Just
a note, I believe poly is resistant to oil, more so than rubber, rubber
that just falls apart on non pristine engine; this can matter ----a lot.
A person with Chem E background may comment more on that.
second
, they squeak like crazy , including “polygraphite”; which is
a marketing recovery term. ; I used them in a 67 Cuda 273 convert
suspension , liked the stiffness, but hated the squeak. Used also for sway bar
hangers where stiffness helps, but sounds like mice under there. I believe they
were removed for rubber due to noise.
I
think they should be great for motor mounts and tranny mounts . Ever look at an
old K frame end , torsion bar rubber swivel bushing? Usually takes a set
off center ~ ½” . One clue, tire hits inner fender when backing up on
sharp angle turn. As alignment is, er, not there. But I guess smooth ride....
Have
used the Schumacher bonded A block mounts that sort of rewrap in so they will
not shear off at a bond. I liked those.
Imperial
is a great source; period.
Ya
take yer pix.....my .02
John
Grady
PS
Bob , be super extra careful to really take the steering box bolts to frame to
their rated torque on your A body, and use high grade , best bolts . Ask
me (and Jamie Hyde) how we know. Called the Route 90 lane jump . Every time a
truck drafts by you. Yet all steering linkage new and tight. Jamie spotted
whole box moving slightly after 4 th time on a lift . Sounds crazy but true .
These were front end mechanics....And you do need those leaf spring
wraps, or equivalent , or springs will splay out. . A prior owner tossed
them.
One
more PS, those clear round dials on 67 cuda dash can push in about .060 and
mechanically hit gauge needles driving you crazy, the gauge is not bad, it is
putting the cover on! Glue clear part to backing while apart!
Car
is great now.....!
Mike et al,
I am familiar with the concerns about substituting
polyurethane front end components in place of OEM rubber originals and have
heard and read of others finding the ride objectionable after rebuilding a
front end using aftermarket polyurethane parts. In fact, that is
the reason I went with original OEM front end components in the A body
Barracuda project I have in my garage.
Having written that, I am at a loss to see how that would
translate to the same concerns regarding engine mounts. As an example,
about 10 years ago, John Hertog wrote a piece for our 300 website tech section,
(I think it is still there) about repairing a failed engine mount, by making a
"Franken mount", that is, drilling through the broken rubber mount
and securing it with a bolt, through the steel into the failed rubber, and back
out again thereby allowing the original mount to be placed back into service.
I emailed him with questions about the fix, and asked
whether there was any noticeable vibration from the engine transferred to the
frame using the Franken mount, and he replied back that he could not notice any
difference. Based on this feedback, my thinking was that since he did not
notice any difference with his solid, bolted mount, that a poly mount
substituted for a rubber OEM mount would have little to no affect.
Anyone on the list have the poly mounts from Imperial
Services installed on their car? Did you notice any difference?
Another question, if poly is a concern, does anyone know of a service that
revulcanates OEM mounts with rubber? As a consultant for the Inc. Club I
get calls from individuals dealing with failed motor mounts, and have been referring
them to Imp Services. Recently, a high school friend of my daughter asked
me for help finding mounts for the '63 Imperial he inherited from his
grandparents, and I sold him my spare mount set to help him out as the repops
are pricey.
Bob J
From:
Michael Moore [mailto:mmoore8425@xxxxxxx]
Sent: Wednesday, February 12, 2014 6:04 PM
To: Bob Jasinski
Cc: 300
Subject: Re: [Chrysler300] 300G
I
have restored several British sports cars. Polyurethane bushings in all sorts
of colors are sold by major parts suppliers, and people love them because
"they're stiff" and " they're tough". There is nothing
wrong with them. I just prefer not to use them for a subtle reason.
1.
Several years ago, Sports and Classic Car Magazine (I think) had a cover
story abut a comparison between two MGA's, both of which were on the cover. The
cars were identical even to the light blue color. One car was totally original
and very low mileage, around 30,000 miles as I recall. The other car was
freshly restored using modern materials and parts but still authentic.
Two writers left in the two cars for a weekend.They drove a day to the other
part of the country, overnighted, then swapped cars the next day for the trip
back home. They then compared the cars and wrote about it. They were unanimous
that the original car was superior in every way, especially handing and ride.
The fresh restoration was very stiff and harsh riding, and not as comfortable
for a long trip. It was attributed to several things but one major one was
polyurethane bushings and body isolators throughout.
I
also had a friend who worked at a British sports car factory and he once
mentioned how much trouble the engineering department went to determine
exactly what hardness rubber to use in various bushings, They would take it to
the test track, record data, then spend time removing softer bushings to
install higher hardness bushings or vice versa. A lot of engineering time was
spent to get everything as it should be.
Likewise,
I personally designed some very large industrial isolators many years ago. I
started with something like 85 Shore B hardness, tested, and went to 80 and
tested. I eventually selected the exact hardness needed for my application. I
have never seen any hardness specification on any isolators and would not
expect anyone to ask or answer-like I said, its subtle!
Finally,
I restored a 63 E Type a number of years ago. It used OEM or NOS parts wherever
possible and no polyurethane in any of the bushings or isolators. It drove like
a dream. Then, my son asked me to restore one for him, which I did-but he
wanted all the boy racer stuff. Competition shocks, nice red poly bushings ,
etc. So for a year, I could drive either car as I finished up his car.
I
would not have realized how horrible his car was had I not been able to drive
my car also. It was a different car-but it was very stiff, and he loves it!
That's
my opinion, and there is nothing wrong with poly bushings. They are tough.
Michael,
That's bad news. I just let a spare pair of
originals go because I thought I could always get new ones. I wonder how
wide spread the problem is, polyurethane is very popular for front end
parts. Any others on the list having a bad experience with the
repro's? What does Imperial Services have to say? Warranty?
Bob J
From: Michael
Moore [mailto:mmoore8425@xxxxxxx]
Sent: Wednesday, February 12, 2014 4:25 PM
To: Bob Jasinski
Cc: 300
Subject: Re: [Chrysler300] 300G
Bob,
Thanks
I prefer not to use polyurethane, I have a used floating power poly mount now
which is separating, I'd like to find an NOS rubber mount, or a good used one
if possible.
Michael,
Have you tried this vendor?
http://imperialservices.net/imps.html
Bob J
Jeff
responded to my email today and has been terrific help.
I
need a NOS 220237 left side engine mount though and he doesn't have them.
Mike
Moore
Jeff Carter has
more parts than you can imagine. Contact him at JC Auto Restoration in Seattle.
Google for website and phone number. Great guy; good to work with. He restores
our letter cars to perfection but has warehouses full of parts.
I'm new to the group and the 300 club. I have two
300k's as well as a 300G that I'm trying to bring up to par. Currently
I'm trying to hunt down a pair of inner fender inspection plates for the 300G.
Any info on their potential acquisition would be appreciated.
