I didn't think Dynamat was rigid enough to withstand road debris. It's great for a heat reflector but rocks? I still think a rubberized coating would be more efficient for the intended purpose.
John

ST, thanks for the #

Actually, you do need a rigid material, almost like a second skin. Dynamat also has the tar-like material between the aluminum sheet and the fender, absorbing any impact. FWIW A rubberized coating will NOT prevent star cracks. The fender that got the crack on my previous SB had rubberized undercoating almost 3/8" thick before the injury.

When I run my set of sticky GY slicks, I can hear the debris and pebbles being kicked up the fender, and TG, not a crack yet.

I would agree that a rubberized coating ALONE will not prevent star cracks. It will arguably eliminate many opportunities for them, but the occasional rogue rock (i.e. large) will give you pain. Adding another layer (neoprene, Dynamat, etc.) along with a couple coats of rubberized coating is about the most care you can apply to the inner fenders to hopefully prevent a problem. No system is a sure guarantee. For me $50 in materials and killing a Saturday was a lot easier than dealing with a potential a star crack. And (God forbid) if I still get one, well then shame on me for putting such a sticky tire on a fiberglass-bodied car.

-Dean #747

just bought the high density foam from Top of the hill. Its precut for the
my spf, got the adhessive backing, also included is 1 tube of urathane sealer. Now I need to ask my friend when can I put the car on his lift to put it on. By the way, top of the hill also does installation if you can take your car to them.

There is a product called Star Blocker on the market that will solve your problems. I have it in my aluminum fenderwells and I don't have ANY stars from underneath. Check it out at www.starblocker.com
Good luck to you!

cobra crazee, how much was that kit from Top of the Hill?? you can pm me if you like. how was the fit and what was it made of.

thanks, Mel

It might sound crazy but on the two Unique cars I built - I used those dense foam camping mats. I cut the shapes and used Liquid nails to stick them on inside the fenders.

Never had a problem. The foam is about 1/2" thick so it can absorb allot of punishment.

I just installed the foam fender liners from Top-of-the-Hill Performance yesterday on my #770 SPF Roadster. I jacked up the car and put it on jackstands...removed the wheels and had at it.

The foam is closed cell rubber stuff, about 5/16" thick and comes with a sticky back double sided adhesive already applied. The instructions have you wash the underside of the fenders with soap & water, then wipe them down with a wax and grease remover when they're dry. I used Ditz-O...from the local automotive paint store...good stuff. The foam pads are precut and fit pretty nicely. You still have to jocky them around a bit and work carefully and slowly on the compound curved (concaved) inner fenders. They're not hard to install, but tedious. I found just pulling a little of the paper backing off - about 4", or so - then locating the pad in the right place and sticking the exposed part down, then removing the rest of the backing paper worked well for me. I also used a small wooden wallpaper seam roller to insure the pads were stuck to the inner fender well. Dunno where I got it...but probably at Home Depot. Just roll it back and forth across the underside of the fender from side to side over the foam rubber...worked pertty well, stuck everything down nicely.

The kit also came with a tube of DuPont urethane adhesive to seal and stick the edges down with. The instructions say to wear gloves and form a seal along the edges of the rubber foam with it. I'm here to tell you, guys...this sh!t is some nasty stuff....! It gets everywhere fast - real fast! It was all over my nitrile gloves in a heartbeat...then all over the handle of the caulk gun, then all over anything it came near. I finally stopped and wet a blue paper shop towel with some lacquer thinner and wiped off my gloves and everything else that damned stuff came in contact with. Man...this stuff is nasty! But, it works well...even if the caulk gun is difficult to get into tight corners, etc. I wasn't able to get the urethane on all edges, so I concentrated on the areas and edges that would most probably get splashed with water. Since I don't drive my car in the rain, I'm not too worried about sealing all the edges...I guess time will tell.

All in all, the kit seemed to be worth the money, more or less. $220 for the four (4) pre-cut, fitted foam mats of 5/16" black foam rubber, plus $20 for the tube of urethane (which you may be able to get this cheaper locally, I dunno), and $20 for shipping, for a total of $260, delivered. They estimate 4 hours to install, and I'd pretty much second that...

Do they work? Hell...I guess I'll find out over the next few months. No stars, so far, and I've had #770 for over six years. So, I guess I've been lucky.

Hope this helps someone out...

I used a 3' x 6' 7/16 black foam rubber sleeping bag pad from Eastern Mountain Sports, I made a template for each wheel well from large oaktag paper. Since the pad had no adhesive backing I used 3M general adhesive spray on the back of the pad and in the wheel well....it cost $50 for 2 pads, 2 pieces of oaktag and 1 can of spray and several hours of my time. Basicly the same as Freddie just more work :D

Tony

Hey Freddie - Good job! You will be very pleased...

Craig installed this same product on my SPF 7 years ago. Back then I was open tracking my SPF with Goodyear slicks, which picked up everything when they got warmed up. I've got almost 14k miles on my SPF (I had some title issues that grounded me for a year or two), however not one star, ding, blemish from rocks due solely to Craig's product.

So, yes, they work - they work well. This why I recommended TOTH a month ago on this thread - for $260, this is a no-brainer for any SPF owner.

Regards,
Randy R...

I'm still waiting to test a sample I got a hold of recently. This GD New England weather just won't cut us a break. Maybe one of these days the temp will get above 50 and I can check the material for adhesion. I think it's a bit pricey, but if it sticks it will be worth the money to me.

Bob

My superformance should be arriving to Dynamic next week, figured it would be good to enquire about this issue.

I was pleasantly surprised to find out that the car comes from the factory with padding in the fender wells. They also explained that they use a patented way of mounting the body to the frame where it floats so a not to get stress cracks from frame movement.

Hey, Randy...nice to hear from you. And even nicer to hear the TOTH foam padding works so well. I'm running the same Goodyear "Billboard" tires, but with the laser-cut grooves in them. And, like you, I've experienced the tires picking up almost everything in the road. They seem to grip very well, but they sure do pick up rocks and everything else...! My only complaint is - since they are bias-ply tires - how they dart around and follow every ridge, rut, crack and crevice in the road when they're cold, and flat-spot overnight. Most of that goes away once they warm up, but you really have to be alert when you're driving off on cold tires. But, I sure like the way they look and how they grip. I'll need some new track tires this year, and I'm thinking about the same Goodyears, but the slicks instead of grooves. They seem to be a good choice for 15" wheels. Did you get yours at Roger Krause Racing?

Tony...sounds like you indeed have a cheaper version of the same thing, and your foam is a little thicker, too. Wish I had thought about your approach before I bought the kit from TOTH. Have you had any problems with the 3M adhesive coming loose once the weather gets warm...?

Freddie...The foam has been on a year and still holding, although I haven't driven through any torrential rain storms, I guess that would be the real test..

Tony

I just put 2 test pieces of neoprene (5/16) on my SPF. The material is that used by Top of the Hill. I put one piece on according to instructions. The second piece I applied 3M adhesive on the fender first and then applied the neoprene. I'll let you know on 6-15-07 how they look.

If it's still tight I will allow the guys at Top of the Hill to over-charge me for the kit.

Bob

Inner Fender Rock Protection
 

Hey guys,

Let me know If you came up with a solution for your inner fenders. I would be happy to make up a few different products for you guys to try if you are interested. All I would need is a shipping address and a couple of templates. We have plenty of materials on hand for you guys to test if you would want to. Feel free to contact me at Sales@thermalsound.com.

www.thermalsound.com

Both test pieces (see earlier post) that I put on 3 weeks ago are still on tight. Tomorrow I will contact Top of the Hill and get very overcharged for 4 pieces of adhesive backed neoprene. It's expensive, but it seems to work.

Bob

While they don't have to worry about stars upon thars, they still get nice outty dents.
I bought some padding from The of the Hill. The coverage was much better than the stock SPF and the padding was thinker. It was pricy but saved me lots of time with the self sticking backing and there was no need to trim the pieces. :)

Called Top of the Hill today to order my kit. It was a little more than Flyin_Freddie was charged. Neoprene $240, adhesive $20, shipping $12 and handling $18. for a grand total of $290.00! The $18 to put it in a box really annoyed me since I thought TOTH was already doing OK getting $260 for the kit.

At any rate, I've decided to follow Tony Aprile's advice and save over $200 big ones. Tony, do you think Dick's Sporting Goods will have the neoprene?

Bob