Thread: Should I get poly inserts or brand new motor mounts?

My B13 SE-R needs engine mounts like a mofo. I've never been in a car with so much vibration. I'm a full time student with a part time job and I don't really have the time or tools or experience to take the old mounts out and press the poly inserts in. Is it going to be that big of a difference if I install replacement OE rubber mounts? It would save me the trouble of pressing the inserts in, which seems like a HUGE pain in the a$$.

if you are going to take them out anyways id get inserts..they are probably cheaper..just grease them up nice and good..lol

^ some of the 2 of the inserts are easy the others are a pain.


prothanes are overrated , they dont go bad as fast but you feel everytrhing.

if its your daily driver get some OEM mounts.

Ive had both and i dont think id use them again.

JWT mounts if you can find them are the best .

I havent had insert experiance with the sr20, but on other motors I've had inserts on they always slipped or popped out. The Prothane mounts are a breeze to install, I've had them on my car for a year and a half now with 0 issues as well.

yea, the front and rear ones are easy as hell..havent done the side or tranny ones yet..haha

I disagree with Rodrigo.


The OEM replacement mounts will be at least twice as expensive as Prothanes. The "big squishy liquid filled" OEM mount costs much more (double?) than all four (4) Prothanes combined. IIRC, my Prothanes were $70'ish shipped.

The vibration penalty is a given. You will have more vibrations in the cabin. How much that bothers you is up to the individual, however, it doesn't bother me in the least. Nor did it much bother me before I "stiffened-to-the-extreme" my chassis (IE...before my Restoration, chassis fully-foamed, and every conceivable brace). I rather liked the "connected-ness" to the drivetrain that I felt.

The Prothanes will faaaaaar outlast the OEM rubber mounts. And your tranny/motor will be held in place much firmer, less/no wheel hop, and the tranny/motor does not shift around under extreme g-forces, which gives you better handling (ask Porsche). Less tranny movement also leads to a longer-lasting tranny, no shifting or flexing of the tranny case.

A mechanic shop should not be charging you any more to press-in/install the Prothanes than to press in the OEM rubber mounts. The labor is a wash.

IF you can find them, the JWT mounts split the difference between the Prothanes and the Nissan mounts. However, once again, the price of the JWT mounts is waaaaay more than Prothanes.

id do inserts

I have to agree on the price point but for me drivability is a must , The prothanes suited my B14 well for many years . They out last the OEM ones
2 to1 but that vibration drives me insane. Everyone has prefferences to suit their style .

But as we all Know my friend > We got to pay to play !

Im sure your extra chassis stiffening methods helped you eliminate some that vibration for sure.

in my B14 i could feel tha cabin rattle at a stop lights and under cruising speeds.

My B13 thats in the works has 2 JWT mounts and 2 Prothanes.


another rare set is the OEM Nismo ones but better get ready to give up a left nut if u find them .

Shawn im still waiting for my Cookies recipie man !

Just bought all 4 Prothane poly inserts for less than 70 bucks. Thanks guys.

my polys make the space between my back window and my sunroof vibrate like crazy