The ERA Slabside Q and A Thread

[dacobb]

Given the popularity of this version of the Cobra, I thought it might be worth it to consolidate all of the questions about building this car into just one thread, versus having this info spread throughout the various Slabside build threads out there (including my own).

Going forward, I plan to update my build in that thread, but ask questions in this one.

Hope you other Slabside guys think this is a good idea.

[dacobb]

So my first question is regarding insulation. I plan to place heat barrier insulation under the car and heat/sound barrier insulation in the cockpit.

What brand/product are you using or planning to use? There's a lot to choose from it seems.

[dacobb]

Also, if you are planning to purchase one of these gems, this might be a good place to ask us who have already pulled the trigger.

[desgros@vtlink.]

My ERA Slabside #3010 is my dream come true. Peter and his crew are simply outstand making ownership of the Slabside a real pleasure.









John
ERA Slabside #3010 289 BRG

[dacobb]

Originally Posted by desgros@vtlink.

My ERA Slabside #3010 is my dream come true. Peter and his crew are simply outstand making ownership of the Slabside a real pleasure.









John
ERA Slabside #3010 289 BRG

Yours is completed, correct?

[DanEC]

Originally Posted by dacobb

So my first question is regarding insulation. I plan to place heat barrier insulation under the car and heat/sound barrier insulation in the cockpit.

What brand/product are you using or planning to use? There's a lot to choose from it seems.

Not a slabside but an undercar exhaust car. I applied Lizardskin, a ceramic coating, on the underside of my floor panels, rear wheel well/trunk panesl and transmission tunnel. I have had some bubbling directly above my mufflers where it seems to have lost adhesion in areas. That could be due to my not scuffing up the aluminum enough for a good bite into it or just a limitation on the material. Otherwise, it probably helps but it's not enough and something is needed on top of the floor panels on the inside to. Not sure if I would use it again.

I applied a mastic dampening material (B-Quiet) and then a temperature material over that (Thermo-Tec) on the top side on the floor pans. I would not use the B-Quiet again probably due to it's weight. Instead I would use Frost King duct insulation like ERA applies to the foot boxes and I think it has a better insulation rating. It probably weights half as much. the Thermo Tec was a foil-surfaced, woven silica insulation and a self-adhesive backing. Very good stuff, not real expensive and light weight.

Lots of good products out there. Some are primarily for dampening road noise and vibration more than for insulation value.

[desgros@vtlink.]

Yes, my Slabside was built by ERA - Turnkey.


John
ERA #3010 BRG 289

[dacobb]

Unless someone talks me out of it, right now my choice is the Dynamat product. Somewhat expensive, but made in the USA which is a must for me.

The plan is to place Dynamat Extreme (sound), a 67 mil product inside the cockpit, then add the Dynaliner (thermal) either 1/8" or 1/4" on top of that, as recommended by the manufacturer.

Under the car, I will use either 1/4" or 1/2" Dynaliner.

I should end up with a pretty good sound/thermal barrier with that setup.

With the Dynaliner, should I go thin (1/8" top and 1/4" bottom), or thicker (1/4" top and 1/2" bottom)?

Or I could go 1/8" top and 1/2" bottom.

The Thermo Tec product also appears to be top notch and would be considered as well.

[DanEC]

Do any of the Dynomat or Dynaliner products actually quote a U-factor? If so I would take a look at those and compare to the Thermo Tec product.

Something I did also was run insulation across the top of the foot boxes inside the cockpit since they are exposed to the hot cockpit. I would be inclined to go the 1/4 stuff on all the floors or at least under the seats, possibly the end and top of the foot boxes, and use the 1/8 stuff everywhere else. The 1/2" stuff sounds really thick and will probably pose issues getting the seats bolted down and fitting the carpets. ERA cautions against using too thick of insulation to avoid problems fitting the carpets and getting them to lie flat and smooth. I didn't really have any trouble with all I put under the carpet but it probably is a caution to be aware of.

In general to the ERA community, has anyone used an insulation as thick as 1/2" on their floors?

[dacobb]

Originally Posted by DanEC

Do any of the Dynomat or Dynaliner products actually quote a U-factor? If so I would take a look at those and compare to the Thermo Tec product.

Something I did also was run insulation across the top of the foot boxes inside the cockpit since they are exposed to the hot cockpit. I would be inclined to go the 1/4 stuff on all the floors or at least under the seats, possibly the end and top of the foot boxes, and use the 1/8 stuff everywhere else. The 1/2" stuff sounds really thick and will probably pose issues getting the seats bolted down and fitting the carpets. ERA cautions against using too thick of insulation to avoid problems fitting the carpets and getting them to lie flat and smooth. I didn't really have any trouble with all I put under the carpet but it probably is a caution to be aware of.

In general to the ERA community, has anyone used an insulation as thick as 1/2" on their floors?

I could not find much tech data on their website. Like you I’d like to know more.

The Thermo Tec Super Sonic is 70 mil vs 67 mil of the Dynamat. That’s still pretty thin and might offer better sound deadening without it being too thick for carpets.

And then use 1/8” heat insulator on floor and 1/4” or 1/2” elsewhere.

The thin stuff should work pretty well on those exposed wheel wells that intrude behind the seats.

I too wonder if all that would be too thick for the seat bolts. I suppose you could cut around them.

So many choices

[dacobb]

So here's today's topic - Tires

My understanding is the ERA slabside will accept either 205/70r15 or 215/65r15 tires.

I am having difficulty finding a whitewall tire in either size.

Maxxis, a tire company from Taiwan, makes a 3/4" whitewall in the 205 size.

I can't find anyone who makes a whitewall in the 215 size.

And the coolest tire I have found is the Vredestein Sprint Classic which are about $250 each, but only in blackwall.

So, 1) are you considering a whitewall tire, and if yes 2) have you found one?

[LMH]

Originally Posted by dacobb

So here's today's topic - Tires

My understanding is the ERA slabside will accept either 205/70r15 or 215/65r15 tires.

I am having difficulty finding a whitewall tire in either size.

Maxxis, a tire company from Taiwan, makes a 3/4" whitewall in the 205 size.

I can't find anyone who makes a whitewall in the 215 size.

And the coolest tire I have found is the Vredestein Sprint Classic which are about $250 each, but only in blackwall.

So, 1) are you considering a whitewall tire, and if yes 2) have you found one?

It’s totally personal preference but we’ve found the Michelin XWX 215/70-15 to be about the best looking tire and best performer on the market! Its not a white wall but it’s profile and tread pattern look “right” and I think you’d find it’s what most original owners use on their cars.
Larry

[1985 CCX]

Street dash
ERA rear end package
Leather seats
Full street wire wheel.
No stripes......

[DanEC]

You might talk to Diamondback Tires. I don't see a tire exactly like you are describing but they custom stripe a lot of their tires on current, quality radial tire casings. They might be able to put together what you want. They have a good reputation.

[dacobb]

Originally Posted by DanEC

You might talk to Diamondback Tires. I don't see a tire exactly like you are describing but they custom stripe a lot of their tires on current, quality radial tire casings. They might be able to put together what you want. They have a good reputation.

Thanks I will check them out.

[dacobb]

Would red line tires look stupid on a Slabside?

I'm thinking...probably.

But maybe not.

[dacobb]

Originally Posted by LMH

It’s totally personal preference but we’ve found the Michelin XWX 215/70-15 to be about the best looking tire and best performer on the market! Its not a white wall but it’s profile and tread pattern look “right” and I think you’d find it’s what most original owners use on their cars.
Larry

I had those on my 1985 BMW 535.


Didn't know they are still making them.

[LMH]

Larry

[xb-60]

Another tyre that might be worth considering is the Pirelli Cinturato P5 in a 225/65R15 size.
Might just be a little too wide (appearance-wise) on a 289 Cobra. I do however have them on my Alfa in that size on 6" wide rims and they work well. They are an excellent tyre for grip - and quite anomalous - very long lasting too.

Cheers!
Glen

[desgros@vtlink.]

Larry,

Just like the tires on my Slabside.

John
ERA Slabside #3010 289 BRG