.
Last edited by hustler; 10-02-2011 at 01:11 PM.
#12
i wanna falcon punch you right about now! your cars are broken but they run great. you make alot of sense. I'm this - close to unfriending you for sounding like a clueless chick. you know your in the lead of unlimited class right?
btw - my car made 230whp at 11psi so no, that doesn't sound low
btw - my car made 230whp at 11psi so no, that doesn't sound low
#13
I had a BP that gave me low compression numbers but ran great (85,80,120,80) and by great I mean drove 1200 miles with 3 people and a motor in the hatch. turns out after tearing down the motor the head was cracked in 2 places.
BP's are built like tanks for the most part, they dont die till you ventilate the block.
BP's are built like tanks for the most part, they dont die till you ventilate the block.
#15
I had a BP that gave me low compression numbers but ran great (85,80,120,80) and by great I mean drove 1200 miles with 3 people and a motor in the hatch. turns out after tearing down the motor the head was cracked in 2 places.
BP's are built like tanks for the most part, they dont die till you ventilate the block.
BP's are built like tanks for the most part, they dont die till you ventilate the block.
#17
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Ok, so got a new gauge from HF and new leak tester and things are not good
Compression
60, 90, 120, 120
Leak
60, 60, 40, 10
I can hear air through the exhaust on every one. I've never really over-revved the car so I'm guessing some exhaust valves are burnt. However what really gets me is that the car drives totally fine, and still goes fast as ****. I guess I'm going to run TXMC then take the head off and have a look. If the valves are burnt we're switching to Inco exhaust valves with Berrylium seats. This is weird. Just to be sure I was at TDC I rotated the engine from -5* to +5* to make sure the exhaust valves were closed and never saw a real change in the leak gauge. I'm guessing it's not the tester hose since I always heard air through the exhaust.
Compression
60, 90, 120, 120
Leak
60, 60, 40, 10
I can hear air through the exhaust on every one. I've never really over-revved the car so I'm guessing some exhaust valves are burnt. However what really gets me is that the car drives totally fine, and still goes fast as ****. I guess I'm going to run TXMC then take the head off and have a look. If the valves are burnt we're switching to Inco exhaust valves with Berrylium seats. This is weird. Just to be sure I was at TDC I rotated the engine from -5* to +5* to make sure the exhaust valves were closed and never saw a real change in the leak gauge. I'm guessing it's not the tester hose since I always heard air through the exhaust.
#18
Are you doing the test correctly on a fully charged battery? Five to six cranks wot on each cylinder should do it.
With the leakdown, make sure all valves are closed and only run like 30-40 psi at first.
With those numbers, the engine would barely stay running, you should be up in the 180's at least.
With the leakdown, make sure all valves are closed and only run like 30-40 psi at first.
With those numbers, the engine would barely stay running, you should be up in the 180's at least.
#19
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Are you doing the test correctly on a fully charged battery? Five to six cranks wot on each cylinder should do it.
With the leakdown, make sure all valves are closed and only run like 30-40 psi at first.
With those numbers, the engine would barely stay running, you should be up in the 180's at least.
With the leakdown, make sure all valves are closed and only run like 30-40 psi at first.
With those numbers, the engine would barely stay running, you should be up in the 180's at least.
Savington to reminded me of valve lash. I had to adjust it a few years ago, maybe I went a tick too far.