i checked the compression on my motor at about 140k and they were all between 125 and 135, most over 130. The car has now 145,000 on it. I was just curious how long do you guys think it will be before i start losing serious amounts of horsepower, and how fast does the compression decrease.

 

anyone have an idea?

 

Well mine checked in at 110 with 192,000 on the clock, and I can definatly tell the difference. Keep in mind tho, I have 100 less horse and torque to start with than yours. I would say that you might be ok up to 165k then a rebuild is a must.

 

it's a matter of how hard you abuse it,and how well you take care of it.
i have seen motors getting rebuilt with less than 10k,and some still screaming with over 200,000.
your compression is fine by ford standards...actually better..

 

I checked mine at 165k and there around that 130-150. The lowest reading cylinder must be within 15 psi of highest reading cylinder (100 psi minimum).