PISTONS Remove sharp edges from head surface of piston For installation of rods using pressed in wrist pins it is necessary to heat the rod small end and install the pins qui in a fixture Most 5 automotive machine shops are equipped Sy this assembly It is necessary to have at least O0l or erably 00l2 press fit between wrist pins and rods to ins that pins will not loosen and move during running Pistons with floating n use Spirolox or Truarc pin retainers The squared off edge tainer sho qv face away from the end of the pin towards t Q ig der sh ad e will tend to bite into the pist hh w D E Em 5 3 FD pulled out Make sure there is a ii pla retainers ins d Do not reuse wrist pin r ainer n as en n e 1970 Spirolox Retainer wa t c wu A 1 5 Q O72 This retainer if carefully regrcvved to restore L e r shi l or i increased durability V 1 va Qs yr V Run the production Moly groov ype is or bes ow by control and minimum friction 1 For Heavy Duty operation it is good practice to allow more than the minimum piston to valve clearances to allow for occasional valve float A 100 clearance is generally acceptable minimum Q 396 427 454 CID 427 CID 3 3959105 PISTON Std floating pin use w 3946072 head 8 3909857 PISTON Std floating pin use w 39 9838 head B 3909858 PISTON 001 O S floating pin use w 3919838 head 8 3959106 PISTON 001 0 5 floating pin use w 3946072 head 8 3981891 PISTON 005 0 S floating pin use w 3946072 head 8 A 3909859 PISTON 030 0 5 floating pin use w 3919838 head 8 j 3959107 PISTON 030 0 5 floating pin use w 3946072 head 8 i 3909860 PISTON 060 0 S floating pin use w 3919838 head 8 I 3964238 RETAINER Piston Pin floating pin ick AR 1 454 cm I I 3976014 PISTON Std forged use w 3946072 ead S 3976018 PISTON 00l 0 S forged use w 394 072 head I 8 4 3976022 PISTON 020 0 5 forged use w 394 072 head 8 3976026 PISTON 030 0 S forged use w 394 8 u 3981075 pxsmom 060 0 s forged use w 29 a 3964238 RETAINER Piston Pin floating pin hick AR nz UV NO l E Also use with Crankshaft 3963524 Bala r 3530 I and Flywheel 3963537 21 ll 16 70 r 1r 1 1 1rl 1