460 Ford Forum banner

1 - 7 of 7 Posts

·
Registered
Joined
·
3 Posts
Discussion Starter #1
My friend wants to know what is the advantage of this is if any? Or should he just worry about losing weight on the crank counter weights?
 

·
Registered
Joined
·
88 Posts
A wider assortment of cheaper bearings is available. Smaller journal gives slower bearing speed(desireable at HIGH RPM). Reduced diameter allows stroking for more cubic inches. Weight reduction at throws MAY eliminate the need for heavy metal(expensive) when balancing.
 

·
Registered
Joined
·
10,854 Posts
NHRA allows using a PONTIAC rod journal size, (2.250"), so an aftermarket Oliver Pontiac rod can be used. That rod is 6.625" long and most companies sell it either bushed of press-fit for a lighter .980" Pontiac wrist pin.
Most of the advantage is rotating weight but, there is some gains in having less bearing surface speed.
Edit: The NEW engine specs listed by NHRA for this year's "Stock/Super Stock" combinations now allow a 2.200" Chevy journal to be used as long as you also use the NHRA approved connecting rods, (and ONLY the approved rods), in the engine.
They, NHRA), now also allow the use of Cleveland size main journals as long as spacer shells are used in the block in order to use the Cleveland, (or B.B.Chevy), size main bearings.
NO aftermarket block having smaller main bearing specifications.
 

·
Premium Member
Joined
·
1,204 Posts
As stated, less bearing speed, lighter throws, tighter packaging, and it also opens the door to readily available BBC rods.
 

·
Registered
Joined
·
88 Posts
Pontiac rods are great! You can easily pin fit them +.004 to .984 and they are drop in's in 331 and 354 early Chrysler hemis.
 

·
Registered
Joined
·
10,854 Posts
NHRA's listed NEW sizes for the cranks of 385's

Newly listed crank journal sizes are in the NHRA 'Stock"Super Stock" engine specifications for the 385 Ford engine; despite the objections of the Chevy racers.
Now they both can use the same sizes...
 
1 - 7 of 7 Posts
Top