it is recommended that the FC connecting rod rule be updated to the form used for Kents. the update would be administratively sound and provide competitors a compliant means to improve bottom end service interval.
for reference the FFord rule is included below:
12. Kent Engine
j. Connecting Rods
Any ferrous connecting rod may be used provided it meets a minimum weight of 630 grams and has a center to center length of 4.925 +/- 0.020 inches. (Note: Weights include cap, bolts, and small end bush, but not big end bearing shells).
the current FC rule reads:
15. Ford NE series and Pinto Engines
h. Full connecting rods may be standard Ford, Cosworth, Oliver, or Crower. The approved Crower part numbers are SP93230B-4 or SP93230PF-4. Any rod bolts may be used. Floating piston pins may be used. Standard rod length must be 5.00 inches (+.005” -.010”). Machining is permitted to remove metal from the balancing bosses to achieve balance only. Tuftriding, Parkerizing, shot peening, shot blasting, polishing, etc., are permitted
the recommended update would read:
h. any ferrous connecting rod may be used provided its length between the small end and large end is 5.00 inches (+0.005" -0.010") and when installed is compliant with 15. f. wrist pins are unrestricted provided no modification is made to the piston for installation and when installed is compliant with 15. f.
as an aside, floating pins are already unrestricted. the recommended update would extend "unrestricted" to pressed pins and explicitly exclude modification to the piston for installation.
for reference:
15. Ford NE series and Pinto Engines
f. Pistons shall be standard Ford Mahle, AE Hepolite, CP, or J&E. Pistons must be unmodified in any way except for balancing and as detailed herein.
The following combinations are permitted:
1. Mahle piston P/N 80HM6102LA with rings, pin, connecting rod
(with bolts), but without bearings:Minimum permitted weight = 1332.5 grams.
2. Mahle piston P/N 85HM6102DA with rings, pin, connecting rod (with bolts), but without bearings: Minimum permitted weight = 1240 grams.
NOTE: This piston may have either casting #90V108 or #90V118.
3. AE Hepolite piston P/N 21426, casting P/N 21426 (AE Hepolite) with rings, pin, connecting rod (with bolts), but without bearings: Minimum permitted weight = 1240 grams.
4. CP piston P/N IV 2.0 LTR with rings, pin, connecting rod (with bolts), but without bearings: Minimum permitted weight = 1240 grams. Part number and Ivey logo stamped on wrist pin bosses.
5. JE piston P/N M-6102-B200 with rings, pin, connecting rod (with bolts), but without bearings: Minimum permitted weight = 1240 grams.
NOTE: M-6102-B200 piston assembly is now made by JE and is visually different. I.D. Marks: M-6102-B200, Ford racing logo. All marks pin stamped on wrist pin bosses.
Rings are unrestricted provided that:
A. One oil control and two compression rings are used.
B. No modification is made to the piston for the installation of the rings.
Localized machining of the gudgeon pin bosses to achieve balance and weight by simple machining; all external surfaces, dimensions, and profiles shall remain standard with the exception of the top surface of the piston crown which may have simple machining to achieve balance, and as required in Section 9.1.1.B.3.d.
Art
artesmith@earthlink.net