Stock OEM engine/motor mounts or polyurethane

[jjrock5]

So my 2g GSX 7 bolt will be equipped with the FP Green as well as ALL supporting mods. It will be running 22 lbs of boost.

As much as I'd like to say it will it will probably rarely see launches as it is a daily and I don't launch now.

What I'm asking is do you recommend NEW all around OEM engine mounts (these will obviously be more solid than the old stock ones now) or going polyurethane all around?

I already have SOME vibration as the balance shafts are removed so I don't want anymore.

What do you guys think?

 

[92AWDHX40]

Ill never do oem again i have inserts they were cheap and my buddy popped them in. Love them. I had them in before i rebuilt my engine last year, and after the mounts cant tell the difference. It may shake a bit but not from mounts.

 

[Dsmj89]

go polyurethane all around, the added vibration isn't even that big in my opinion, some people are a little on the soft side .

 

[92AWDHX40]

Yep its not a luxury car kinda funny when it does rumble at stop lights, love it.

 

[jjrock5]

Well I'm building my car for comfort and performance and please don't say you can't have both.

Oh and it's not about being soft more of not feeling like you're driving a damn drag car when youre going to work. That sh!t gets irritating after a while.

Who knows, Im still on the fence. I've had both so I know what both can do.

 

[mindset]

Well if you're looking for comfort install OEM ones. I myself am putting in the polyurethane ones.

 

[Calan]

Weird.. just posted this in another thread.

Well I'm building my car for comfort and performance and please don't say you can't have both.

Oh and it's not about being soft more of not feeling like you're driving a damn drag car when youre going to work. That sh!t gets irritating after a while.

Who knows, Im still on the fence. I've had both so I know what both can do.

I can totally relate.

I wanted a firm and solid mount, but I also didn't want my mirrors and teeth rattling around loose in the car. You may want to look at this (about half way down the page), if you are considering the Prothanes.

 

[Project2G]

I put in prothanes a few months ago and don't know why I didn't do it sooner, like a few years ago.

 

[92AWDHX40]

Well i like mine was unsure at first but they feel about the same as oem, but thats my opionon on my car.

 

[jjrock5]

Weird.. just posted this in another thread.




I can totally relate.

I wanted a firm and solid mount, but I also didn't want my mirrors and teeth rattling around loose in the car. You may want to look at this, if you are considering the Prothanes.

Hmm I like the logic in this, I was contemplating something like this a while ago but never experimented it. I'll keep that in mind. Thanks!

 

[Calan]

I think the Prothanes are hit and miss. I've ridden in some cars with them that feel just slightly firmer than stock, and then there are cases like mine where it might as well have been a solid welded mount.

 

[brownfinger]

Weird.. just posted this in another thread.




I can totally relate.

I wanted a firm and solid mount, but I also didn't want my mirrors and teeth rattling around loose in the car. You may want to look at this (about half way down the page), if you are considering the Prothanes.

Thanks man. I just stumbled upon this. It's good to find info that you need, when you need it. Awsome looking car, too. Thanks

 

[jjrock5]

So I just went on CAPS and used an online Mitsubishi Parts dealer and it would cost me approximately ~$196 to get all new oem mounts (w/ brackets) for all 4 corners.

If I were to get Prothanes, I would pay ~$70 for the kit and ~$40 for the install (if I were too lazy to press them in myself). So that comes to a total of ~$110 to get polyurethane mounts.

As always, money is an issue so that'll play a big factor when deciding which to get.

 

[TuRBoTaLooN]

Here's my opinion. Get the insert set. Only install the front and back inserts. You don't need to press out the old ones and press in the new ones. These inserts just go over the OEM stuff. See how that feels. If you want stiffer then do the trans mount and driver's side motor mount. Those need to be pressed out. You can pop them in with a mallet.

I also like the idea of drilling the holes through the poly mounts.

 

[jjrock5]

Well actually I had only the front and rears on my 2g GST and i didnt feel ANY difference. The engine still managed to dance around in the bay. At that point, it would've been better to get new oem mounts since polys had done nothing for me...

 

[romeen]

I think the Prothanes are hit and miss. I've ridden in some cars with them that feel just slightly firmer than stock, and then there are cases like mine where it might as well have been a solid welded mount.

Craig, that's a great idea. Glad to hear of the great results. I am going to try that. I wish I had your equipment.

jjrock5, if you want the performance benefit without the vibrations then I suggest you do the inserts for the front and rear and leave the side mounts alone. I have tried:

1) Inserts front and rear with stock side mounts. Provided some benefit (decreased wheel hop) with no increase in vibrations. Keep in mind that I used the Energy Suspension inserts which uses a softer polyurethane so the Prothanes may give a better result.

2) Inserts front and rear with Windo-Weld method on sides. Not a significant difference performance wise compared to above but big increase in felt vibrations.

3) Solid aluminum front/rear with Windo-Weld on sides. HUGE improvement in performance but car vibrates significantly at idle and entire chassis shutters during clutch engagement. When cruising I don't feel the vibrations. Completely eliminated wheel hop (FWD) and enhanced handling.

I haven't tried solid front/rear with stock sides but I have a set of unmolested side mounts here that I am eventually going to install to see what that does.

In summary, the front and rear mounts are the most important as far as performance goes and the side mounts seem to transmit most of the vibrations.

Craig may have found a way to have our cake and it eat too.

 

[jjrock5]

Craig, that's a great idea. Glad to hear of the great results. I am going to try that. I wish I had your equipment.

jjrock5, if you want the performance benefit without the vibrations then I suggest you do the inserts for the front and rear and leave the side mounts alone. I have tried:

1) Inserts front and rear with stock side mounts. Provided some benefit (decreased wheel hop) with no increase in vibrations. Keep in mind that I used the Energy Suspension inserts which uses a softer polyurethane so the Prothanes may give a better result.

2) Inserts front and rear with Windo-Weld method on sides. Not a significant difference performance wise compared to above but big increase in felt vibrations.

3) Solid aluminum front/rear with Windo-Weld on sides. HUGE improvement in performance but car vibrates significantly at idle and entire chassis shutters during clutch engagement. When cruising I don't feel the vibrations. Completely eliminated wheel hop (FWD) and enhanced handling.

I haven't tried solid front/rear with stock sides but I have a set of unmolested side mounts here that I am eventually going to install to see what that does.

In summary, the front and rear mounts are the most important as far as performance goes and the side mounts seem to transmit most of the vibrations.

Craig may have found a way to have our cake and it eat too.

I just looked on ExtremePSI, does Prothane sell JUST the front and rear inserts?

I saw the whole kit but not separate. I know Energy Suspension sells just the front and rear.

 

[romeen]

I just looked on ExtremePSI, does Prothane sell JUST the front and rear inserts?

I saw the whole kit but not separate. I know Energy Suspension sells just the front and rear.

According to their website they do although I've never seen them.

Front inserts: 13502
Rear inserts: 13504

Prothane Applications

But based on calan's results I would seriously consider doing what he did.

 

[jjrock5]

I think I found some. About $40 for the front and rear shipped, not sure if they do combined shipping.

Front:

95 96 97 98 99 MITSUBISHI ECLIPSE Prothane Motor Mounts 13-502-BL

Rear:

95 96 97 98 99 MITSUBISHI ECLIPSE Prothane Motor Mounts 13-504-BL

 

[Calan]

Well actually I had only the front and rears on my 2g GST and i didnt feel ANY difference. The engine still managed to dance around in the bay. At that point, it would've been better to get new oem mounts since polys had done nothing for me...

I notice something similar on my car, but it's because on the 1G's the rear mount is a solid insert like the sides...and with that one in the rear, the little hard plastic "covers" on the front mount make no difference whatsoever.

The rear insert was a super tight fit and binding in the cradle also, but in the interest of getting the car on the road I pounded it down and left it. As soon as I have a reason to remove parts and get to it (tranny swap?), I'm going to pull it and machine it like I did the driver's side mount.

 

[95blackGsTurbo]

Solid aluminum front mount, rest OEM. Get the benefits of the motor staying solid during launches and pulls while the comfort of having an OEM rear mount (that's the one that causes cabin vibration).

 

[99cliprs]

I have the polyurathane mounts and I cant stand them! right around 900 rpm the steering wheel vibrates rapidly my third brake lights smacking the glass.. is it possible they are in too tight or is that just normal? and where can i find side oem mounts?

 

[jjrock5]

I have the polyurathane mounts and I cant stand them! right around 900 rpm the steering wheel vibrates rapidly my third brake lights smacking the glass.. is it possible they are in too tight or is that just normal? and where can i find side oem mounts?

Driver side: MB911270

Passenger side (manual tranny): MB911272

And I just got me all 4 new mounts from rockauto.com for $97 SHIPPED. Their not OEM but same quality. I did the math for OEM ones and they came to about $170 plus shipping if you want OEM.

Screw "better response and less engine movement with polys" Im gonna be ridin like a Cadillac.

I may do front and rear inserts though.

 

[shockracer]

I did the race poly inserts in my 95 neon (front, and both sides) there were 2 different types when i ordered mine Street insert and Race insert. those Race inserts vibrate so much it's can be crazy at times but, i do like the feel of the engine in my hands and a$$, More power for the butt dyno.

 

[DashLaflash]

Does anybody know how much more vibration is increased with the prothane suspension pieces, after the engine mount inserts are installed? I have all four prothane engine mount inserts and deleted the balance shafts but have not driven my GST yet with these installed. I'm thinking I will be able to handle the vibrations. I'm assuming if I can handle the vibrations from the engine mounts, adding the suspension pieces wouldn't be that much worse and I would have a more solid front end.