i think its actully 8.2:1
but in all reallity how much iam i going to notice the differance 3% ? with a weber instead of stock and a header?

umm ok ive seen two diffenrnt numbes posted the 8.2 and the 8.7 oh well numbers.
so iam getting the gasket kit, oil pump. lifters and the rod and crank bearing for 170.

From the 89fsm - 8.7:1
from the 87fsm - 7.0:1 (it's wrong)
from the 84fsm - 8.2:1

I never knew it changed - probably in 87, and the genius fsm writer left off the "8.", or they just used the starquest number...

i know the older 2.6 had differnt rings
first two are 1.5mm the third being 4mm
and the older were 2mm and 4mm
i migt have got that backwards

KevinC is the old 2.6 guru - been hot rodding the motor for years - bet he will chime in.

The later rings were thinner to reduce friction. The power difference from the CR change will be about 5% since your dropping the compression from 8.7 to 7 or about 5 to 7 HP.

Many re-builder pistons are decked and drop the CR by another 1/2 point. The idea is to account for milled cylinder heads. Just a warning that you may end up with a real CR of 6.5 to 1.

If the rods were overloaded, the upper bearings should be worse. If the damage is the same, it might be from air in the oil or cavitation.

That would explain why the crank was still OK.

One note on oil pumps.

Starion pump is superior. However, the pickup sits higher because the starion pan is shallower than the monty pan. I welded in a section of the truck pickup tube in the drop section of the starion pickup to space it down a hair under an inch. May have been overkilll, as it only matters if the oil level is low, but wheeling angles worried me. Would not have done it in a street car, probably...

oil pump thought. i havent pull it apart if it come aparts.
but i do have two or three oil pumps. two from starquest that looks new one older looking from truck. do they come apart and what is the change of being ablea to but the back on the starion pump so it can pick up through block passage. and just plug the other?

ok got word back from machine shop crank spec looked good and polished it. the head a brought to him check not crack is getting ready to resurface can pick up later to day not bad drop it off to him last night right as he was going home. $ 105 for shop. $150 for motors. $300 for buying back raider. $10 junkyard parts. oh and will need a new starter

alright been a little busy but i got my parts and have got to work. let me tell you an engine stand would be quite nice. oh well adapte and over come. got crank and plastigauged main and rods look good well in spec. put rings on pistion and inserted with a nice fresh hone job. picked the better looking of the three cams and put some fresh lash adjusters i did prime them. primed oil pump and put on threw some new guide rails and put timeing chain and gear along with oil pump and crank gear has b/s kit installed.. getting ready to put timing cover oil pan and head on.