Compression results / need advise

[rn240sx]

As i posted a while back my compression results came back as 210 on all 4 cyinders. Possible due to the carbon build up cause when i pulled the tester out of the spark plug hole, i had black smudge or "carbon buildup" all over the threading, not much but enough to notice...

What causes this carbon buildup...???

Is it safe to push 15 psi thru this motor being it has this build up and due to the high compression results..??

[Structure240sx]

i beleive its just from years of use and dirt, oil grime building up? you could probably get rid of a lot of it using seafoam.

slos13 was boosting 15-16psi on his 200k mi motor with compression readings of 195 across or 210. it depends on your tune more than anything.

maxima guys have 10:1+ compression ratio and boost 13+psi on stock ecu's. there timing stock is in the lower 20 degrees. people make 350+fwhp all day with those

[rn240sx]

i beleive its just from years of use and dirt, oil grime building up? you could probably get rid of a lot of it using seafoam.

slos13 was boosting 15-16psi on his 200k mi motor with compression readings of 195 across or 210. it depends on your tune more than anything.

maxima guys have 10:1+ compression ratio and boost 13+psi on stock ecu's. there timing stock is in the lower 20 degrees. people make 350+fwhp all day with those

What is this Seafoam stuff and how does work..?? IS this something that a machine shop uses or something that i just drop down the spark plug hole and let it eat away on that buildup crap... Or does the motor have to be opened up to use this seafoam..??

[PapaSmurf2k3]

do a thread search for seafoam.

You can buy it at NAPA. pour it through the brake booster hose, and it will clean the crap out of everything... and make a really huge smoke cloud in the process. You dont have to take anything apart on the motor, except disconnect the brake booster hose. It is reccomended you replace the spark plugs and O2 sensor after you do it though.

[rn240sx]

Yeah I found it.. Well i guess i have to remove the wideband and place the stock one back in and buy new plugs afterwards..Then this should bring my compression back down to 180... HOPEFULLY

[rn240sx]

do a thread search for seafoam.

You can buy it at NAPA. pour it through the brake booster hose, and it will clean the crap out of everything... and make a really huge smoke cloud in the process. You dont have to take anything apart on the motor, except disconnect the brake booster hose. It is reccomended you replace the spark plugs and O2 sensor after you do it though.

Ok, i did the seafoam stuff and i got a pretty descent size of white smoke for about 2 minutes worth...

I dont have the oem O2 sensor, i have my wideband sensor in its place and the bottle said that the stuff is o2 sensor safe... If it went bad then ill just buy a replacement one (no big deal) I have a new set of lugs anyway to replace if these went bad...

I was just curious to know how long b4 i can do another compression test on this motor... Its been about a good 30 minutes since i shut the motor off after dropping in the seafoam stuff...

[rn240sx]

Ok, i just got back from doing the compression test after using that seafoam and i go the SAME identical results...

210-210-210-210

But this time, there was NO carbon build up on the tip of the fitting like there was last time..