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Catalytic converter protection: Auto Defender vs. Cat Shield?

Discussion in 'Gen 3 Prius Accessories and Modifications' started by NewHybridOwner, May 17, 2020.

  1. ASRDogman

    ASRDogman Senior Member

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    I repeat: But as the heat rises, it draws in the cooler air. So it really should make any difference.
     
  2. Peter Chicarielli

    Peter Chicarielli Junior Member

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    Two nights ago my Prius' Cat was stolen from my apartment's parking lot. What a shitty feeling when I realized it wasn't some engine issue and it was actually theft.

    My other vehicle is a Honda Accord. I've heard from the guy at Midas, and the insurance agent, that both a Prius and Honda are common targets.

    To be safe, I think I'll get a shield for each vehicle ( I live in Philly/urban area).

    I know the two main brands that sell these shields are both around $180, but I found two ebay sellers that seem reputable that are offering them at $110 each (if I buy two).

    My only concern is quality. I just read someone's question about thermal temps, and it got me thinking, "Are these cheaper versions, also cheaper is quality, or is this all made from the same type of aluminum?"

    Other than that, hardware would be the big difference. I would think one-way screws would be sufficient since all we can really do is create a deterrent and not be the lowest hanging fruit.

    Any advice? I'd love to save $100 since I'm buying two. The $500 deductible is hard enough to swallow.

    I know you get what you pay for, but that doesn't necessarily translate to these e-bay items being a bad decision.

    Thanks everyone!
     
  3. Miller CAT

    Miller CAT Junior Member

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    Sorry for your loss. Not trying to be a salesman here but since you live in Philly salt roads and galvanic corrosion might be something you want to think about. All these shields you see online are probably made from Aluminum and they all probably require drilling into the frame of the car. When the Aluminum shields touch the exposed steel frame of the car you will get galvanic corrosion and that will intensify with the salt from the roads. We thought of this when we designed our shields and that is why we use Zinc coated rivet nuts. The Zinc from the rivet nut will insulate the steel from the aluminum. This will happen to anyone who lives near salt water and especially those that live where they salt the roads.
     
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  4. Georgina Rudkus

    Georgina Rudkus Senior Member

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    I was not confident of the supplied aluminum rivets and screws. Having extensively used blind rivets for many years, I have easily drilled out many aluminum rivets.

    On that account, I replaced all of the aluminum rivets with stainless steel ones backed with stainless steel fender washers. My experience is that stainless steel rivets are really difficult to drill out. The bit will not readily into them and just spins the rivet in the hole. This is because the friction between the rivet and the rivet hole is not enough to keep it from spinning. The edge of the thin rivet must be difficultly and tediously held with pliers to keep it from spinning while being drilled. Ideally it would be easier held at the other end if accessible, but not in the case of this install. The washers under the rivet head also increases the likelihood of the rivet spinning when drilled.

    Ultimately, the only for the shield to be removed way would be to grind off the rivet heads. That is obviously tedious and time consuming.
     
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  5. Mendel Leisk

    Mendel Leisk Senior Member

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    They could just cut a longitudinal split on the shield itself, pry it back. Probably just as time consuming and arduous.
     
  6. ASRDogman

    ASRDogman Senior Member

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    How often would you be removing it???
    Would you need to remove it?
    Other than having to replace the exhaust system. Again, how often? :)

     
  7. ice9

    ice9 Active Member

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    Using a plastic grommet and nylon flat washer fixes that problem even better.
     
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  8. Georgina Rudkus

    Georgina Rudkus Senior Member

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    Unfortunately, patent laws will not protect you from competitors. Personally, I held two utility patents for single and multi gang digital torque wrenches.

    To me, the time and attorney fees spent was a total waste.

    There are two kinds of patents; a utility patent and a design patent.

    A utility patent would mean that any covering of the catalytic converter area would be protected in the patent. It is unlikely that the US Patent Office would issue a patent for an under cover for the under part of a car, since under chassis coverings are not new and have been used since the first automobiles were made.

    You are more likely to be issued a design patent, for the specific look of your product. All your competition has to do is to make one minor change in the shape of the product or change the amount of coverage to avoid infringement. Consequently, a design patent would be required for each specific model of vehicle.

    Even if you were able to secure the most broad patent on your invention, it is up to you to spend the funds and legal fees required to defend your patent. Unless you are a large corporation with "deep pockets," you will not likely want to defend your patent.

    While any patent is mending, any competitor can legally make and sell as many exact copies of your product legally. Unless you registered your trademark legally, they can even use your logo without legal ramifications.

    In my experience, the only protection that is worth protecting is a "trade secret." Protection lasts forever like the formula for Coca Cola.

    The only way to beat the competition is to have low acquisition cost of raw materials, the low cost of labor and special secret techniques that reduce manufacturing cost to under price the competition. The other factor is reputation and desirability on the part of your customer.

    Continuous improvement over the competition is another edge over the competition.

    Selling a better pr

    That's the reason why overseas competitors like China beats Made in USA, even with tariffs, which are not paid by the overseas manufacturer or marketer, but by the end user.

    I wish you well, but these are the facts, unfortunately.
     
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  9. Miller CAT

    Miller CAT Junior Member

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    Cat Shield is proud and humbled that Toyota has chosen our products to be added to Toyota Associated Parts. Cat Shields
    . Incase anyone is wondering which catalytic converter antitheft device Toyota recommends for their dealers.
     
  10. dram91801

    dram91801 Junior Member

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    Where in Bellflower? did you do it yourself?
     
  11. Georgina Rudkus

    Georgina Rudkus Senior Member

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    Bellflower is a suburb of Los Angeles.
     
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  12. Robert Reichenbach

    Robert Reichenbach New Member

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    FWIW, I’ve had my Cat Security shield installed for a couple of months now and use an OBD2 Bluetooth dongle synched to the Dash Command app on my phone to monitor vehicle temps including the oxygen sensor. I have not noticed any increase in temps with the shield installed. The cat temp gets up to a little more than 1,000° F. with the engine under load but quickly drops to between 600° and 800° F. if the engine is off for any appreciable amount of time.
     
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  13. Tekken

    Tekken Member

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    You meant $40 for labor right? I like to know this place too if everything installed for $40
     
  14. scoobydrew

    scoobydrew Junior Member

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    To those who have installed one of the available shields on your Gen 3, have any of you noticed rattling under acceleration?

    I bought the CatSecurity shield and had it professionally installed last week by a shop. I can hear and even feel a rattle under mild acceleration on city streets. It also happens on the highway and is way worse (potentially due to wind buffeting).

    Just wanted to get some input before I take it back to the shop to have it inspected.
     
  15. Georgina Rudkus

    Georgina Rudkus Senior Member

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    Nope! No rattle or any noise at all.

    As I recall, there was very little clearance between the center of the plate and the catalytic converter. Pushing on it with the palm of my hand caused the plate to hit the converter.

    It was easily solved. I just pulled down the center of the plate to get a "reverse upside down crown" to clear the converter by at least half an inch.

    This cures what the sheet metal fabricators call "oil canning" or vibration in sheet metal. "Crowning" or putting two shallow folds to form an "X" cures this problem.
     
    #55 Georgina Rudkus, Nov 2, 2020
    Last edited: Nov 2, 2020
  16. knix6

    knix6 2013 4, 7/19 2011 prius 2

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    It seems like there should be a way you could wire a booby trap, for example when doors locked anyone/thing touches the underside of the car, they get a shock.
     
  17. 04priusnow

    04priusnow Active Member

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    All the defense anyone could ever need
     
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  18. wasambi

    wasambi New Member

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    I have the Millercat Gen2 Catshield installed on my Prius and I've had no issues with theft for quite some time now. The louver design on the Millercat Catshield is supposedly much better at ensuring the catalytic converter doesnt heat up. Millercat claims they tested all their designs to ensure there's no noticeable temperature spikes and this was the best design at cooling down certain areas. Another reason I went with Millercat Catshield is because I've heard defender installs being an issue when it comes to Prius maintenance or repairs since they use a one-way screw.. Millercat Catshield on the otherhand, no issues there. They recently partnered with Toyota for their Catshields. You know Toyota wont partner unless you have something good! Here's an update from their website:

    We are proud to announce that our Cat Shields are now a part of Toyota’s exclusive Toyota Associated Products catalog. We are honored that Toyota is making our Cat Shield available to every Toyota dealership and have been given this distinguished recognition. This is just a testament to the quality of our products, manufacturing capabilities, and smart engineering. We are only encouraged to keep continuing to improve our products and offer our customers the best protection device on the market.
     
    #58 wasambi, Nov 24, 2020
    Last edited: Nov 24, 2020
  19. wasambi

    wasambi New Member

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    Not sure if the rear plate is even necessary either.. I'd say it's more of an asthetics approach...? Becuase all a theif needs to steal the catalytic converter is access to the front. thoughts?
     
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  20. tvirtue

    tvirtue Junior Member

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    your posts are so informative and GREATLY appreciated! ...then when you said you live in california i felt a major sense of peace! just knowing good helpful and highly knowledgeable people like you exist out here literally made me exhale. i am looking at millercat and also live in los angeles where these thefts are so common and the criminals so bold... they actually RETURN to steal the new catalytic converters. the LAPD had an undercover team working in our neighborhood and caught the scumbags red handed at 12 noon during the week!

    thank you for all of your advice, suggestions and intelligent responses to people’s questions!
     
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