Yes ,it can be done with the engine in the car . It took me 1.5 hrs this afternoon to change out the rear mount .
I first removed the intake tube from the throttle body to the MAS . Then undo 2 nut that hold the main wire harness bracket ,the top not is easy to get at ,the lower nut is a bitch . This alows you to access the 3 nuts (17mm) that hold the bracket on . There is a 10mm bolt that attaches to the lower bracket ,this must be undone.To get the bolts and nuts on the lower bracket ,put the car on jack stands as high as you can get it . You with need an Impact wrench and a 17mm universal socket to get the 3 bolts and the nut on the bolt through the bushing .it is atight fit so take your time and wear heavy gloves while you do this ,there is an exhaust bracket that you can get a nasty cut from. Both brackets are removed through the bottom of the engine bay .Its a tight fit .
To install the new bracket you have to put both assemblies together and fit the assembly in from underneath the car . Once you have the top bracket on it will have to be tap in from the top over the 3 bolts from the top. Now disconnect the bushing bolt to allow you to put the lower bracket bolts in .Once the bolts are in on the lower bracket you can but the bushing bolt back in. You will have to lift the engine slightly to align the bushing hole with the lower bracket ,then tighten everything back up . Put the intake tube back on your done .
I wouldn't recommend doing this along it's a 2 person job .

 

Did you have a broken engine mount? or did you install high perf urethane mounts?

 

The stock mount wasn't broken ,just upgraded to performance bushings

 

Do you notice any louder noise or vibration? Where did you get the mounts?

 

slightly louder at lower rpms ,I got the mounts from AWR Racing

 

Yes I am talking about the one at the back of the engine down low that attaches near the firewall . The front mount is easy to change as for the side mounts I wont be changing them ,no one make them . Just change the front and rear is enough.

 

I work close to a shop that makes motor mounts for the rice mobile hondas if someone has a P5 mount of the same in a earlier year I can find out what it would cost to produce those.

 

What kind of mounts do they make? It would be nice if someone made solid rubber mounts, as opposed to the too stiff urethane ones available now...

 

How does replacing the engine mounts help out? Just curious as to what the point is?

 

I don't know if anyone else noticed this ,At 100kph i am running approx 300 rpm less. The other noticable differance is how the car hooks up when you push the gas. I find the responce much better with no wheel hop

 

So basically new engine mounts sort of reposition the engine to let it perform slightly better? It seems too expensive to be worth it.

 

Do you know by chance how they are different... solid, liquid-filled, etc? It would be great to be able to replace my P5s mounts with something made by Mazda (I would trust it more than an aftermarket part), but arent MSP parts only sold to people with a MSP?

gcs118... I wouldnt say the new mounts reposition the engine, rather they hold it in place more stiffly during changes in acceleration. Try this for example, if you have a P5, in second gear get up to 20-30 mph hold it steady, then give it half throttle and let go. That bit of hesitation and jerking around on/off throttle is partly due to the soft engine mounts letting the engine move around a bit. Another good example is how the car tends to jerk if your in one gear in slow traffic on and off the throttle slightly. Unless you constantly are slipping the clutch, your gonna get jerked around. Stiffer mounts hopefully would get rid of some of this jerking.

 

I also have installed both motor mounts. the front was cake and only took 5 min. The rear mount took me about an hour with the car in the air. I had to remove the main harness from the firewall (2- 10mm nuts) and what a pain that was. But all in all
I managed to do the whole install under the car without removing anything except the main harness and the rear motor mount cradle (3 bolts).

Pros:
Better clutch engagment
Instant throttle response
no motor mount enduced wheel hop
no more after market intake tube dents or holes from hitting the master cylinder
faster reaction times/ launches
cheap at $120

Cons:
Harsh vibrations
Increased clutch pedal sensitivity
tires chirp easily
hard to install/ need the right tools (air, lift, prybar, tranny jack)

I purchased them from www.protege5online.com and was very happy with their quality. I highly recommend them.

 

I sent a couple of hours last evening trying to remove my #1(rear) engine mount. As you explained, I removed two 10mm nuts from the firewall to release the wiring harness. The problem I ran into was the lower stud that retains the harness is directly over the left rear nut for the mount. I've spent twenty years working on aircraft and am very fimilar with working in tight spaces. I could not seem to figure out a tool combination to get to this nut without cutting off the interfering stud. Additionally, all I had were 3/8" drive tools and ended up breaking my MAC universal joint trying to break the other nuts loose. I'll try again with 1/2" drive tools and try to figure a way around the the lowerr wiring harness stud. Any suggestions and and tool combinations would be helpful. Thanks.

 

it would kick *** if someone would get some pics of the tools, and the process of everything. there has been about 10 people to do instructions over the different forums but no one does pictures.