ls2 402 compression test ?????
#1
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ls2 402 compression test ?????
hi
i justed finished closing my motor after few changes made....
i´m running
TSP ls2 402
Wiesco -8cc dish
Tx giant cam 248-254, 615.622 114
GM 6.0/6.2 head gasket 4layers .06"
TFS 215cc was milling them from 65cc down to 57.5cc and opened up the chambers for 4" and ended up whith 59cc
was given up that it should bump my compression from 10.95:1 to 11.6:1
and did a compression test after starting the motor up for 2 minutes.
i only tooke 2 spark plugs out each side of the block.
and got only 182ish and 185ish out of the test.
was hoping to see above 200ish, because i did a test on the car last summer and it shoved then from 180-195, but then the motor was hotter and all of the spark plugs where out at the time i did it, and the year before i did a test on my 346 that was around 10.9-11 CP and it shoved 185-200ish then all spark plugs out.
all done whith the same tester.....
can this be normal....?, should i not see increase on the testing...
should it change anything to take all the s.plugs out and have the motor/oil hot before i do the test....
if my motor is 11.6:1 what should i be seeing on the tester.
But the car pulls now like a i can feel the diffrence but i made also few other changes that can be bluffing..... fast/TB and bigger headers
thanks Baezi
i justed finished closing my motor after few changes made....
i´m running
TSP ls2 402
Wiesco -8cc dish
Tx giant cam 248-254, 615.622 114
GM 6.0/6.2 head gasket 4layers .06"
TFS 215cc was milling them from 65cc down to 57.5cc and opened up the chambers for 4" and ended up whith 59cc
was given up that it should bump my compression from 10.95:1 to 11.6:1
and did a compression test after starting the motor up for 2 minutes.
i only tooke 2 spark plugs out each side of the block.
and got only 182ish and 185ish out of the test.
was hoping to see above 200ish, because i did a test on the car last summer and it shoved then from 180-195, but then the motor was hotter and all of the spark plugs where out at the time i did it, and the year before i did a test on my 346 that was around 10.9-11 CP and it shoved 185-200ish then all spark plugs out.
all done whith the same tester.....
can this be normal....?, should i not see increase on the testing...
should it change anything to take all the s.plugs out and have the motor/oil hot before i do the test....
if my motor is 11.6:1 what should i be seeing on the tester.
But the car pulls now like a i can feel the diffrence but i made also few other changes that can be bluffing..... fast/TB and bigger headers
thanks Baezi
#2
Did you change the cam? More duration? That has an effect on cold cranking compression more duration will lessen the cold cranking compression but changes as the motor is started and running. static compression.
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the cam is the same as i have had all the time on the 402ci, but on the old setup stock bottom ls6 346 i was running 232 234.595 598 112 cam
now ls7 lifters and am still using te same pushrods 7.700"
should i see some others numbers if i let the engine be hot and CP test then? you think?
thanks
Baezi
#4
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A wram test with all the plugs out will give very different results. Compression tests are for balance checking between cylinders and to get a general idea of the condition, they are not a measurement of compression ratio. If it runs great and pulls like you say - enjoy it - don't keep trying to measure it. There's a compression calculator on here if you want to try to do the math.
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i ran the car until it was hot
went into te garage and tooke all spark plugs out and fuel fuses out to.
The test was 4-5 crank rings at WOT.
results 190-190-205-190-195-205-185
it´s better.... i think.
baezi
went into te garage and tooke all spark plugs out and fuel fuses out to.
The test was 4-5 crank rings at WOT.
results 190-190-205-190-195-205-185
it´s better.... i think.
baezi