[DeTomaso] A3 data & Rods

[JDeRyke at aol.com]

In a message dated 9/29/06 5:45:00 AM, charlesbuthala at yahoo.com writes:

<< Con Rods PN D0AE-A  (Stock?)
  Two Con Rods were measured vie CMM
  Cyl # 8 148.471 mm (5.845315")
  Cyl # 6 148.429 mm (5.843661")
  Diff is 0.042 mm (0.0016")
  What is the spec for the Center to Center length and Tol. >>

Those are in fact stock rods for other than Boss-351 engines. Boss rods 
(D1ZZ-6200-A) were simply selected from a batch of rods for length, magnefluxed, 
then shot-peened and hardness-checked. Boss rods got the stronger 'pent-roof' 
rod bolts rather than the standard, weaker 'football-head' bolts. Boss bolts 
interchange in all stock rods and IMHO are a good, cheap upgrade (I use them 
myself), unless you happen to prefer pricier ARP bolts. Otherwise, Ford Cleveland 
rods were all identical. Stock con rods, of SAE 1041 low-carbon forged steel, 
were 5.78" +- 0.010". Three digit-checks are OK. A Tobin-Arp rod-rebuilding 
machine at most good engine rebuilder shops, can correct rod lengths to much 
tighter tolerances than the factory's +- 0.010". And if you're going through this 
much trouble, the piston crowns will need remachining after piston/rod/pin 
assembly, to zero-deck your block. Or, you can do piston-trimming with the rods 
as they are, and simply note the lengths for the next rebuild.
Cheers- J DeRyke