jdmsuper7

iTrader: (1)

1st off, I am a poor college student with 2 broken motor mounts from too much auto-x.

I was thinking, instead of spending $100+ for premade mounts, I should make my own.

The basic plan is to get some 95A durometer 3" diameter poly discs from McMaster-Carr ($65), some big long grade 8 bolts from a local hardware store, with some fender washers to match. I would cut the poly into 2 3"ish sections with a bandsaw and then drill the center out to accept the bolt. Hopefully this would come out to $80 or so total plus a bit of labor.

This is still preliminary (notice the lack of hard measurements for the heights and bolts), but does anyone see any major issues with doing this?

edit: will delrin work? Surely less damping, but is 1/2 the price and won't break lol

alexdimen

iTrader: (13)

I used 80A durometer on my FD and it is very stiff. I did a sandwich design, which damps in both directions.

FC motor mounts can be had for the same price or less than a DIY setup. Poly mounts, however, can increase performance.

https://www.rx7club.com/3rd-generation-specific-1993-2002-16/motor-mount-163324/

^ you would obviously have to change thickness to match the FC stock mounts height.

For my FD I used 2 1/8" between the mount arm and subframe and 1" on the other side of the subframe.

So, it went:

mount arm
fender washer (3" wide with 3/8" hole from mcmaster)
2 1/8" poly
subframe
1" poly
fender washer (and a few other 10mm washers to spread force)
nut
jam nut

jdmsuper7

iTrader: (1)

Stock yes they are quite cheap (like $40/apiece from mazdatrix iirc), but my stockers were NEW mid 2004, and have been broken for most of the summer (after 4-5 events total). I think I could do alot better than the $130 banzai wants for theirs. Even if I end up spending $100, that $30 saved is nearly a tank of gas. Remember the poor college student thing.

Also, great link, didn't think to look in the FD forum.

The Shaolin

iTrader: (5)

I just got new competition mounts for like, $65 shipped from eBay.