Muscle Mustangs & Fast Fords – October 2019

SHORT-BLOCK BUILD

To the point previously made, note that the solid bearings fit

into the main caps like this. Also note that the bearings with

the side bearing material (called thrust facings) fit only on

the No 3 main. You can see the outline for the bearing on the

side of the No 3 saddle and bearing cap.

To get the main caps to fit in their tight recesses, we lightly

tapped them in place with this small brass hammer. If they

don’t fit completely flush with the surface, find out why

before locking them down with the main bolts.

ARP bolts are the best in the business, and were used in

place of the original factory bolts. Never reuse main bolts

because they stretch and will not keep consistent torque.

It’s critical to make sure that the connecting rods clear the

bottom of the cylinder bores. With the increased stroke and

long rod length, we had to notch the bottoms of the cylinder

bores in this manner.

Our K1 crankshaft is a beefy piece yet weighs a comparative-

ly light 47 pounds. Before lowering it into place, we cleaned

all of the crankshaft journals and then oiled them up to make

sure that there were no dry, metal-to-metal contact points.

Always use ARP’s Ultra-Torque fastener assembly lubricant

to achieve the proper torque spec with the bolts.

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work for the street/strip plan I had for

the engine. While we had to notch the

block to clear the increased stroke of

the connecting rods, that was really

the only serious modification required.

With my plan to potentially add nitrous

or a supercharger, the additional 16

cubic inches would be exponentially

beneficial with a power adder.”

The move to the larger stroke also

brought about a discussion about rod/

stroke ratios. For the record, rod/

stroke ratio is a calculation determined

by dividing the center-to-center rod

length by the crankshaft stroke dimen-

sion. Most engine builders figure that

the best ratio is between 1.55:1 and

1.70:1 to achieve the best durability and

other engine characteristics.

What Does Rod/Stroke

Ratio Mean to Me?

Quite simply, the lower the ratio,

the greater the side forces applied by

18 OCTOBER 2019 WWW.MUSTANG-360.COM