Re: [DML] Adjustable Shocks

["Walter" <Whalt@xxxx>]

Mike,

Here are some answers to your questions about PJ Grady's shocks:

The new rear shocks ARE coil-over adjustable. As I said in a previous
message, the lower shock body has 3 grooves where a snap-ring fits. Over
this snap-ring fits a collar which keeps the snap-ring captive and holds the
lower spring cup. The rear height of the car can be adjusted according to
which groove you place the snap-ring into. There are 3 grooves placed about
1/4 inch apart. The highest groove is equivalent to the OEM ride height.
Rob said that he might start having the shocks made with more grooves in
them for people who want to lower the rear of the car more than 1/2 inch,
but it's probably not a good idea to go much lower than that.

Rob didn't say anything about adjusting them other than saying what
pressures they were supposed to run at. He told me that they already had a
relatively light charge in them, yet they were more firm than typical
aftermarket shocks. Based on that, I figured that I wouldn't want to be
adding any more charge to them anyway, so I didn't ask how.

Since the charge of nitrogen in them has such a high pressure and low volume
as compared to what you would find in a car tire, I think it would be
inappropriate to use a tire pressure gauge on them. These aren't anything
like leaky door struts. They will keep their charge over time. And if they
ever fail or wear out (however unlikely) they are rebuildable.

I've noticed already that the car handles better. At first I just noticed
that the ride is less bumpy. But with more test driving I've found that the
rear tires stick to the ground better. Sometimes I like to take fast
U-turns. If I do it on a bumpy road, the rear tires loose traction and the
car over steers. This can be really convenient when you want it to happen
and it happens the way you want it to. But I'd just assume have the rear
tires not come loose so easily. These new shocks do a better job at keeping
the rear tires planted on the road. I think that the OEM shocks are so
stiff that they are as reluctant to elongate as they are to compress. Once
compressed, they stay for a microsecond too long allowing the tires to loose
traction.

I'm looking forward to getting the new shocks and lower springs installed on
the front to see what more improvements I get in handling.

I would have changed the rear shocks sooner, but until I heard of PJ
Grady's, I haven't seen a design that I really liked.

I considered Byrne Heninger's kit. It is basically a metal pipe which is
large enough for the shock to fit inside of. It has holes in the bottom
which take the same bolt that holds the lower shock. The kit requires a
longer bolt and spacers to make everything fit (which it comes with). There
is a metal flange welded to the top of the pipe which provides a seat for
the spring cup. This design allows you to use any aftermarket shock that
will fit inside of the pipe. And the pipe is big enough to take the top of
the line Monroe unit which Byrne recommends. He was very emphatic about how
good it is to get the weight of the car off of the shock body -- which this
does. This kit is not adjustable. You buy the version of the kit that is
made to put the rear ride height were you want it. After that choice is
made, there is no more adjusting the height. A disadvantage that I saw (or
maybe thought that I saw) was that there was nothing to keep the spring cup
from sliding sideways except for the force of the spring and the weight of
the car. There is probably enough weight on the cup to keep it from moving,
but since both Marty's and PJ Grady's designs as well as the OEM design has
a flange that fits inside the cup to stop it from moving laterally, I didn't
like seeing Byrne's design neglect this. Another point that worries me
about this design is that it is wider and requires a longer bolt to hold it
to the car. This longer bolt will put more stress on the rear hub carrier,
but I am not qualified to say whether or not it is a safety issue.

Another solution that I considered was Marty Maier's. I consider it the
next best thing to PJ Grady's and it is also less expensive. His uses a
clamp that fits on the lower shock body and is very adjustable. The
disadvantages, if any that I can tell, is that the weight of the car is
riding on a shock body that wasn't intended to hold that kind of weight.
Before Marty starts yelling and screaming at me, I'll have to say that I'm
sure the shock body is sturdy enough to hold the weight anyway. If it's
strong enough to be a shock body, then it's probably also strong enough to
hold the weight placed on it by Marty's clamp. Marty's design relies on
friction to hold the clamp in place. It seems that the clamp could slip if
it were jarred hard enough, but he makes it with a good amount of surface
area to hold. Also, I have heard of nobody having any problems with this
setup. If you ever had to replace the shock, you would have to use one with
the same lower body diameter to fit the clamp properly. If you want to
lower the rear of your D and you don't want to pay the higher price for PJ
Grady's product, then Marty's is the way to go. Marty once made the comment
to me that the OEM shocks are so stiff that they might as well have used
steel rods. I agree!

After seeing both Marty's and Byrne's design, I was ready to make one of my
own. My design was going to be a hybrid of both of these. I would have
used the pipe idea like Byrne did and then use a slip collar over it like
Marty did. For the slip collar, I was going to start with a pillow block
(as used to hold a bearing) and machine the inside enough to fit over the
pipe. I would also cut a lip in the top to fit a little inside of the
spring cup to keep it from shifting laterally. Since pillow blocks were
only available in cast iron, I would have had to make something from
scratch. But then Rob seduced me with his 'custom made from scratch
specifically for the Delorean' shocks. I just had to have a set. And I
bought these after I already had a new set from NAPA ready to put on the
front.

Walt Tampa, FL
-----Original Message-----
From: Mike <mquinto@xxxx>
Date: Sunday, November 19, 2000 9:24 PM

>I wonder who makes them for Rob?
>Did Rob say anything about adjusting the shocks yourself. Or needing
>to buy a shock gauge.
>I do know by experience that if you do not use a heavy duty valve
>cores they will leak over time.
>
>Does anyone know if he plans on making coil-over adjustable shocks.
>I really would be in the purchasing mode for them.