74 K member Isolators

[zsn0w]

Hey everyone, I've got a question about peoples' experiences using different body mounts/isolators/k-member mounts on the 73-74 cars. I've found bits here and there on it, but I haven't seen a ton of actual, detailed experiences written about by people using the different options out there. I'm going to be doing a front suspension rebuild soon here, and I'm trying to decide which type to use. Mostly, I've been looking at firmfeel's solid mounts and PST's polygraphite mounts. Also considering trying to get some aluminum ones fabbed up myself, as I have a friend with a mill that I may be able to talk him into giving me some time on if the solids are really that much better, since the firmfeel ones are (in my opinion) crazy expensive for a few hunks of aluminum that all the plans were made for years ago at this point. So, anyone who has replaced these mounts with any of the available options, what has your experience been? What are everyone's thoughts on the different options and their usability for different types of builds? How wide is the gap in feel between the poly and the aluminum? Thanks in advance everyone.

 

[Montclaire]

The rubber ones are being reproduced on a small scale now, too. https://www.ebay.com/itm/Body-to-Su...313105?hash=item4b527a9791:g:evIAAOSwnCFbySDA And there's always the factory cast iron ones (4419942) if you can find them.

I went with poly, the ones with the steel insert. The late B-bodies can be very comfortable cars to drive, no reason to just give that away. Unless you are going autocrossing, the poly will deflect a heck of a lot less than the factory rubber. Don't forget about the torsion bar cross member bushings or the leaf spring pads, either.

 

[zsn0w]

@Montclaire Thanks for the info! I'll probably end up going with the poly, too. I'm hoping it gives me a good mix of more responsiveness and precision without completely getting rid of the comfort of the ride when I'm just cruising.

 

[DemonDave]

Question regarding the isolated rear leaf spring hangers on my '73 Satellite... do I need them? Ha! Can I use earlier springs on my car, or even superstock springs with the long front hangers to mount them?

 

[Ron_M]

I have done 3 cars using the Mopar Performance iron ones. Based on a 1990s Mopar Action article by Rick Ehrenberg. This was before the PST poly and FirmFeel offerings. I've been happy with the outcome. My original s were shot.

I will add that the last car I did, a u code 73 Road Runner, I added the Firm Feel kit to the transmission mount as well.
The ride is tight but harsh and I blame the shitty KYB shocks that I also added. Some day those are coming off.