I'm finally getting to a point where I can start reassembling my Miata project. My new Innovative polyurathane engine mounts were delivered yesterday and I noticed when I test fitted them that both of the mouting points on my subframe are slotted a opposed to having one with two small holes and one with a slot. I have attached pics for clarity (shiny one is my subframe, the dirty one is an image I grabbed from a google search), but my I'm wondering if this is a safety concern. If I ensure that both mounts are sitting at the bottom of the slot will I be fine? Do I need to switch to AWR mounts with the little "pins" at the top and bottom? I just want to be sure my engine isn't going to move around after I bolt it in as it would defeat the purpose of the pricey engine mounts I chose. Thanks in advance for your guidance.

 

You've got yourself a "customized" subframe.

 

LOL

 

Wow. Gotta get me one of them there.

 

So I'm guessing I need to source a new one? Also, I painted because the PO had spilled brake fluid on it and most of the factory finish was gone. I knew this build was going to be a challenge, but I didn't expect to find things like this. I've lost count of things I've had to replace due to the negligence or stupidity of the PO.

 

Is that subframe out of a NB

 

Anything is possible at this point. Lol. But I pulled it off my 97 NA.

 

Just dump it and find a subframe out of a NB. You will also need a NB steering rack but you will be better off in the end.

 

Thanks for tip. New subframe it is.

 

After having done a bunch of engine installs, can sure see how a slot on both sides would have been helpful - genius!

 

Yeah it might save you upwards of 5 seconds!

 

I respectfully disagree. When mated to the tranny, it never once (out of 6 times in last 18 months) dropped down into the hole and slot without going thru the wheel well, and putting on the mounts after the motor was already in place.

 

You definitely need a new one. That one has modulus deficiencies now

In all seriousness, it's probably got other issues (bent, etc) that caused the PO to **** with it. Not worth your time to use.

 

I would probably still use it. Only one of the layers isn’t slotted from the factory.

 

Its fine, You can keep running it. If the previous owner has some shims under the mounts to raise the engine slightly, you have slot the subframe. No strength lost