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I finally got my block, rods, and crank back from the machinist. I just realized that I don't know the correct torque specs for the bottom end. I need the main cap, and rod bolt specs. Also, what is the gap of the rings supposed to be? Can anyone help me out? I would like to start putting it together this weekend, but I don't have all my parts yet. (still waiting) Thanks in advance for any info.. P.s. These are not aftermarket bolts, or pistons.
Rod Bolts torque is (the nut) is 45 ft lbs, Main caps is "inboard " bolts on four bolt main is 78 ft lbs, and outer bolts are 68 ft lbs. Service manual for 93 LT-1 Corvette page 6A1A-31.
Piston ring gap: Upper-.010"-020", lower ring .018"-.026" MAX, service limit .035". Oil ring is .010-.030"" service limit .065" MAX.
This is right out of the service manual. Hope this helps Steve
Thank you, I will go with those specs. By the way, that picture of your car is pretty cool. I live in Washington State and haven't seen a clean vette in awhile. I haven't driven one in awhile either!!! Have a good weekend..
I also forgot to get the bearing clearances for the mains and the rods. They measure about 3.5-4 thousanths on the mains and .002 on the rods. That sounds about right to me. What does the book say?
Rod bearing clearances: .013-.035" max Rod Side clarance: .006-.014" max
Main bearings: #1 main- .0008-.0002", #2,3,4 main-.0011-.0020"max, #5 main .0017-.0032" max.
Ok, I assume that you mean .0008-.002 on #1? My next question is, holly crap are the mains really supposed to be that tight? Mine are twice that. I could almost live with the #5 specs, but I must have problems.
Steve, thanks for the info. My chiltons and haynes say pretty much the same thing. I don't usually put much faith in those books. Ok, now that I know that my clearances are double what they should be, what do i do. I have built several engines, but they have always been "in spec". I had the main line bored, and the crank turned. I couldn't tell wich one is screwed because I used plasi-gauge to check clearances. This pisses me off big time. Machining isn't cheap and for the money a guy forks out you expect quality. This is what these guys do for a living. Maybe I am jumping to conclusions, I will borrow or buy some micrometers tomorrow and get to the bottom of this.
If you have 0.0035-0.004 you are good, when they line hone the block they check the crank and hone the mains until they have the right clearance for that crank even if it is turned 0.010.
The rods are a little tight but I would not vorry about it.