[DeTomaso] Damper dude
MikeLDrew at aol.com
MikeLDrew at aol.com
Fri Jul 3 23:21:09 EDT 2009
Hey guys,
Had a busy day in the garage today. PCNC member Garry Choate was
scheduled to drive up to my house (about an hour from his home) to help me R&R the
damper and also the front main seal, in an effort to fix a major oil leak
that has plagued my engine since I got it back in 1995.
Turns out Garry called Barry Hosier, another PCNC guy, at his work (he's a
mechanic for BART), and asked him if he wanted to come along? Barry picked
up some papers and walked across the shop with a very determined look on
his face, as though he was on his way to some sort of important meeting, and
kept on walking right out the side door, FOOM! He was in the wind!
Garry's beautiful red Pantera L pulled up to my house with the two of them
inside, and we got to work. I'd already pulled the center console, engine
cover etc. so it didn't take very long for us to get the pulleys off and
pull the old damper.
This project was instigated by the fact that my car ran like crap on the
way to Reno, seemingly on about 6.5 cylinders, slow as hell and rough too.
In the parking lot, John Taphorn and the tech team discussed it and suggested
that it might be a timing issue, and just arbitrarily spun the distributor
and cranked a bunch more timing in. Turns out that improved the car's
running immensely, leading me to believe that my damper ring had slipped and I
had therefore been setting the timing incorrectly.
So, we pulled the old one, which looked to be in absolutely perfect
condition, then compared it with the new one by lining up the keyways. The
markings were identical. So much for the slipped ring theory.
We then inspected the front of the engine. There didn't appear to be an
oil leak from the front main seal, but the entire engine and engine bay are
just covered in oil mist. It appears that the engine builder failed to use
a gasket on the front of the oil pan and instead just relied on RTV, and
that RTV feels rather squishy, so it's possible that my front main seal problem
is in fact an oil pan seal problem. On the other hand, those are both
from low-pressure areas, and my engine pumps oil out at high rpm (it left a
one-foot diameter oil puddle on the engine dyno after two pulls). The filter
is nice and tight, and the oil pattern seems to be coming from the front of
the engine somewhere. Ages ago I thought it was from the front of the
intake, but it's nice and dry up there, which is what then led me to think about
the front main seal.
We'll see.
Since we were there, we changed the front main seal (astonishingly easy,
and ironically Garry had brought a new seal with him, and then I found an NOS
Ford seal in the original box in my huge NOS parts stash that I *still*
haven't had time to inventory yet), and installed the new damper. It's clearly
a quality part, and both Barry and Garry found themselves suffering from
Damper Envy. :>)
Garry had a tool that threads into the spark plug hole and lets you find
TDC easily, and after using that, we found that the markings on the new damper
(and the old one) were only off by one degree. We used a paint pen to mark
TDC on the damper (and damn, now that I think about it, we were going to
mark the flywheel but we forgot!), and then rigged up a timing light to see
what the distributor timing looked like.
Would you believe that after JT spun my distributor, this motor now has
*24* degrees of initial timing, and 42 degrees of total timing????
I didn't either. I figured Garry was screwing something up with his
newfangled dial-back whippy-dippy timing light, so we set it aside and pulled out
my old-school Flashomatic 2000, that has no buttons or digital
displays--just a light and a trigger. Sure enough, initial timing was 24 degrees,
total timing 42 degrees.
And yet the car happily starts with no effort even when smoking hot, and it
runs great, without any detonation or anything else untoward. It just
doesn't have a ton of power.
We thought about the situation and convinced ourselves that the camshaft
must be installed retarded as opposed to straight up. This drops cranking
compression since the intake valve is open longer, during the compression
stroke, and would explain why an engine with 24 degrees of static ignition
timing can still start easily. Retarding the cam timing reportedly also hurts
low RPM power, which is a problem on my engine. On the other hand,
supposedly it helps power at higher RPM (where I don't need it).
After considering the situation closely, we decided to just button the
front end of the engine up and leave well enough alone. After a bit of horsing
around (checking for vacuum leaks around the intake, none found, and
changing a duff carb/air cleaner gasket), we took the car for a spin.
It seems to run great, and for sure it has much more oomph since the timing
was advanced some 10 degrees or so while up in Reno. It pulls reasonably
well from 1500 to 6000 rpm, with no hint of detonation or any other untoward
behavior.
When we got back to the house, I took Garry's Pantera for a drive. It's
got a stock-ish bottom end with a bit of a cam (with the emphasis on
midrange), Edelbrock heads and an Edelbrock Performer 2V intake, and a 650 Holley.
He had a lot more valvetrain noise, and the power delivery seemed more
linear than mine, but it wasn't MUCH faster than my car is--and my Pantera has at
least a couple of hundred pounds of extra weight in the form of thicker
steel for the floorpans/rockers, iron heads, and dynamat out the wazoo.
As it was 97 degrees outside by this point, we decided to call it a day.
So, I can add a lightly used stock Pantera damper in excellent condition to
my parts-for-sale pile, and start thinking about my winter project. Do I
tear the front of the engine off, reset the cam timing (I have a Pete
Jackson gear drive) and install a more suitable cam, in the hopes of developing
proper power? Or do I go for broke and build a monster 408 stroker with
aluminum heads and transform the car into a real rocket?
Decisions, decisions....
Mike
**************
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