Compression Test results im confused
01-28-08, 06:04 PM
#26
ok so what I am reading into after looking at all of this.
If the motor is brand new or freshly rebuilt it will result in 100psi on all rotors....
Now with that being said, and engine that is 16 years old and does score a compression test of 80psi all round is technically "good". THis is obviously do to obsolence wear and tear. So technically the this is a pretty darn good score for a car that still has all stock motor in it.
Now, The way i see it, unless you have a fresh motor your going to be in the range of 80-90 if the car has over 50k mils on it.
My car is not used for racing or crazy erratic driving.
I have had it for 4 years and its rarely seen over 6k rpms.
And the owner before me was an older gentlemen who traded it in for a Porche, and he also just drove it for pleasure sunday drives.
Now with that being said, I beleive my asking price of $22k is a fair starting point a I am not looking to just accept the first low ball offer i see.
THis car is really well taken care of, yes the car is 16 years old, and does show a small bit of obsolence on the exterior and engine, but it runs fine for someone who is looking for a nice partially stock rx7.
If the motor is brand new or freshly rebuilt it will result in 100psi on all rotors....
Now with that being said, and engine that is 16 years old and does score a compression test of 80psi all round is technically "good". THis is obviously do to obsolence wear and tear. So technically the this is a pretty darn good score for a car that still has all stock motor in it.
Now, The way i see it, unless you have a fresh motor your going to be in the range of 80-90 if the car has over 50k mils on it.
My car is not used for racing or crazy erratic driving.
I have had it for 4 years and its rarely seen over 6k rpms.
And the owner before me was an older gentlemen who traded it in for a Porche, and he also just drove it for pleasure sunday drives.
Now with that being said, I beleive my asking price of $22k is a fair starting point a I am not looking to just accept the first low ball offer i see.
THis car is really well taken care of, yes the car is 16 years old, and does show a small bit of obsolence on the exterior and engine, but it runs fine for someone who is looking for a nice partially stock rx7.
Tim
01-29-08, 10:17 AM
#28
ok so what I am reading into after looking at all of this.
If the motor is brand new or freshly rebuilt it will result in 100psi on all rotors....
Now with that being said, and engine that is 16 years old and does score a compression test of 80psi all round is technically "good". THis is obviously do to obsolence wear and tear. So technically the this is a pretty darn good score for a car that still has all stock motor in it.
Now, The way i see it, unless you have a fresh motor your going to be in the range of 80-90 if the car has over 50k mils on it.
If the motor is brand new or freshly rebuilt it will result in 100psi on all rotors....
Now with that being said, and engine that is 16 years old and does score a compression test of 80psi all round is technically "good". THis is obviously do to obsolence wear and tear. So technically the this is a pretty darn good score for a car that still has all stock motor in it.
Now, The way i see it, unless you have a fresh motor your going to be in the range of 80-90 if the car has over 50k mils on it.
My FC has 25k on the motor and still reads 120+ psi. all around.
Unless the gauge or information is wrong, 80 psi isn't a good score. Period.
FYI, when I obtained my FD it read 80 psi. I didn't even try to run it. I immediately started tearing it down for a rebuild.
As far as holding the throttle open, in my experience it makes a difference. ~10 psi or more on my gauge
01-29-08, 01:32 PM
#29
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Not at all. Ideally, a fresh motor will make 132.3 psi. This is based on atmospheric pressure and the 9.0:1 compression ratio of the 13B-REW rotor.
My FC has 25k on the motor and still reads 120+ psi. all around.
Unless the gauge or information is wrong, 80 psi isn't a good score. Period.
FYI, when I obtained my FD it read 80 psi. I didn't even try to run it. I immediately started tearing it down for a rebuild.
As far as holding the throttle open, in my experience it makes a difference. ~10 psi or more on my gauge
My FC has 25k on the motor and still reads 120+ psi. all around.
Unless the gauge or information is wrong, 80 psi isn't a good score. Period.
FYI, when I obtained my FD it read 80 psi. I didn't even try to run it. I immediately started tearing it down for a rebuild.
As far as holding the throttle open, in my experience it makes a difference. ~10 psi or more on my gauge
01-29-08, 06:46 PM
#30
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I'm surprised this thread is still going. Even if you had good compression today, apex seals may break for a few reasons including age factors. do you have no miles on the car?
Are our cars that much now?
Are our cars that much now?
01-29-08, 08:32 PM
#31
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The car has 77k miles on it,.
01-29-08, 08:33 PM
#32
Of course this is all theoretical. No ones surfaces are that perfect and most gauges are probably off a few psi.
When you leave the throttle closed the reading will be lower because the rotor will be compressing air that is at less than atmospheric pressure.
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