1. Attachments are working again! Check out this thread for more details and to report any other bugs.

Catalytic converter protection: Auto Defender vs. Cat Shield?

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

  1. Miller CAT

    Miller CAT Junior Member

    Joined:
    Apr 21, 2020
    25
    49
    0
    Location:
    San Jose, CA
    Vehicle:
    2013 Prius
    Model:
    Three
    Actually... we have used Torx screws and several other Tamperproof screws. We recently just came out with our own custom made screws to give you the ultimate level of security.
     
    tvirtue likes this.
  2. Georgina Rudkus

    Georgina Rudkus Senior Member

    Joined:
    Sep 15, 2018
    3,118
    2,172
    0
    Location:
    Taylors, SC
    Vehicle:
    2012 Prius v wagon
    Model:
    Two
    cat defender shield mounted on Prius v 2.JPG driver side cat mounting.JPG cat defender front plate rear passenger side mounting 2.JPG I used M6 T27 security Torx screws and filled them with JB Weld. Thy would have to be removed with damaged screw head extractors.

    I also cut off the rivet shanks and epoxied the heads to the empty holes in the aluminum plate to stymie the would be thieves.
     
    tvirtue, m2b and ice9 like this.
  3. ice9

    ice9 Active Member

    Joined:
    May 3, 2019
    581
    343
    1
    Location:
    norfolk va
    Vehicle:
    2018 Prius
    Model:
    Four
    I assume you are not having any issues with heat dissipation with this installation... ...How long have you had this kit installed?
     
  4. ETC(SS)

    ETC(SS) The OTHER One Percenter.....

    Joined:
    Oct 28, 2010
    7,673
    6,490
    0
    Location:
    Redneck Riviera (Gulf South)
    Vehicle:
    Other Non-Hybrid
    Model:
    N/A
    I'd hire a "Red Team" to see how long it takes to buzz through that plate with a sawz-all, and give them a $1,000 bounty if they can be "gone in 60 seconds."
    I work with electronics but I also used to throw very expensive toys in the ocean, and I have some passing familiarity with portable powered cutters, pinchers and benders - and portable power took technology has progressed a LOT while I've been fixing phones for a living!!

    I'd also consider adding some material (maybe not aluminum) to the two likely places that the would-be thieves would cut-cut-bend before they cut-cut-run.

    Remember.....by the time they see the plate, they've already jacked up the car and posted a sentry, and have the get-away car idling, nose out with the driver listening for alarms/police calls/etc.
    If I'm holding the saw, I'm already committed to either making the attempt, or I have to drop the car, grab the jack-stands, reel in my over-watch and go looking for another Prius to make a quick $250 on.
    You're either dealing with a team who has an order to fill OR you're dealing with one or two people trying to satisfy a drug habit, feed kids, etc.

    BOTH are highly motivated not to drive away with an empty pickup bed.

    You cannot afford to have very many people in Prius forums complain about jacked cats that were....."defended."


    ...your call.
     
    #24 ETC(SS), Jul 2, 2020
    Last edited: Jul 2, 2020
  5. Georgina Rudkus

    Georgina Rudkus Senior Member

    Joined:
    Sep 15, 2018
    3,118
    2,172
    0
    Location:
    Taylors, SC
    Vehicle:
    2012 Prius v wagon
    Model:
    Two
    No issues. Scan Gauge 2 shows normal operating temperature at 188-191 degrees F.

    I installed it about 10 days, ago.
     
    #25 Georgina Rudkus, Jul 2, 2020
    Last edited: Jul 2, 2020
    tvirtue, ice9 and Grit like this.
  6. Georgina Rudkus

    Georgina Rudkus Senior Member

    Joined:
    Sep 15, 2018
    3,118
    2,172
    0
    Location:
    Taylors, SC
    Vehicle:
    2012 Prius v wagon
    Model:
    Two
    Professionals thieves prefer Gen 2's. One cut and two bolts to remove.

    Gen 3's cats are tougher to remove;

    Because of the heat exchanger, four strategic cuts need to be made, and hot sticky smelly red coolant will spew out and pool below the car. There is NO way to avoid the coolant coming out. After that, the thief needs to lay in a pool of coolant with a long extension and ratchet to take off the bolts. The cats are closed together and in a very tight place that makes it hard to use a bulky battery powered Sawzall. Otherwise, the right front tire needs to be jacked up and removed. A 12 inch or longer Sawzall blade is then needed to reach the attachment pipe.

    Gen 4's are even tougher.
     
    #26 Georgina Rudkus, Jul 2, 2020
    Last edited: Jul 2, 2020
    tvirtue, m2b and 2012 Prius v wagon 3 like this.
  7. Mendel Leisk

    Mendel Leisk Senior Member

    Joined:
    Oct 17, 2010
    54,629
    38,195
    80
    Location:
    Greater Vancouver, British Columbia, Canada
    Vehicle:
    2010 Prius
    Model:
    Touring
    It may be stone-cold, just saying.

    Would low-deductable comprehensive insurance trump the need to armor the cat? One thing, if enough owners have such insurance, maybe something will get done, when the claims engulf the insurers, and they complain to law enforcement, local government.
     
    tvirtue and m2b like this.
  8. Georgina Rudkus

    Georgina Rudkus Senior Member

    Joined:
    Sep 15, 2018
    3,118
    2,172
    0
    Location:
    Taylors, SC
    Vehicle:
    2012 Prius v wagon
    Model:
    Two
    You will need rental car coverage, too. In California, only OEM converters are allowed on a Prius. If it is a Gen 3, no aftermarket heat exchangers are available. A thief would almost always cut through the heat exchanger.

    So, they many not be stocked by the dealer. Worse, if it needs to be ordered from Japan.
     
    #28 Georgina Rudkus, Jul 2, 2020
    Last edited: Jul 2, 2020
    tvirtue, m2b and Mendel Leisk like this.
  9. 2012 Prius v wagon 3

    2012 Prius v wagon 3 Active Member

    Joined:
    Sep 12, 2019
    281
    276
    0
    Location:
    Redwood City, California
    Vehicle:
    2012 Prius v wagon
    Model:
    Three
    Unfortunate, but true. We can only hope.

    Depends where you live. Where I live, law enforcement is controlled by the local government. And the local government sees this (and car break-ins, robberies, and looting) as a form of public assistance to the needy. Similar to farming, as long as you don't care about the victims, which they don't.
     
    Scienzchic, m2b, RMB and 2 others like this.
  10. Mendel Leisk

    Mendel Leisk Senior Member

    Joined:
    Oct 17, 2010
    54,629
    38,195
    80
    Location:
    Greater Vancouver, British Columbia, Canada
    Vehicle:
    2010 Prius
    Model:
    Touring
    Not sure I'm buying that, lol.
     
  11. Grit

    Grit Senior Member

    Joined:
    Aug 22, 2017
    6,109
    4,038
    1
    Location:
    Wilkes Land
    Vehicle:
    2012 Prius
    Model:
    Four
    What about Robin Hood then? Steal from rich and give to the poor. Buy that :ROFLMAO:

    Disclaimer- this reply may not apply in all situations.
     
    RMB and Mendel Leisk like this.
  12. ETC(SS)

    ETC(SS) The OTHER One Percenter.....

    Joined:
    Oct 28, 2010
    7,673
    6,490
    0
    Location:
    Redneck Riviera (Gulf South)
    Vehicle:
    Other Non-Hybrid
    Model:
    N/A
    Thieves are thieves, and while they certainly do not deserve to be physically harmed for being motivated by absurd state laws into collecting a roughly $250 bounty on a catalytic converter (YMMV) they ALSO should not be politely given a summons to appear and allowed to leave the scene......WITH their vehicles and tools.
    If you know what Prop-47 is then you KNOW that I'm not being my usual snarky self.

    I'm not sure what the solution to this 'little' problem is, BUT one that works in my part of the globe (where cat thievery involves ONLY felines) probably would not work where people DO have to engineer countermeasures for their cats.
    YMMV.

    Talent goes where the money is.

    G2's are getting on in years, and those that burn oil, foul out their catalytic converters.
    Owners are forced to chose between a $3,000 reppair bill or a $500 repair bill.
    Grey market shops pay around $250 for OEM cats - sans questions.....which BOTH satisfies one customer and creates another.

    This isn't hard to figure out.
    Ironically....the very victims of the cat shortage tell themselves that it cannot possibly be caused by the fact that in 48 other states, catalytic converters cost less NEW than the thieves are getting for stealing used ones from under other people's cars.
    G3s that are marginally cared for very often die from a head gasket failure and fracking caused by clogged EGR circuit....but fear not!
    Word is getting around about the EGR circuit and pretty soon there will be a demand for THOSE cats as well.

    Seems to me that THIS is ONE problem that CAN be solved through defunding....... ;)
     
  13. Georgina Rudkus

    Georgina Rudkus Senior Member

    Joined:
    Sep 15, 2018
    3,118
    2,172
    0
    Location:
    Taylors, SC
    Vehicle:
    2012 Prius v wagon
    Model:
    Two
    An oil catch can helps, too.
     
  14. ETC(SS)

    ETC(SS) The OTHER One Percenter.....

    Joined:
    Oct 28, 2010
    7,673
    6,490
    0
    Location:
    Redneck Riviera (Gulf South)
    Vehicle:
    Other Non-Hybrid
    Model:
    N/A
    Yes......they do.
    Every time they are used.

    (*) Pro tip: OCCs are easy to install......which means........;)
     
  15. Miller CAT

    Miller CAT Junior Member

    Joined:
    Apr 21, 2020
    25
    49
    0
    Location:
    San Jose, CA
    Vehicle:
    2013 Prius
    Model:
    Three
    We did thermal testing using our cat shields to ensure that the converter nor the underbody of the car doesn’t get too hot. There’s more information on our website in the Cat Shield FAQ.
     
  16. Georgina Rudkus

    Georgina Rudkus Senior Member

    Joined:
    Sep 15, 2018
    3,118
    2,172
    0
    Location:
    Taylors, SC
    Vehicle:
    2012 Prius v wagon
    Model:
    Two
    Yesterday, I drove 60 miles at various speeds including up to 75 miles on the Interstate. Monitoring the San Gauge 2 revealed no difference between the temperature of the engine with and without the shield. The outside temperature was 95 degrees. The temperature of the engine coolant varied from 188-195. The higher temperature was experienced at higher speed when the ICE was running constantly.

    There is apparently no difference in the regulated temperature between the short original heat shield and the cat shield. The engine air that flows over the catalytic converter flows through the radiator and over the engine first in both situations.

    Apparently the OEM shield, like a spoiler, diverts air under the catalytic converter, since the cat operates more efficiently at higher temperatures.

    Also, I have no way of testing whether the smoother shield under the car might slightly reduce air resistance and increase the vehicle's mileage at speed.
     
    tvirtue and 2012 Prius v wagon 3 like this.
  17. ASRDogman

    ASRDogman Senior Member

    Joined:
    May 29, 2018
    5,883
    3,155
    0
    Location:
    Florida
    Vehicle:
    2010 Prius
    Model:
    Two
    Driving will keep the air flowing so there shouldn't be any difference in temperature.
    It's when you are not moving it would tend to get hotter. But as the heat rises, it draws in the
    cooler air. So it really should make any difference.
     
  18. Georgina Rudkus

    Georgina Rudkus Senior Member

    Joined:
    Sep 15, 2018
    3,118
    2,172
    0
    Location:
    Taylors, SC
    Vehicle:
    2012 Prius v wagon
    Model:
    Two
    Actually, driving with the ICE on generates more heat than the EV mode or with the ICE running in the ECO mode at slower speeds.

    No explanation: just reporting the raw data.
     
  19. ASRDogman

    ASRDogman Senior Member

    Joined:
    May 29, 2018
    5,883
    3,155
    0
    Location:
    Florida
    Vehicle:
    2010 Prius
    Model:
    Two
    Didn't I JUST type that?
    Perhaps I didn't explain well enough. When you are not moving, and the engine is running......

     
  20. ice9

    ice9 Active Member

    Joined:
    May 3, 2019
    581
    343
    1
    Location:
    norfolk va
    Vehicle:
    2018 Prius
    Model:
    Four
    Yes well, when you are not moving, the engine is usually running only intermittently to charge the battery - I am guessing at a duty cycle of perhaps 1 / 10 (engine on to engine off) this would give the cat plenty of time to cool off especially at temperatures at or above 1000 degrees F (cooling becomes more efficient at higher temperatures). The concern is with peak temperature. If damage to the cat doesn't occur until it reaches around 2000 degrees F, I don't see a problem, given intermittent ICE operation. On the interstate, however, max temperature of the cat on the interstate will depend entirely on how efficiently it can dissipate heat when ICE operation is continuous, which in turn depends on air flow around the cat. The question is whether the plate allows adequate airflow when the vehicle is moving. If it doesn't trap or obstruct airflow then it should not be a problem on the highway either.
     
    #40 ice9, Jul 4, 2020
    Last edited: Jul 4, 2020
    Georgina Rudkus likes this.