JeffsGoblin
Goblin Guru
Nuker ran it in front of the DF HE before he replaced it. Alex is running it behind the DF HE.
AleX1/9's City Goblin - 07 SS/SC donor - Chassis #18 - WA registered
- Thread starter AleX1/9
- Start date
Waterdriver
Goblin Guru
Do you think your ready to do some testing?
Bremerton Sports Car Club is having a test-n-tune 5/27/18 and event 4 autocross the next day.
Bremerton Sports Car Club is having a test-n-tune 5/27/18 and event 4 autocross the next day.
AleX1/9
Well-Known Member
Super Ready! Unfortunately I will be working all Memorial Day weekend.
Took it for a short drive down the county road behind my house. This thing is fast!
Waterdriver
Goblin Guru
There's a track day event at The Ridge in Shelton, June 9th. If your interested I could see if the Corvette club would allow other marques on track with them. Vipers would be there too. Heavy sports cars to play with a tease.
I'm trying to get mine finished in time but I don't think I'll be quite ready.
CncMan333
Active Member
Was the main purpose of the Dynamat for road noise or heat from the engine compartment?
CncMan333
Active Member
Do you have any pictures of that?
CncMan333
Active Member
The closest thing I have been able to find online to see how you would do anything less than 100% coverage (which seems to be the recommendation for stereo applications) is an example for deadening the sound from a washer or dryer where they had a square patch in the middle of the side. Is that the kind of treatment you would do to benefit the Goblin sheet metal?
RichRich
Well-Known Member
Not sure why I said 10%, that was a typo it's like 30% coverage but of course it does better the more surface area that is covered. I did 95-100% whenever I've used it. The thing that already helps the goblin is having the silicon in between the tube and sheet metal.
Found this quote online by crutchfield "The minimum coverage recommended by Dynamat for basic resonance control is 30% of the area of any panel when using Dynamat Extreme. Do that, and you’ll hear a difference."
Again, this is for car audio and road noise from a full vehicle. I doubt you will get much benefit in a goblin
I haven't used it on my goblin but I still have a bunch of it laying in my tool box so I may make use of it. Not sure I would go out and spend the money on it, in fact even having used it MANY times in years past I wouldn't do it unless you have it laying around
Found this quote online by crutchfield "The minimum coverage recommended by Dynamat for basic resonance control is 30% of the area of any panel when using Dynamat Extreme. Do that, and you’ll hear a difference."
Again, this is for car audio and road noise from a full vehicle. I doubt you will get much benefit in a goblin
I haven't used it on my goblin but I still have a bunch of it laying in my tool box so I may make use of it. Not sure I would go out and spend the money on it, in fact even having used it MANY times in years past I wouldn't do it unless you have it laying around
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Briann1177
Goblin Guru
Just use silicone where the sheet metal contacts the frame, and you should be good to go as far as rattles.
AleX1/9
Well-Known Member
Started making a fiberglass hood this week. The plan is to make a small hood that hinges up for access, and doesn’t cover the frame tubes (except for the cowl/hinge piece). Also needs to be sturdy enough to mount a lexan windshield to at some point. Not going to include a nose cone. Gonna use hood pins to attach at the front.
Started by welding up a steel frame with attached hinge points. Then shaped a huge piece of 1/4” foam board into a 1 piece form and glued it to the frame.
Next step will be applying a release layer. I’ve used aluminum foil before, but might try something different.
I also need to find some suitable fleece for the stretch layer.
Started by welding up a steel frame with attached hinge points. Then shaped a huge piece of 1/4” foam board into a 1 piece form and glued it to the frame.
Next step will be applying a release layer. I’ve used aluminum foil before, but might try something different.
I also need to find some suitable fleece for the stretch layer.
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JSATX
Goblin Guru
That looks great! What type of foam board did you use?
I used standard polyester fleece, cheap and readily available.
But I’m not sure why you would want to use fleece on the foam? The point of using fleece (for me) was because I tried and tried to get a suitable backer layer of foam and just couldn’t do it. The fleece provided the form, but foam would do the job much better.
Oh also the fleece has to be stretched TIGHT. I could see a situation where you collapse or otherwise deform your foam shape trying to stretch the fleece over it.
I used standard polyester fleece, cheap and readily available.
But I’m not sure why you would want to use fleece on the foam? The point of using fleece (for me) was because I tried and tried to get a suitable backer layer of foam and just couldn’t do it. The fleece provided the form, but foam would do the job much better.
Oh also the fleece has to be stretched TIGHT. I could see a situation where you collapse or otherwise deform your foam shape trying to stretch the fleece over it.
JSATX
Goblin Guru
Also while you’re at it, consider working on an air dam behind the radiator. I’m venting mine out the top of the hood. There’s quite a lot of warm air that flows over your legs while driving. That might be nice up in your neck of the woods but down here it feels like you’re getting slow cooked.
AleX1/9
Well-Known Member
Thanks for the heads up on this! I think venting out the hood is best, considering the front end is light enough as it is without air pushing up on the front.
The foam board is the type you would use for backing a large painting, or a presentation board type deal. Got it at a picture framing shop. Very rigid yet pliable and holds a shape when formed. I’m using this below the fleece because in past experiences, the wetted fleece tends to sag and give undesired shapes, especially with such large expanses. The plan is to glue the fleece on the front edge, and stretch up towards the cowl, gluing as I go to get it real tight. Really to goal is to fill the 1/16” gap/void on top of the foam board and up to the level of the steel frame so I can get a perfectly flat first layer. That way the tension isn’t super crucial.
If I can get it real flat and uniform, I might be able to use a fancy top layer like Kevlar or carbon fiber
If it turns out lumpy and uneven, I’ll just bodywork and paint, at the very least I want to minimize that step... I hate filler work!
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Balphamore
Active Member
The hood idea is pretty slick. How's it going so far? May I ask, is the frame for your hood made of u channel, so you can slip the foam board into it? And keep some shape?
AleX1/9
Well-Known Member
I used flat bar, I like your idea on the channel though, especially if you can use / weld aluminum. Steel would be quite heavy.
I finally sourced some 50” roll fiberglass cloth locally, and currently have 3 top layers done. Ready to pull the foam out the back and do 2 layers on the underside before bodywork:
Used aluminum foil for release:
Contoured some with duct tape, then stretched and glued the thinnest fleece I could find
Wetted that out, attached to sawhorses to keep its shape while glassing. Some edges were popping, so epoxied and clamped down
First layer of glass, dry then wetted
Balphamore
Active Member
Nice work so far. I think I saw in your thread. About also figuring out how to mount a windscreen. When you run the fiberglass on the under side of the hood. Did you think about some aluminum or steel for the support of the windscreen? Via lamination between the layers of fiberglass.