DeTomaso Mailing List: October 99, Message #198

> I'm at the point where I need to make a decision.  I'm putting in the
> Crane
> Hydraulic Roller conversion kit to my latest 351C build.  Originally, when
> I ordered the components (years ago), I got a bronze dizzy gear.
> 
While I have your attention, I'll remind you one last time to find out if
the 
roller cam you've selected is compatible with the Crane adjustable valve 
train kit you intend to use.  The limiting factor with the Crane kit is that

> the open valve spring pressure cannot exceed 320 lbs.  Unfortunately, 
hydraulic roller lifters are heavy and require considerable spring force 
if any RPM is to be turned. 

> To install the kit, you remove the stock valvetrain and chase the rocker
> arm pedestal bolt holes with a 5/16 x 18 tap.  You add Fel-Pro thread 
> locking compound and screw in the new studs, waiting 6-8 hours for the 
> compound to set.  Crane also recommends the top five head bolts be
> replaced
> with 1/2" x 4 1/4" grade 8 Allen head cap screws.  With the rocker arm 
> conversion in place it's almost impossible to put a socket on the original
> head bolts.
> 
> If you decide to go this route, you need to check if your rocker arm 
> pedestals are cut on a 90 degree or dovetail angle.  There is a different 
> part number for each case.  
> 
Typically, you re-use your existing non-hardened pushrods with this kit 
because they use plastic ("Feflon") guideplates.  However, your roller 
cam will likely require different length pushrods. 

> Crane offers both a steel and an aluminum-bronze gear.  I want long life
> and I don't think I'm going to get it from the bronze gear.  
> 
Correct.

> So can I go with the steel gear and be okay?  Is this my better option?
> 
Maybe, maybe not.  Mike Trusty can elaborate but I think his 
steel Crane gear turned to powder.  I don't think it did his motor
much good.  Here's what he had to say shortly after it happened:

"As you have probably heard, I did not complete the SS event.  I made it
about 50 miles.  Heard a slight noise, glanced at the gauges and had NO oil
pressure.

I got home last night and figured out what happened.  If some of you
remember, there was some talk about the new steel distributor gear that
Crane has that is supposed to work with steel roller cams.  Well, it didn't
with mine.

The cam was new and all clearances were checked and double checked.

The motor had about 550 miles on it when the gear turned into powder."

I think Cary was also trying this gear.  You might see what his 
experience is. It can be done.  The OEM's do it but the aftermarket 
seems to have difficulty with steel gears.  I dunno why.

Dan Jones