Mike,
Here are Dave Tietz' plans, posted on this list previously by Andy Ramm.
Dan
-----Original Message-----
From: Andy Ramm <aramm@concentric.net>
To: mgs@autox.team.net <mgs@autox.team.net>; madamson@compuserve.com
<madamson@compuserve.com>; ctp@gbn.org <ctp@gbn.org>;
peloquin@mamba.bio.uci.edu <peloquin@mamba.bio.uci.edu>;
davew@moldmastersintl.com <davew@moldmastersintl.com>
Date: Friday, January 09, 1998 9:52 AM
Subject: Rear Tube Shock Conversion Plans
Greetings all,
The following is a post from listmember Dave Tietz on rear tube shock
conversions on MGB. This is an excellent post and many thanks to him for
the
information. I take no responsibility for the contents of the post. What
you
do to your car is what YOU do to your car. That being said, here's the good
stuff.....
Andy
>>>>Andy, I went through it all last winter, and here is my fix...
Rear Tube Shock Conversion 02/28/97
Background: I wanted to "modernize" my MGB-GT's suspension with gas
filled tube shocks, and after doing some shopping, decided on the
Moss-Monroe front & rear kits. After installing both sets, I discovered
that the rear shocks were way too hard (the shocks are from GM 1/2 to
3/4 ton vans, front suspension). The front shocks seem OK.
After a frustrating 6 weeks talking to Moss Technical, I was able to
return the shocks to the dealer. Moss was nice enough, but I don't think
they really understood the severity of the resulting ride, or they
didn't get enough complaints on the product (although I know of several
besides me). I kept hearing "Its a competition product", or "The
stiffness makes for better handling", neither of which I can accept. I
have ridden in several Porsches & Corvettes, none of which was as teeth
jarring as my shocks.
I did some research on my own (shock absorber books are a closely
guarded secret with most dealers & parts houses for some reason). One
friendly dealer, a local Tire Kingdom, let me spend about 3 hours with
their book, and I was able to find shocks that have an acceptable
compressed dimension, a longer extended dimension, suitable mounting
bushings and are designed for a similar weight vehicle. The conversion
does not require modification to the car (other than relocating two
parts) and uses existing mounting holes.
The Conversion:
Disclaimer: This worked for me, on my MGB-GT, and appears to be working
well after 6 weeks. This is for your information only, and you are
warned that if you attempt this conversion, you do so entirely at your
own risk. Sorry, but in this litigious age, I want it understood, I
ain't responsible for nothing ˜ Dave Tietz.
Parts needed (about $40.00):
2 2 1/2 inch long, 7/16 fine thread Grade 5 or better bolts.
2 5 1/2 inch (6 inch will work) 7/16 fine thread Grade 5 or better
bolts.
4 7/16 fender washers.
10 7/16 flat washers
4 7/16 lock washers or use locking nuts below.
4 7/16 nuts (or locking nuts).
2 Monroe Sensi-Trac 5877ST Shock Absorbers or equivalent. These are
from a 1984-1988 Dodge Colt (and may be used on other cars).
Procedure:
1) The old lever-action rear shocks are removed.
2) The Shock Brackets (bottom-most plates, clamping the rear-end tube to
the springs) are removed, flipped over (so the hole points down) and
replaced on the other side (left one on right side, right one on left
side) so the hole is still on the inside, but the bend is down, instead
of up. Re-torque the four U-bolt nuts securely.
3) With the 5 1/2 inch bolts, bolt the top of each shock in the
forward-most old shock mounting hole. Use the fender washers on either
side of the "frame", bolt head in the wheel well. The shock bushing, a
flat washer, lock washer & nut on the inside of the frame.
4) To be safe, I measured the distance of the Bump Plate (on top of the
axle, and the Bump Rubber, and found it to be 4.1 inches (I have new
rear springs). I then measured the distance from where the bottom of the
shock mounts (the hole that was moved from up to down, in step 2 above),
to full compression of the shock, and found that to be 4 inches. As the
shock is mounted at an angle (and will not compress inch for inch to the
vertical distance between the Bump Rubber and the Bump Plate) the shocks
cannot bottom out. It would be good to double check your vehicle.
5) With the 2 1/2 inch bolts, bolt the bottom shock mount through the
hole (if it is "wallowed out", from years of movement by the old shock,
you can drill a new mounting hole to the rear of the original hole ˜
which gives even more clearance to bottoming-out). The new hole should
be a clearance hole for the 7/16 bolt, like 15/32 dia.. Use washers on
either side of the shock bushing, and lock washers/nuts or locking
nuts.
Torque the bolts securely, I am a fan of Lock-Tite, and used it
lavishly, both in re-bolting the U-Bolts and shock mounting bolts.
Make sure no other components are near the shocks, like a previous
owner, re-routing the fuel line, or wires or anything that might cause
wear or failure of a part. On my car, they were clear all the way
around.
As noted above, this is about a $40.00 conversion, and I believe the
Sensi-Trac to be superior to the 1920's technology Lever Action shocks
(and more closely matched to the MGB than the Moss kit).
For Your Information...
Dave Tietz
Afterword:
The conversion has now been on the car for 8 months, and seems to be
working beautiful. This car is my daily driver, and we are at about
7,000 miles.
Good luck,
Dave Tietz
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