[DeTomaso] Ignition truble

[Daniel C Jones]

> FWIW Joern, Ford/SVO now sells a steel distributor drive gear for 351Ws that
> I think will fit your roller cam Fontana. They also offer a polymer drive
> gear for steel cams.

The Fontana block takes a 351C cam so a 351C distributor gear is required,
not a 351W.  FRPP and Crane offer steel gears for the 351C/351M/400 (same
as the 429/460).  The FRPP gear is P/N M-12390-J (1.421" OD, 0.531" ID,
for 351C) in the FRPP catalog.  From page 105 of the 2005 FRPP catalog:

"Steel gears are compatible with billet steel camshafts (hydraulic roller
 type)".  Comp Cams also claims the Ford gears are compatible with their
 -8 austempered ductile iron hydraulic roller cam cores (Comp also uses
 the -8 cores for some solid street roller cams but uses steel cam cores
 for race solid rollers).  According to MSD, the Ford mild steel distributor
 gears (as fitted to engines with factory hydraulic-roller-cams) are softer
 than the common ductile iron gears, but harder than bronze.  MSD also
 claims that Chevy uses a harder cam core for it's factory hydraulic rollers
 and uses cast iron gears but that its gears don't last as long as the Ford
 gears. Ford doesn not recommend the gear be used on billet steel solid
 roller cams but some 5.0L racers have used the Ford gear on steel cam
 cores without incident.

Crane has a coated steel gear which they claim is compatible with induction
hardened or carburized steel roller cores, as well as iron flat tappet cores.
Their website refers to them as "specially coated and processed steel
distributor gears using either cast flat faced lifter or steel roller
camshafts".  They list two part numbers for 351C distributors:

 52970-1 Ford V-8 70-82, Boss 351-351C-351M-400 for 0.500" shaft diameter
 52971-1 Ford V-8 70-82, Boss 351-351C-351M-400 for 0.531" shaft diameter

Crane does not recommend the use of their gears on camshafts that have been
previously run with other types or materials of gears. Comp did not recommend
this gear on their -8 cores.  I'm told but have not verified that Crane's
earliest steel gears were made like the Ford gears but their new gears are
different.  We used this gear on a 408C recently with a steel cam (hydraulic
roller) from Crane and I ordered one for my 407 Fontana.

Dan Jones