ka24de compression results- kinda odd.

[gotta240]

I NEVER EVER believe what people tell me when i buy a car. I try to let the car speak for itself to solve the "puzzle" of its own history. Help me solve my newest puzzle.

Stock LOOKING ka24de in 96 240sx. Chassis has 200k miles on it. Previous owner SAID the motor was replaced sometime, and the head was ported/polished. When i changed the oil it was SUPER dirty, but no metal signs. Plugs were super old.. Basically not typical of someone who would pay for a port polish(although it doesnt do much good on a ka head anyways)

NOW... The compression results were

170 180 190 180

Although i'm not thrilled with the 170, its not terrible. The thing that trips me out is the 180 and 190's. Those numbers are higher than any ka i've had before. I've had very well running ka's give me 160 and 170 across.

SO, with those numbers would you say

1. the head has been shaved?
2. Its just a good motor and those comp. results are normal?
3. the engine is a piece of shit with tons of carbon?
4. fill in the blank.

whatcha think?

[redpotatoes]

Mine has 180 across the 4 cylinders and it's running in perfect condition. I thought factory compression was 179 or something like that.

Compression Pressure kPa (kg/cm2, psi) / RPM
Standard = 1,236 (12.6, 179) / 300
Minimum = 1,040 (10.6, 151) / 300
Difference limit between cylinders = 98 (1.0, 14) / 300

[hstylez]

SO, with those numbers would you say

1. the head has been shaved?
2. Its just a good motor and those comp. results are normal?
3. the engine is a piece of shit with tons of carbon?
4. fill in the blank.



Either of the above that you said could be true. At any rate, those numbers arn't bad at all really. If i had to guess, when the P&P was done the desk could have been resurphased and it could be slightly smaller than stock, giving you a slightly higher compression. Who knows though... How does it drive?

[98s14inaz]

Either of the above that you said could be true. At any rate, those numbers arn't bad at all really. If i had to guess, when the P&P was done the desk could have been resurphased and it could be slightly smaller than stock, giving you a slightly higher compression. Who knows though... How does it drive?

I concur. It's a ka. If it runs fine and no other issues don't worry about it.