My $67 sound dampening / undercoating

[CTScott]

I have been meaning to paint the inside of the wheel wells since I bought my Yaris to get rid of the patchy look of some visible paint and some patches of seam sealer.

This Saturday I was planning on doing an oil change and figured I would do something with the wheel wells while I had it up on the lift. Doing a little research on coatings for the wheel wells, I found that Herculiner paint-on truck bed coating seemed to be a good choice. It is a urethane rubber based coating and is promoted as being for both truck bed protection and undercoating. For $67 for a gallon, I figured it was worth a shot. I wanted something that could be brushed on to avoid the mess of overspray.

Herculiner.jpg


I initially applied two coats to the wheel wells. I then got under the car and coated the floor pan. This morning it was done curing, so I took it out for a test run. The roads were wet and coated with sand from Saturday's snow storm. I was extremely impressed with the sound dampening that the coating provided.

Yaris - Undercoating.jpg

Yaris - Undercoating2.jpg

Yaris - Undercoating3.jpg

[Altitude]

Nice. Very jealous of your lift.

[fnkngrv]

Additional weight?

[CTScott]

Originally Posted by fnkngrv

Additional weight?

Negligible as compared with something like dynamat. An entire gallon weighs about 10 lbs and I only used about 1/3 of the gallon. I think I have enough left to do Crashy and my Tacoma.

[fnkngrv]

Originally Posted by CTScott

Negligible as compared with something like dynamat. An entire gallon weighs about 10 lbs and I only used about 1/3 of the gallon. I think I have enough left to do Crashy and my Tacoma.

wow...very nice! you should coat all over crashy...haha...that would be interesting

[UberSilver]

Originally Posted by fnkngrv

wow...very nice! you should coat all over crashy...haha...that would be interesting

Took 3 gallons for 2 thick coats on my LC

[CTScott]

I just realized that it has been a year since I undercoated it. Since Crashy and my 09 are in opposite spots in the garage in preparation for the impending blizzard, I put the 09 on the lift to see how the Herculiner is surviving. Not a bit has flaked off, even with the wicked road salt around here.

Hercu - Under.jpg

Hercu - Rear Fender.jpg

Hercu - Rear.jpg

[Deathegg]

Originally Posted by fnkngrv

Additional weight?

Even if it weighed 50 lbs, it would have a negligible effect on...well, anything! I plan to do something like this soon, the road noise is bad on these cars. Thank God the engine is fairly quiet at speed.

Good job! I never thought of bed coating... It dries very hard then?

[fnkngrv]

Originally Posted by Deathegg

Even if it weighed 50 lbs, it would have a negligible effect on...well, anything! I plan to do something like this soon, the road noise is bad on these cars. Thank God the engine is fairly quiet at speed.

Good job! I never thought of bed coating... It dries very hard then?

Not to burst your bubble, but you are incorrect. I can attest to that easily. 50lbs is 50lbs and will affect acceleration and braking. I see a very noticeable difference rolling on 15s as opposed to my 18s as well as whether or not I have my subwoofer box in the trunk or do not. Performing a spare tire delete even makes a difference. Every change you make to a car that is designed like the Yaris has an impact and you need to weigh the pros/cons. An example is going boosted and not only that, but whether or not you go SC or turbo when you gauge your FE. You very well trade FE for power.

[Deathegg]

Originally Posted by fnkngrv

Not to burst your bubble, but you are incorrect. I can attest to that easily. 50lbs is 50lbs and will affect acceleration and braking. I see a very noticeable difference rolling on 15s as opposed to my 18s as well as whether or not I have my subwoofer box in the trunk or do not. Performing a spare tire delete even makes a difference. Every change you make to a car that is designed like the Yaris has an impact and you need to weigh the pros/cons. An example is going boosted and not only that, but whether or not you go SC or turbo when you gauge your FE. You very well trade FE for power.

Wow, you must have a very sensitive backside if you notice the performance difference in 50 lbs. That's about 8 gallons of gas in the tank. If I take out the spare tire, my butt will not notice the difference. I would have to have a ScanGauge or similar instrumentation to tell the difference in MPG, acceleration, etc. Now, if you're talking about wheels and tires, that's a big difference in unsprung weight between 15" and 18". You'll notice that more than other weight reduction/increase.

[Viperoni]

Originally Posted by Deathegg

Wow, you must have a very sensitive backside if you notice the performance difference in 50 lbs. That's about 8 gallons of gas in the tank. If I take out the spare tire, my butt will not notice the difference. I would have to have a ScanGauge or similar instrumentation to tell the difference in MPG, acceleration, etc. Now, if you're talking about wheels and tires, that's a big difference in unsprung weight between 15" and 18". You'll notice that more than other weight reduction/increase.

Completely correct, you're noticing the unsprung weight difference, which coutns 4-10 times more than regular weight.

I can just barely feel the difference when I pull my sub box + amp out... and it's pushing 90lbs.


CTScott, do you have any vids of your mufflerless exhaust? Just wondering how it sounds.

[SAV912]

Originally Posted by fnkngrv

Not to burst your bubble, but you are incorrect. I can attest to that easily. 50lbs is 50lbs and will affect acceleration and braking. I see a very noticeable difference rolling on 15s as opposed to my 18s as well as whether or not I have my subwoofer box in the trunk or do not. Performing a spare tire delete even makes a difference. Every change you make to a car that is designed like the Yaris has an impact and you need to weigh the pros/cons. An example is going boosted and not only that, but whether or not you go SC or turbo when you gauge your FE. You very well trade FE for power.

Unsprung weight =/= dead weight. There will be a noticable difference on weight attached to parts of the car that directly handle the power vs weight somewhere else in the vehicle. That's why lighter wheels and tires are more noticable than removing the spare tire or a subwoofer.

But if you notice 50 lbs (which must be a hell of a hard hitting woofer), then more power to you. My butt dyno isn't that sensitive.

Scott, I'm thoroughly envious of your lift. And I may do the rubber brush on coating now. I've already done spray on bedliner and it made an appreciable difference, but I only did two coats on the wheel wells. I didn't do anything under the center of the car.

-C

[nookandcrannycar]

Originally Posted by fnkngrv

Performing a spare tire delete even makes a difference. .

Good to know. For everyday driving (unless going away on a trip), I'm going to remove mine. I have tire sealant and am paying extra for AAA plus coverage (longer free towing range). I've never needed either within my metro, but they'd be available if need be. Normally painless and transparent ways to increase MPG = all good in my book. I just thought (not based on more than a vague hunch really) removing it wouldn't make any difference. I trust your judgement. I don't think you would write this unless you had noticed a difference (even if it isn't much). Come to think of it, I can't remember the last time I had to put the spare to use in a car.

[nookandcrannycar]

^^^^^ Oops . I just read your other posts (and other's posts) on this thread and realize the difference you are referring to = in performance not MPG. Amazingly faulty assumption on my part, especially since you are 'Mr. 143'. Re my Yaris, I am probably too clouded by MPG as a first thought.

[nookandcrannycar]

^^^^^^^^^^^^^^^^^ Above (post #37 meant to appear below #36 but system posted to top of new page instead)

Originally Posted by nookandcrannycar

Good to know. For everyday driving (unless going away on a trip), I'm going to remove mine. I have tire sealant and am paying extra for AAA plus coverage (longer free towing range). I've never needed either within my metro, but they'd be available if need be. Normally painless and transparent ways to increase MPG = all good in my book. I just thought (not based on more than a vague hunch really) removing it wouldn't make any difference. I trust your judgement. I don't think you would write this unless you had noticed a difference (even if it isn't much). Come to think of it, I can't remember the last time I had to put the spare to use in a car.

[PHXDEMON]

Originally Posted by Deathegg

Even if it weighed 50 lbs, it would have a negligible effect on...well, anything! I plan to do something like this soon, the road noise is bad on these cars. Thank God the engine is fairly quiet at speed.

Good job! I never thought of bed coating... It dries very hard then?

50 lbs is noticeable in the yaris.

[enviri]

nice! I went with the more traditional fatmat at 1$/sq foot lol. I used only 50ft out of the 100 i bought, but plan on using a weee bit more when it warms up for the extremely noisy engine.

[mazilla]

Man, that lift is awesome...I'm drooling all over my desk!