Are there engine mounts that dampen vibration?

bennylava

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Just something I've been curious about for awhile, I don't actually have any problem with engine vibration. It seems like engine mounts would be the primary way that vibration from the drive train was transferred into the car. So I was curious if it were possible to change out the engine mounts, perhaps to some with thicker rubber (or something). So the driver would experience a "nicer" ride.

Maybe this effect is achieved simply by replacing worn out mounts? Or maybe there really is a way to upgrade them to further reduce vibrations. I admit that I haven't looked at the 95 mustang GT engine mounts in a very long time. I can't remember exactly how they're built.

If I found out that this was a real thing, I'd do it to my old chevy truck too.
 

96blak54

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Over time the rubber of the engine and transmission mounts get hard and almost brittle. Just change out to a new set would make a difference. I dought itll eliminate all the vibrations, but would help reduce for sure
 
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bennylava

bennylava

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Over time the rubber of the engine and transmission mounts get hard and almost brittle. Just change out to a new set would make a difference. I dought itll eliminate all the vibrations, but would help reduce for sure

Would this be a difficult task on a 94?

Any chance for an upgrade to a different kind of mount, that reduces vibration even further?
 

96blak54

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Im not familiar with a 302 small block version sn95 mustang to accurately answer if ease of swapping motor mounts is simple. I mess with the bigger version modular engines which is not an easy replacement. The small block engine 5.0l does offer more wiggle room than a modular engine. You almost have to remove the modular engine to swap engine mounts.

Someone with experience in your situation will chime in and give you some direction.
 

duh09

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The OE style mounts are going to be the best for keeping NVH levels down. Any “upgrade” mount is looking at it from a performance level and generally more performance in those areas means more NVH because the rubber is stiffer, or it’s a solid mount that doesn’t have rubber at all. Game plan there is to reduce the amount of wasted energy in allowing the motor to “twist” inside the mounts and get that power to the ground. So the OE softer mounts are the better option for what you’re talking about.

Changing motor mounts on a 5.0 car isn’t super hard, but can be a bit annoying. There’s one side that you need to get jacked up a bit more- I think the driver side because of the steering shaft- just to get the Mount into place easier but I swapped to solid mounts as a 17 year old kid who probably shouldn’t have been turning wrenches in an afternoon.

If you decide to swap your mounts, don’t forget to swap your transmission Mount too. Fresh mounts should just about kill any engine vibration you’re feeling. Also, check your engine balancer. They’ve got a rubber section that is notorious for failing and a piece worn or missing will cause a vibration. A failing balancer is partly why I swapped to solid mounts back in the day, only to realize the problem was the balancer the whole time.
 

Mustang5L5

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Lower durometer rubber mounts would be the answer, but I suspect longevity would be diminished. Options are limited to rubber mounts these days anyway as the OE mount is NLA as far as i know.

I put poly mounts in my 5.0 and it definitely transmitted a bit more vibration to the chassis. Car feels more raw, but definitely more NVH
 

Daryl

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I think deteriorated mounts can also slightly affect driveshaft/pinion angle which can possibly add to vibration. So I’d definitely have to agree that, in your case, stock rubber motor and transmission mounts as Step 1. If the vibration still outside your satisfaction level, then the balancer, which is a much harder job but can make a HUGE difference.
 
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CobraRGuy

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I used Energy Suspensions polyurethane engine mounts in my car. They still allow some flexing, but they do transmit more NVH (Noise Vibration and Harshness). My car is already pretty brutal to drive, so solid mounts are not on the table for me.
I have a set of SN-95 convertible motor mounts which are a different part number and supposedly a little stiffer than the coupe ones. Let me know if you want them.
 
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bennylava

bennylava

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Im not familiar with a 302 small block version sn95 mustang to accurately answer if ease of swapping motor mounts is simple. I mess with the bigger version modular engines which is not an easy replacement. The small block engine 5.0l does offer more wiggle room than a modular engine. You almost have to remove the modular engine to swap engine mounts.

Someone with experience in your situation will chime in and give you some direction.

Which bigger modular engine have you put in an SN95 car? My old 302 is tired and worn out.

Lower durometer rubber mounts would be the answer, but I suspect longevity would be diminished. Options are limited to rubber mounts these days anyway as the OE mount is NLA as far as i know.

I put poly mounts in my 5.0 and it definitely transmitted a bit more vibration to the chassis. Car feels more raw, but definitely more NVH

Anyone happen to know how long the OE style rubber mounts keep their factory freshness? Maybe you get 30k out of them before they've changed enough to allow more NVH into the car.

I used Energy Suspensions polyurethane engine mounts in my car. They still allow some flexing, but they do transmit more NVH (Noise Vibration and Harshness). My car is already pretty brutal to drive, so solid mounts are not on the table for me.
I have a set of SN-95 convertible motor mounts which are a different part number and supposedly a little stiffer than the coupe ones. Let me know if you want them.

My question has been answered so I may as well ask you about the 351. You have a real Cobra R? If so, what is your experience with the 351? I was considering building one someday to replace my 302. But I'd probably only do that if I could stroke the 351 to be a 427. I'm not sure how viable that is vs a coyote swap though. Since NVH is a concern, the coyote is probably the way to go.
 

Mustang5L5

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Anything rubber has a shelf life. Even if you find some NOS mounts sitting on a shelf for 30 years there has likely been some change to them. Hot or miss depending on environmental conditions

That’s why low mileage barn find cars can be sometimes in such terrible shape with regards to all the rubber components.
 

CobraRGuy

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Which bigger modular engine have you put in an SN95 car? My old 302 is tired and worn out.



Anyone happen to know how long the OE style rubber mounts keep their factory freshness? Maybe you get 30k out of them before they've changed enough to allow more NVH into the car.



My question has been answered so I may as well ask you about the 351. You have a real Cobra R? If so, what is your experience with the 351? I was considering building one someday to replace my 302. But I'd probably only do that if I could stroke the 351 to be a 427. I'm not sure how viable that is vs a coyote swap though. Since NVH is a concern, the coyote is probably the way to go.
Yes, my car is a real Cobra R, #242 of 250. I also used to own #191 of 250 which is the retired Jason Priestley number 46 IMSA GS endurance race Cobra R. I sold that car to Ron Bramlett of Mustangs Plus. The 351 has considerably more power and torque compared to the 302, but there tends to be a little less aftermarket support for the 351 (like intake manifold choices). This is undoubtedly because so many more 302s are hot rodded. To get a 427 you'd need the Boss 351 block or, like i did, the aluminum 351 race block in order to get to a 4.125" bore and 4" stroke. I went with a 4" stroke and 4.132" bore for 429 CID. A .030 overbore 351 with a 4" stroke gives 408 CID.
I have not dealt with the 5.0 Coyote so I don't have much to add there, but I suspect there may be additional issues mechanically and electrically. Having said that, people are doing it successfully.
 
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bennylava

bennylava

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Yes, my car is a real Cobra R, #242 of 250. I also used to own #191 of 250 which is the retired Jason Priestley number 46 IMSA GS endurance race Cobra R. I sold that car to Ron Bramlett of Mustangs Plus. The 351 has considerably more power and torque compared to the 302, but there tends to be a little less aftermarket support for the 351 (like intake manifold choices). This is undoubtedly because so many more 302s are hot rodded. To get a 427 you'd need the Boss 351 block or, like i did, the aluminum 351 race block in order to get to a 4.125" bore and 4" stroke. I went with a 4" stroke and 4.132" bore for 429 CID. A .030 overbore 351 with a 4" stroke gives 408 CID.
I have not dealt with the 5.0 Coyote so I don't have much to add there, but I suspect there may be additional issues mechanically and electrically. Having said that, people are doing it successfully.

What would be the issue with trying to stroke some old junkyard truck 351 into a 427? Next question - In your estimation, is there any way to get a 500 hp 351 that doesn't have considerable noise, vibration and harshness? Maybe I'm stuck with the coyote if I want high power and road manners.
 

96blak54

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You asked me

Which bigger modular engine have you put in an SN95 car? My old 302 is tired and worn out.

Any modular engine is bigger than a smallblock engine and by bigger i mean physically bigger. Not internal size bigger.....just bigass bigger! I opted to shove a 5.4l 2valve in mine, meaning everything for the engine had to be made to fit. I dont recommend swapping in anything other than what factory gave you. However, the coyote swap is a popular one and has crazy amounts of naturally aspirated power thats crazy tame for driving. Keep in mind it is a modular style engine and is much bigger than smallblock engines. You need to completely change everything to fit it.
 

CobraRGuy

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What would be the issue with trying to stroke some old junkyard truck 351 into a 427? Next question - In your estimation, is there any way to get a 500 hp 351 that doesn't have considerable noise, vibration and harshness? Maybe I'm stuck with the coyote if I want high power and road manners.
A stock 351W iron block can (typically) be bored up to 4.030", with the stock bore being 4.000". Using a crank with a 4.00" stroke (3.5" is stock) combined with the 4.030" bore gives 408 CID. A 4.000" bore with a 4.00" stroke gives 406 CID. In order to get to 427 CID you need a 4.125" bore combined with a 4.00" stroke. A 4.030" bore could be combined with a 4.25" stroke, but the rod ratio would cause problems with piston wear. Old junkyard 351W blocks will not support the necessary 4.125" bore size to achieve 427 CID. The Ford Racing 351 BOSS block can be purchased with a 4.125" bore and can be further bored up to 4.140" (I think). Some 351W blocks can be stroked up to 4.25" and bored up to 4.160" which results in 460 CID. The Z-351 block I'm using using supports this, but I chose not to take the displacement that far (the cylinder liners get very thin and ring sealing becomes an issue). I chose a 4.00" stroke with a 4.132" bore to get 429. CID. This gives a very favorable rod length to stroke length ratio for better longevity.
Regarding NVH, my engine is precision internally balanced, so I've been pleased with the level of vibration using the polyurethane motor mounts. Noise is another issue and is largely due to the intake and exhaust setup. Mechanical noise is almost nonexistent with my engine.
 

joemomma

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Pretty sure @white95 went the built 351 route and ended up going coyote. He could probably shed some light on the pros/cons of each setup.
 

b1pig

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Just something I've been curious about for awhile, I don't actually have any problem with engine vibration. It seems like engine mounts would be the primary way that vibration from the drive train was transferred into the car. So I was curious if it were possible to change out the engine mounts, perhaps to some with thicker rubber (or something). So the driver would experience a "nicer" ride.

Maybe this effect is achieved simply by replacing worn out mounts? Or maybe there really is a way to upgrade them to further reduce vibrations. I admit that I haven't looked at the 95 mustang GT engine mounts in a very long time. I can't remember exactly how they're built.

If I found out that this was a real thing, I'd do it to my old chevy truck too.

Typically, the "softest" motor and transmission mounts you can buy will be OEM or OEM replacement. Generally, anything else will be tipping the scale towards performance. Meaning less comfort and isolation.

If you have no clue on the age of the motor mounts in your car... especially if they are original, then it is highly probable that new ones would contribute to a little better feel. This isn't something i'd go out and swap out just because i could, though. It's been a while since i swapped motor mounts on anything, but its typically a knuckle buster, on your back on the ground sort of job. If you live on dirt roads and/or have an oily underside... add that. :)
 

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