Ok. Now that I sold my engine and have until July to wait for Special Edition to start my Subaru conversion. I am looking for some constructive work to do on my Speedster. I was thinking of doing something like covering the back of the back seat area with Dynomat or some other sound deadening material. I am looking for advise and suggestions on what others have done. Thanks in advance.
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But since you are replacing that ancient noisy hot air engine with a quiet water cooled engine you won't need the sound deadening??? Have you done the floors yet - that cuts down on road roar.
I plan to do the floors as well. I forgot to considered that the Subaru Engine will be quieter. Thanks for the reply.
Put the Dynamat in, you won't regret it. Also, put some inside the door skin and any flat fiberglass panel. You don't have to do every square inch, like 2/3 will suffice. You'll be amazed at the difference.
Ask Carey about the back of the back seat panel. He uses that area sometimes with Soob conversions to good effect for other purposes.
Thanks, I am planning on touching base with Carey before doing this.
Dynamat is a great addition no matter which engine you have. I did all of my VS interior with Dynamat after stripping the carpets out, slathering truck bed liner then Dynamat then a new carpet set from Kirk. Careful with the Dynamat backing---it will slice up your fingers---it['s like a thick aluminum foil and is pretty sharp. Not real deep cuts but still no fun. I'd use some yard gloves if I did it again. My doors shut with a very pleasing "thunk" and the road noise is cut down dramatically. If I were ordering a new car I'd spec the truck bed liner plus Dynamat along with along list of "must haves" that we all add later.
FYI, Gordon recommends another product which is a lot less monethan Dynamat and he says it also works well. I spending money on my Speedster is a pleasure though. Part of the madness, I'm sure.
I would do as much as I could I forgot to have the doors done which is my plans going forward
https://www.amazon.com/gp/aw/d...h&th=1&psc=1
Classic bug restorer uses this
Ray, the links don't quite match up to the "size" you click on. It has the right description, but the little "click" box says 3" x 25'. Amazon's faux-pas, not yours.
Still, 18" by 33 feet is quite a bit of sound deadening for a 16 pound penalty, so not as heavy as one would think. $108 US dollars for that size.
Thanks this looks good.
If you are considering Dynamat, read this about bituthene. Hard to believe I wrote it 13 years ago.
https://www.speedsterowners.co...895#2135445018603895
-=theron
I don’t know about you guys but with the top down the wind noise covers a lot of noise especially at speed.
When and If you do have the top up all the drivetrain noise gets amplified and even more so in a coupe so having full sound proofimg could certainly attenuate the tranny whine if your car in your rebuid was done on a bad day 
It is after all 50 year old technology
Yeah, I used something like Theron's stuff in my CMC at the rear of the back seat - Comes in a 3' wide roll at Lowes, but I also used 3/8" thick shop floor mat for under the carpet and as a liner inside of the doors. Glued it down with 3M Super 90 upholstery adhesive, but DAP Contact cement would work well and you can brush it on. All of that made a noticeable difference in road noise, especially with the top up, but didn't do much for the exhaust and intake note.
It's amazing how much intake noise there is, and is often mistaken for exhaust. I bought the CB performance aluminum turbo hats and a couple 2" K & N type cone filters. Also had to get shorter velocity stacks to leave enough clearance to the top of the hat. Don't forget the nice rubber base gasket too. Uses your existing air filter bases.
A really nice bonus is almost never plugging an idle jet!
Dropped the full-throttle noise at least 10 dB. Made quite a difference.
CB has another turbo hat that points down towards the rear of the car and those worked perfect also. It really does help the noise level.
It pretty much looks like this. Don't have a picture of mine right now but this is from intermeccanica website. Latest Rage is right by me so I picked up the short velocity stacks from them.
And that little filter allows enough air into the carbs?
Henry does it so that's good enough research for me.
IM buys all the type I engines from Pat Down and whenever Pat adds new stuff they usually get it but then the owner can order a la carte. IM knows that Remote support with a custom car needs good suppliers and they try to take the variables out... does not always happen but they try.
Terry Nuckels posted:And that little filter allows enough air into the carbs?
It does look a little more restrictive but for regular street use should be ok.
Theron posted:If you are considering Dynamat, read this about bituthene. Hard to believe I wrote it 13 years ago.
https://www.speedsterowners.co...895#2135445018603895-=theron
Ballistic also makes sound damping material which I understand is cheaper than Dynamat.
I love my intake and exhaust note!
Table manners
Cliff Presley - Charlotte, NC posted:Theron posted:If you are considering Dynamat, read this about bituthene. Hard to believe I wrote it 13 years ago.
https://www.speedsterowners.co...895#2135445018603895-=theron
Ballistic also makes sound damping material which I understand is cheaper than Dynamat.
That is the material that Henry used on my doors when it was up for the Turbo engine and 911 front end upgrades. Copy an paste this link. https://www.flickr.com/photos/65579473@N08/20217004358/in/album-72157650603303647
Terry Nuckels posted:And that little filter allows enough air into the carbs?
Yes, it does. Only one cylinder is drawing air at a time. The surface area of the filter is way greater than the intake throat size. Also, the 2" opening to the "hat" is larger than your 44-45mm throat and 36mm or so venturi. There is absolutely no performance loss that I have detected. Only noise loss.
Hey Carlos, finally got a pic in there of the breather I made.
I wonder if setting up the ends of the turbo hats to draw cool air from outside the engine bay would be of any benefit.
Also, Terry Nuckels, I think this was on FB but I'll respond here.
There isn't a way for me to use the Sync-Link. My carbs are reversed from most(idle jets to the inside) because of CB space-saver manifolds. These are port-matched to my heads so I'm not keen to change them. The Sync-link cables would not be facing each other on my application like they are on just about everyone elses. I guess it could be done with longer cables but since what I have works so well I'm not doing it.
Bummer. But, you're happy with your hexbar linkage, right?
Thanks for the photos. It looks like the downturned turbo hats would be a better fit in a speedster. @DannyP, do you have a direct link to the filter?
IMHO: the CB Hex bar Linkage, properly upgraded with Heim bearings on the ends, rather than the quickly wearing ball-in-socket that it comes with and adjusted properly to your carbs (and Commander Pip is a whiz at this) can provide you with a pretty damn good linkage system. As good as a "Sync-Link"? Maybe a tad less but I personally feel that most people would never notice any difference if they were both set up properly. Stan might, but he has a sensitive tush to that sort of thing.
@Terry Nuckels Here you go, it's in the turbo accessories: http://www.cbperformance.com/product-p/7303.htm
Gordon, I'll take the Pepsi challenge on that CB/Heim DannyP linkage vs SyncLink. Anytime.
Marty Grzynkowicz posted:Cliff Presley - Charlotte, NC posted:Theron posted:If you are considering Dynamat, read this about bituthene. Hard to believe I wrote it 13 years ago.
https://www.speedsterowners.co...895#2135445018603895-=theron
Ballistic also makes sound damping material which I understand is cheaper than Dynamat.
That is the material that Henry used on my doors when it was up for the Turbo engine and 911 front end upgrades. Copy an paste this link. https://www.flickr.com/photos/65579473@N08/20217004358/in/album-72157650603303647
So are you satisfied with the sound of the doors now that your went Ballistic with the turbo
I wonder how much of that stuff was needed to do the two doors? Thinking about getting some of it @Marty Grzynkowicz
The filters are also sold by empi. I bought mine from cip1. When it comes to noise reduction I read you only need about 25% coverage of the stuff in the link. People also get the rolls from home improvement stores in the roofing section. It's main job is to get rid of the rattles. Look into mass loaded vinyl to go over that with 100% coverage if you want to get heavy duty into noise reduction.
I used a sheet that was 15x18 for each door (or 12x15)? Super quiet and they feel great when you shut them.
