#11




I basically use the information here to determine what the specification (from sea level) becomes at a given altitude. At 5,000 feet (Longmont) the specification range in the F engine FSM (128 to 150) becomes 110 to 129. At 7,000' the range becomes 122 to 104.
Use the chart in that link to figure out what the range becomes at the altitude you did the compression test at, then see how your numbers compare. Last edited by RicardoJM; 12172010 at 10:24 AM. 
#12




So I did the test at my parents house which is at 7000 ft or so. According to that chart the multiplication factor is about .813 (linear between 6500 ft and 7500 ft).
So my numbers, adjusted for altitude, are: #1  141 #2  141 #3  135 #4  125 #5  135 #6  138 Okay, so that's not too bad. Even if it's closer to 6500 ft, they are: #1  139 #2  139 #3  133 #4  123 #5  133 #6  136 I feel much better now.
__________________
Matt Miller TLCA# 13684 Rising Sun Bio 1977 FJ40 2F "Brahma" + Lockright, tach, Warn 8274, FJ60 Power Steering, no more Sanden OBA (factory emissions) 1996 FZJ80 1FZFE factory lockers + Safari Turbo , CDL switch, cup holder, Metric TLC leather, heated seats and JDM switches 2000 Tundra Limited TRD 2UZFE SOLD 
#13




So what were your readings directly from the gauge? At 7,000 feet the adjusted range is 122 to 104.
Whether you adjust your readings or adjust the range and compare you actuals shouldn't matter, but I'm used to adjusting the range. It is easier for me to not have to do the math on each reading. 
#14




First post; 102115 wet test.
__________________
Matt Miller TLCA# 13684 Rising Sun Bio 1977 FJ40 2F "Brahma" + Lockright, tach, Warn 8274, FJ60 Power Steering, no more Sanden OBA (factory emissions) 1996 FZJ80 1FZFE factory lockers + Safari Turbo , CDL switch, cup holder, Metric TLC leather, heated seats and JDM switches 2000 Tundra Limited TRD 2UZFE SOLD 
#15




Quote:
Take the gauge reading of 113 and divide it by .79 which equals 143. Thats close to being within 10% of spec which is 150 psi at sea level. If all of the cylinders are roughly within 10% of each other, then your motor is in pretty excellent condition.
__________________
Randy Rosetta KDØKWX TLCA #19351 NOW 2015 Rubicon Hard Rock & (2) 1970 Boss 302 Mustang's THEN 69 FJ40 Buggy "Meanie", Minitruck "Gecko" & 74 FJ40 "Blue Mule" 
Thread Tools  

