DeTomaso Mailing List: July 99, Message #198

Steve,

How to tell????

Numbers numbers numbers.

There may be a tag on the engine that has and engine ID number....  426K or
K428....

But, if the tag is gone, then you must investigate the head casting
numbers, date castings, and equipment...

Boss heads have screw in rocker arm studs, push rod guide plates, spring
cups(??), and closed chamber design.  Unfortunately, the only things that
you can see without actually taking the head or intake off, are the first
three items, and you must take the valve cover off to see this.....

Casting number on the block, behind the starter, may tell you about it. I
believe the Boss's were 4-bolt main blocks in 71. These probably have a
special casting number associated with it.

UNFORTUNEATELY, Ford was not real consistent with their numbers and I have
seen them wrong or such that they are not listed in any documentation....
then you just have to go with what you have.... physically.

Also, check original distributor number stamped in base, ie D1ZE-xxxxx-xxx
and also the Carb number on the small tag or on the front left corner of
the base plate.  THese components were probably unique to the Boss motors
too....

As for all pre-L's being Boss's, this is hard to believe.... DeTomaso
typically ran whatever he could get from Ford... and if he could only get
CJ's then that's what he would do.... but if he got all Boss's then you are
real lucky!  But knowing supply and demand and DeT, I just find it a tough
statement to qualify as gospel..... too risky!

If you can find numbers, I can find the numbers.... in my books!

Steve