For two reasons:

Remove weight. This is actually a bonus

Roll cage clearance. This is really what I want out of this.

Has anyone removed the "guts" of a hardtop? I think the inside layer may be bonded to the outside, but it is hard to tell whats all going on in there, without making some dust with a cutoff wheel. I have removed all the bolts, screws, rubber, rails and what trim comes off easy. I thought by this point it would become clear how these tops are built, but I did not.

I have not pulled out the glass yet, are they glued, or is it just a gasket?

If anyone has done this, what did you do to secure the top after gutting?

This is a race only car, I want it to look good still, but am not afraid to put round headed bolts through the top for mounting. It would be nice to mostly seal out water when finished.

I hope someone has been there, and can show some pics of what the outcome was. Even if partial stripping, cutting, or repairs even were done.

Ron

 

Are you willing to remove the glass? That's where the majority of the weight is. I have experience with two, a windowless snug-top, and a lexan windowed stock one. They're both so light I'm not sure I would consider taking out the inner layer. You'll loose all the mounting spots for the weather stripping you say you want to retain. Right?

 

I'd say you'd want to dremel out the inner layer, leaving the edges where all the weather sealing trim and such is... but all you're taking out is (I assume) a sheet of fiberglass that's 1/16" thick, so I'm not sure how much weight will come out at that point.

I would probably remove the glass and then weigh the top. Take that number and then figure by gutting the inner layer you can probably cut down 20-30% of that weight... then decide if that sounds worth it.

If you want to clear a roll bar, you can just cut out sections instead of the whole inside layer..

 

I don't think you'll shed as much weight as you think you will.

 

Treasure coast miata has a lightweight top they are working on. You might want to check it out before hacking one up.

New Light Weight Miata Hard Top

 

I just bought one from Treasure Coast Miata. It is very light, but the fit is terrible. I am going to have to do some serious work to it so it will fit right and look right. I am very happy with the weight for the price, so I am willing to go through the suffering.

 

Weight loss is not my primary goal here, it's a bonus. The inside has to be cut some for the cage to get up as high as possible, to get seat comfort, location, and to pass the "broomstick" rule (I want to be safe in the car)

I will be leaving the weatherstrip mounts and hopefully be able to use the stock locations for mounting, minus the Frankenstein setup. (that crap is certainly some excess weight)

I have a plan for the seal to the back deck, and the stock stuff is probably OK for removable windows and top of the windshield.

Lexan rear window is on the list as well.

miata2fast, I would really like to see some quality pics of the Treasure Coast hardtop, with some good closeups of how they did the mounting points and and weatherstrip areas. It looks a lot like what I would like to end up with. Shipping to Canada would be quite high, or I would think about selling my top and buying one of those, but then the accessories (seals and such) would put cost over the top (no pun intended)

 

I will get you the pics in the next day or two.

 

That would be great!

 

My HT weighs like 48lb. I'd pay $500 to drop 30lb.

 

Do you have pics of what doesn't fit right and what you are doing to make it fit. I will be living in FL once again, so it is going to be somewhat water tight.

It looks good for the price and will be perfect for the people that don't want to take it off again.

 

I intend to take pics of the problem areas. Most of the discussion on fixing it will be in my build thread, but I am aways from tackling that problem.

 

I've seen the one Troy bought and the part that fits to the windshield bow is not arched to match the curve of the windshield bow well. It also looks to be cut slightly off in the front to rear curvature where it meets the windshield bow. It is close but will need some sanding and shaping for proper alignment. Also, there is no second layer aft of the side latch mounting points to seal against the moulding around the entire back side. Under the little bumps in the fiberglass that would normally house the bases of the frankenstein mounts on the top there is nothing but daylight. This is designed to be track-only and is very lightweight on purpose.

 

A race-track only lightweight top is intended just as a skin for air to pass over, not something to seal against weather. There are tops available on the West Coast just like that Treasure Coast one, "fit" is terrible for a street car, but it serves the purpose it's intended to - being light.

If you are going to drive around on the street, possibly in rain, or park places where you want the car secure, it's really not for you.

Too often people want racecar parts but don't understand/aren't willing to accept the compromises that racecar stuff has - they think it's just a better/lighter/faster version of the OEM stuff. Very rarely so.

 

Amen!

Apparently Treasure Coast is attempting to make a street version of this top. I find it hard to believe that they will pull it off. At least with some semblance of quality.

I went into getting one knowing full well the realities.

 

I just contacted Treasure Coast about one of those and decided to go with an OEM. Not enough sealing for the Pacific NorthWet, when I can put on an OEM top with a sealed lexan window and have the majority of the weight savings and not get soaked (as badly) on track.

 

In for pics of lightweight hardtop. Treasure had my hopes up damnit.

 

FTFY

So something else for consideration... Way back when I was one of the fortunate ones that purchased a carbon hard top from Chaser Aero during a group buy. It is in my sig picture. Unlike some of their other stuff (vented hood group buy) these actually were quite nice and the price was great, cheaper than a used stock hard top. With a lexan window these are very light and the fit is like stock. I'll never sell mine unless I quit Miatas completely.

Problem is, Chaser has cranked up the price. However, assuming the stock top you have now is in good shape, you can sell it, and use the proceeds towards most of the cost of a Chaser top. Who knows, if you call them they may be willing to deal on the price.

Chaser links, not affiliated
Hard Tops : Chaser Aerodynamics, LLC.
I think mine is this one
Carbon Fiber Hard Top [CR825(CF)] - $1,499.00 : Chaser Aerodynamics, LLC.

Some say his hard tops are lead impregnated. And that he does it to keep spy satellites from mapping his brain activity while racing. All we know is, he's called The Hustler.

 

For the record, I explained the lack of sealing in the rear for the benefit of others who might be considering buying one for the street, not because I thought it a deficiency. Lightweight is definitely good for race cars.

 

I had a crappy copy hardtop from Chaser Aero. The finish was crap. I spent forever with bondo and sand paper to get a smooth surface for paint. It was really light though. I did cut through the interior panel of the top for clearance on the HardDog Hard Core roll bar.

Luckily, it was bought during the initial group buy for cheap. I can't see paying pretty much double now unless quality has gone WAY up.

With all the seals, Spec Miata brackets and lexan rear window; I think it weighed 28lbs. Weighted it at a Divsional Autox a few years back