Moly Ring Sets
Part No. BORE Ring Widths
SPE251K STD** 4.00” (5/64 X 5/64 X 3/16)
SPE251K 020** 4.00” (5/64 X 5/64 X 3/16)
SPE251K 030** 4.00” (5/64 X 5/64 X 3/16)
SPE251K 040** 4.00” (5/64 X 5/64 X 3/16)
SPE251K 060** 4.00” (5/64 X 5/64 X 3/16) NOTE:** 4.00” Bore: fits Ford 289, 302, 351, 400 ci, Chev 327, 350, Holden 304, 308 and Chrysler 360
SPE245K STD CHEV 283-307 3.875”
SPE245K 020 CHEV 283-307 3.875”
SPE245K 030 CHEV 283-307 3.875”
SPE245K 040 CHEV 283-307 3.875”
SPE245K 060 CHEV 283-307 3.875”
SPE356K STD CHEV 305 3.736”
SPE356K 020 CHEV 305 3.736”
SPE356K 030 CHEV 305 3.736”
SPE356K 040 CHEV 305 3.736”
SPE356K 060 CHEV 305 3.736”
SPE938K 25MM CHEV 346 LS1 3.900
SPE938K STD CHEV 346 LS1 3.900
SPE243K STD CHEV 400 4.125”
SPE243K 020 CHEV 400 4.125”
SPE243K 030 CHEV 400 4.125”
SPE243K 040 CHEV 400 4.125”
SPE243K 060 CHEV 400 4.125”
SPE233K STD CHEV 427-454 4.250”
SPE233K 020 CHEV 427-454 4.250”
SPE233K 030 CHEV 427-454 4.250”
SPE233K 040 CHEV 427-454 4.250”
SPE233K 060 CHEV 427-454 4.250”
SPE233K 100 CHEV 427-454 4.250”
SPE239K STD CHRYS 273 3.625”
SPE239K 030 CHRYS 273 3.625”
SPE239K 040 CHRYS 273 3.625”
SPE239K 060 CHRYS 273 3.625”
SPE178K STD CHRYS 318 3.910”
SPE178K 020 CHRYS 318 3.910”
SPE178K 030 CHRYS 318 3.910”
SPE178K 040 CHRYS 318 3.910”
SPE178K 060 CHRYS 318 3.910”
SPE286K STD CHRYS 340 4.040”
SPE286K 020 CHRYS 340 4.040”
SPE286K 030 CHRYS 340 4.040”
SPE286K 040 CHRYS 340 4.040”
SPE286K 060 CHRYS 340 4.040”
SPE424K STD CHRYS 440 4.320”
SPE424K 020 CHRYS 440 4.320”
SPE424K 030 CHRYS 440 4.320”
SPE424K 040 CHRYS 440 4.320”
SPE424K 060 CHRYS 440 4.320”
SPE296K STD FORD 429-460 4.360”
SPE296K 020 FORD 429-460 4.360”
SPE296K 030 FORD 429-460 4.360”
SPE296K 040 FORD 429-460 4.360”
SPE296K 060 FORD 429-460 4.360”
SPE239K STD HOLDEN 253 3.625”
SPE239K 030 HOLDEN 253 3.625”
SPE239K 040 HOLDEN 253 3.625”
SPE239K 060 HOLDEN 253
 3.625”
Cast Ring Sets
Part No. BORE Ring Widths
SPE251X STD** 4.00” (5/64 X 5/64 X 3/16)
SPE251X 020** 4.00” (5/64 X 5/64 X 3/16)
SPE251X 030** 4.00” (5/64 X 5/64 X 3/16)
SPE251X 040** 4.00” (5/64 X 5/64 X 3/16)
SPE251X 060** 4.00” (5/64 X 5/64 X 3/16)
NOTE:** 4.00” Bore: fits Ford 289, 302, 351, 400 ci, Chev 327, 350, Holden 304, 308 and Chrysler 360
SPE245X STD CHEV 283-307 3.875”
SPE245X 020 CHEV 283-307 3.875”
SPE245X 030 CHEV 283-307 3.875”
SPE245X 040 CHEV 283-307 3.875”
SPE245X 060 CHEV 283-307 3.875”
SPE356X STD CHEV 305 3.736”
SPE356X 020 CHEV 305 3.736”
SPE356X 030 CHEV 305 3.736”
SPE356X 040 CHEV 305 3.736”
SPE356X 060 CHEV 305 3.736”
SPE243X STD CHEV 400 4.125”
SPE243X 020 CHEV 400 4.125”
SPE243X 030 CHEV 400 4.125”
SPE243X 040 CHEV 400 4.125”
SPE243X 060 CHEV 400 4.125”
SPE233X STD CHEV 427-454 4.250”
SPE233X 020 CHEV 427-454 4.250”
SPE233X 030 CHEV 427-454 4.250”
SPE233X 040 CHEV 427-454 4.250”
SPE233X 060 CHEV 427-454 4.250”
SPE239X STD CHRYS.273 3.625”
SPE239X 020 CHRYS.273 3.625”
SPE239X 030 CHRYS.273 3.625”
SPE239X 040 CHRYS.273 3.625”
SPE239X 060 CHRYS.273 3.625”
SPE178X STD CHRYS.318 3.910”
SPE178X 020 CHRYS.318 3.910”
SPE178X 030 CHRYS.318 3.910”
SPE178X 040 CHRYS.318 3.910”
SPE178X 060 CHRYS.318 3.910”
SPE286X STD CHRYS.340 4.040”
SPE286X 020 CHRYS.340 4.040”
SPE286X 030 CHRYS.340 4.040”
SPE286X 040 CHRYS.340 4.040”
SPE286X 060 CHRYS.340 4.040”
SPE424X STD CHRYS.440 4.320”
SPE424X 020 CHRYS.440 4.320”
SPE424X 030 CHRYS.440 4.320”
SPE424X 040 CHRYS.440 4.320”
SPE424X 060 CHRYS.440” 4.320
SPE296X STD FORD 429-460 4.360”
SPE296X 020 FORD 429-460 4.360”
SPE296X 030 FORD 429-460 4.360”
SPE296X 040 FORD 429-460 4.360”
SPE296X 060 FORD 429-460 4.360”
SPE239X STD HOLDEN 253 3.625”
SPE239X 020 HOLDEN 253 3.625”
SPE239X 030 HOLDEN 253 3.625”
SPE239X 040 HOLDEN 253 3.625”
SPE239X 060 HOLDEN 253 3.625”
Speed-Pro High Performance Piston Ring Sets

Piston rings don’t make horsepower - they prevent it’s loss. They do this by controlling and minimizing cylinder leakage under true operating conditions, and by keeping oil, which can cause detonation, out of the combustion chamber. Speed-Pro ring sets feature plasma-moly faced ductile iron top rings for nearly instant ring seating, superior cylinder sealing and optimum durability under the most grueling conditions.
Top and second rings are available in “File-Fit” versions, which allow the engine builder to tailor critical end gaps to the specific needs of their application.
SPEED-PRO HAS WON MORE RACES THAN ALL THE OTHER PISTON RING BRANDS COMBINED!
Plasma Moly File Fit Ring Sets
Part No. BORE Ring Widths
SPR9342 005 4.000” (1/16 X 1/16 X 1/8)
SPR9342 025 4.000” (1/16 X 1/16 X 1/8)
SPR9342 035 4.000” (1/16 X 1/16 X 1/8)
SPR9342 045 4.000” (1/16 X 1/16 X 1/8)
SPR9342 065 4.000” (1/16 X 1/16 X 1/8)
SPR9343 005 4.000” (5/64 X 5/64 X 3/16)
SPR9343 025 4.000” (5/64 X 5/64 X 3/16)
SPR9343 035 4.000” (5/64 X 5/64 X 3/16)
SPR9343 045 4.000” (5/64 X 5/64 X 3/16)
SPR9343 065 4.000” (5/64 X 5/64 X 3/16)
SPR9771 005 4.000” (1/16 X 1/16 X 3/16)
SPR9771 025 4.000” (1/16 X 1/16 X 3/16)
SPR9771 035 4.000” (1/16 X 1/16 X 3/16)
SPR9771 045 4.000” (1/16 X 1/16 X 3/16)
SPR9771 065 4.000” (1/16 X 1/16 X 3/16)
SPR9786 005 4.000” (.043 X 1/16 X 3/16)
SPR9786 035 4.000” (.043 X 1/16 X 3/16)
SPR9786 065 4.000” (.043 X 1/16 X 3/16)
SPR9401 005 4.000” (1/16 X 1/16 X 3/16) Low Tension.
SPR9401 035 4.000” (1/16 X 1/16 X 3/16) Low Tension.
SPR10248 005 4.125” (1/16 X 1/16 X 3/16)
SPR10248 035 4.125” (1/16 X 1/16 X 3/16)
SPR5879 005 4.125” (5/64 X 5/64 X 3/16)
SPR5879 035 4.125” (5/64 X 5/64 X 3/16)
SPR5879 065 4.125” (5/64 X 5/64 X 3/16)
SPR9344 035 4.250” (1/16 X 1/16 X 3/16)
SPR9344 065 4.250” (1/16 X 1/16 X 3/16)
SPR9344 005 4.250” (1/16 X 1/16 X 3/16)
SPR9590 005 4.250” (5/64 X 5/64 X 3/16)
SPR9590 035 4.250” (5/64 X 5/64 X 3/16)
SPR9590 065 4.250” (5/64 X 5/64 X 3/16)
SPR9745 005 4.250” (1/16 X 1/16 X 3/16)
SPR9788 005 4.250” (.043 X 1/16 X 3/16)
SPR9788 035 4.250” (.043 X 1/16 X 3/16)
SPR9788 065 4.250” (.043 X 1/16 X 3/16)
SPR9799 005 4.375” (1/16 X 1/16 X 3/16)
SPR10133.005 4.440” (1/16 X 1/16 X 3/16)
SPR10133.035 4.440” (1/16 X 1/16 X 3/16)
SPR10598 13 3.900 (1.5 X 1.5 X 3mm)
SPR10598 38 3.900 (1.5 X 1.5 X 3mm)
SPR9902 030 4.000” (1/16 X 1/16 X 3/16)
SPR9902 060 4.000” (1/16 X 1/16 X 3/16)
SPR9902 STD 4.000” (1/16 X 1/16 X 3/16)
SPR9903 030 4.000” (5/64 X 5/64 X 3/16)
SPR9904 030 4.250” (1/16 X 1/16 X 3/16)
SPR9904 060 4.250” (1/16 X 1/16 X 3/16)
SPR9904 STD 4.250” (1/16 X 1/16 X 3/16)
SPR9968 030 4.000” (1/16 X 1/16 X 1/8)
SPR9968 060 4.000” (1/16 X 1/16 X 1/8)
SPR9968 STD 4.000” (1/16 X 1/16 X 1/8)
SPR10375 030 4.125” (1/16 X 1/16 X 3/16)
SPR10375 STD 4.125” (1/16 X 1/16 X 3/16)