Transmission mount development assistance please

A forum for owners of S30 and S130 Datsun Z's... 240Z, 260Z, 280Z and 280ZX!
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Car: 1. 1987 300zx Turbo-swap, SF interior, koni rallisport springs/struts, msa swaybars
2. 1997 Sebring coupe
3. 1987 300zx 2+2 becoming a caged racecar with RB swap...

Transmission mount development assistance please

Postby G-E » Tue Feb 05, 2019 7:00 pm

Kind of a cross-post from ... velopment/ but since I have questions I'd like answered, the more eyeballs the better right?

So the plan is to offer an adjustable poly trans mount for the s30. The kit will be based on the z31 parts, so the only development is really going into the bracket, and sorting out what hardware to include. The mount would be lighter, stiffer, height adjustable, and slotted for a little tweaking. I'm sure many of you are aware of my company but if not you can check out the general product quality and interesting designs for comparison. Adjustability is kind of a mission statement around here...
Firstly, the bushings are offset, putting the majority of compressive material above the bushing sleeves on the 300ZX kit, and like the 300ZX kit, we would be ditching the upper C-shaped isolator that attaches to the OEM bracket which is a lot softer. However, because of driveline swaps, I don't know how much height adjustment would be ideal for a s30's, the bushings can be rotated to a position 8mm lower (4mm offset eye = +4/-4), but shims or washers can be used on top. The 300ZX kit comes with 4mm shims (optionally) but standard washers are approximately 2mm thick, and would be a cheaper option if significant height isn't needed.

The included photos show the potential change on the baseline height, but because the OEM mount sits funny and the upper isolater is deformed, it's hard to get a perfect comparison. If anyone can provide accurate face offsets from the bracket to the isolator top on a new bushing, I would appreciate it.

Secondly, as you can see, the shape would be somewhat different, there is more stuff hanging down to the sides, and less in the middle, I'm concerned this might affect exhaust clearance? Some expert feedback welcome here as well.

Assuming everything checks out, there's a third possible question here: offering plain brackets without the seams welded (as shown), as opposed to welded and powder/e-coated could be an option, what are your opinions on that if it saves money? Likewise, what's a fair price with weld+paint? I've seen some very expensive mounts for engine swaps that are far simpler designs, and I know this can be offered <$200USD...

As for compatibility, the mount uses standard Nissan bolt spacing, and has been shown to work with all the 30a/71c and T-5. Anything compatible with those should also work well, the mount is narrower in body than the rather bulky isolator it replaces.
Thoughts, comments, interest, and importantly answers welcome!

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