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1] don't buy the most expensive stuff for each job, shop around. eg: Raamat is basically the same thing as the more expensive butyl/aluminum that Second Skin and Dynamat sells, but for way less. And Martyn Taylor did the whole paint-on sound-deadening thing and found it to not be worth the time and money. 2] for closed-cell foam and Mass-Loaded-Vinyl, Second Skin's Luxury Liner Pro is where you NEED to spend your money. If I only did one thing, I would only do LLP. If you listen carefully you can hear what sounds like a whine of a supercharger in my video. The mic capturing audio was right on the tranny tunnel. That tranny, while it shifts fine, is whiney with standard insulation--it's just getting old. It was pretty apparent without the insulation. With the LLP, I forgot about trying to find another used, but more quiet transmission. It's THAT good. The amount of whine you hear is only that loud because the mic is sitting right on the tunnel. 3] the Great Stuff foam in the frame is difficult and not practical for most people, and you have to watch out for things like the gas door release, or the door-closed light switches not getting gummed up. I think I used over 20 cans of the stuff. Also as for squirt-foam, if you think you want to add "structural foam" to the car instead, bear in mind, I had numerous conversations with structural engineers (even at Handi Foam) who agreed with me, after I researched SAE papers on the subject, that TRUE structural foam in a steel unibody car must weigh 8 pounds per cubic ft to "start" with, and go up from there. HandiFoam, while being some stout stuff, only weighs 2 pcf. The great stuff is probably more like 1 pcf. There's a ratio of strength the foam has to have compared to the steel skin and if the ratio is too low, you end up with a foam burrito in your frame and no structural support. So, to squirt such heavy foam into the entire frame of your car would add a ton of weight. Better to do it only in the joints, which is difficult to isolate (drill holes and blow up balloons to act as dams in the members--something like that) see the papers I found on the web here: [ http://mwsmotorsports.com/z32/foam/Structural_Foam_Forum.html ] and you can look up all my arguments with former members using search. Bottom line, spending sereval hundred dollars on 8pcf foam, IF you can find it in an applicator that we can all use, is not worth the expenditure, just for sound-deadening, IMHO. But Great Stuff is cheap, and helps a bit with the sound issue. One thing I did notice about sound-deadening the Z, was this: noises that were there before, but I could not hear, suddenly became apparent, because they used to be covered up. Like the sound of the one-piece driveshaft, which was clocked fine and barely vibrated, now made a bit of sound at 80 mph I had not noticed. It will definitely make you aware of what "else" needs to be quieted down. I also became instantly aware that my plastic hub-centering rings sucked and I needed aluminum.
_MWS Disclaimer: Some people have confused myself, Michael Smith of MWS
Motorsports with Mike Smith of MS Performance / Jim Wolf Technologies,
featured in Mike Kojima's Sport Compact Car magazine Project Z articles.
While the comparison is flattering, it is important to make the distinction.
Please help spread the word by always try to refer to each "Mike Smith" by
their respective companies. |
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