desired compression psi

McGillicuddy · #1 10-16-2009, 10:17 PM

Just wondering how to determine desired compression for 83 Merc 115 i-6? Can't find it in my Mercury service manual... Thanks.

Also going to look at 2.0 150 hp XR2 tomorrow. Any opinions as compared to a 2.4L? performance, economy etc...?

stumpie2 · #2 10-17-2009, 10:20 AM

usually a manual wont give you a set number but you should be in the neighborhood of 120-140 the main factor is that there is no more than 10 lbs or 10% difference in all of the cylinders.

Fr. Frank · #3 10-17-2009, 03:12 PM

Quote:

...in the neighborhood of 120-140 the main factor is that there is no more than 10 lbs or 10% difference in all of the cylinders.

That's right on. Spec is 125 lbs for a '77 115, I don't have any other to hand.

Tim (BigShrimpin) is the guy to ask about the 2.0 vs 2.4 Mercs. I think they are both great motors. I know the 2.0L was made in 135, 150, 175, and 200 hp models, and the 2.4L was made out to 225hp.

McGillicuddy · #4 10-17-2009, 11:14 PM

Thanks guys.