Prius owners with Catalytic Converter protector! Help other Prius Owners find the right protector.

I know this is in the Gen2 section, but here are pics of the Cap City Muffler plate installed on a:

Gen3:



Gen4 / Prime:



hard to know if someone has investigated .

Use rivets and it will be a good solution.

But with these plates installed, it should deter.

 

I like the cat-security model.

You can uninstall your OEM cat and sell it....buy a $150 aftermarket cat AND the cat shield...... and have them both installed (or, BETTER, DIY) and you might even make a buck or two.....
The emissions folks will not be able to tell what kinda converter you have behind the aluminum cat shield.

The cat shield might also make it harder for you to accidently start a grass fire by pulling off the road if you have car trouble.....NOT that this has ever happened out on the left coast.



The cable converter lock looks to me like a hard pass, unless you think that the VET will hassle you about not being able to see the cat behind the aluminum plate.
I'm thinking that it would be cooler, and it would probably deter a very lazy thief, but if I were stealing cats for $250 a pop, and I already had the car jacked up, an over-watch positioned, and the get-away van idling nose out......It looks to me like I could cut the cat out anyway and take the lock and the cat both....and I might make the attempt anyway.
Even if I'm unsuccessful....you'd still have to pay for a repair.

I'd have to see one installed to know for sure.

As ALWAYS
YMMV

 

My daughters gen II factory catalytic converter was stolen the other night in Seattle and I ordered Walker cat and resonator section plus the CCM plate. They cut both ends of the cat out. I was sure I was going to have to order bolts, springs and that expensive exhaust gasket. I was surprised they didn't use a pipe cutter and 14mm socket with ext and ratchet. Would have been easier.

After looking at the way they cut the front of the cat pipe behind the flange the CCM plate may slow them down. I know these replacement cats are not the ones they want as much but none the less I will put the shield on my gen II and make one out of extra 16 gauge sheet metal I have in my shop for her car. I will beef them both up a bit during install. I will also weld round stock to the pipes they had cut and make some exhaust bolts with wheel lock nuts welded on them. To get the cats off either car next time would be a major pain in the a$$.

 

Hello all, this is my first post. I bought a 2009 last august with only 42K miles on it and had my cat stolen out front of my house 3 weeks later. Only then did I learn what a lucrative target I had acquired. I live in California so I had to get an oem but luckily I have always kept comprehensive insurance on my vehicles. Since insurance was footing most of the bill I opted to take it to a dealer. With $500 deductible and a pro-rate on the age of the original cat I still had to shell out $750, but after reading some other stories I consider that getting off easy. As a bonus the dealer ran my VIN and had records on all the maintenance ever performed on my baby. It turns out that the car was always dealer maintained and well taken care of. They offered to install a cat shield for an extra $600 but since I am a metal fabricator by profession I decided to see what I could come up with on my own. I'm also lucky that I have a really cool boss who is in to cars, and we happen to have a lift in the back of the shop.

Once I got a good look I decided to weld some bars along the exhaust pipes, which I understand is a common thing to do. We had a variety of left over material so I opted for 304L stainless steel, not just for corrosion resistance but also because it is more difficult to cut. I have wrecked many a saw blade & cut off wheel on that stuff over the years. In the area between the cat & resonator which seems to be where they most often cut I used square stock (1/2") and doubled it up. Toward the rear of the system I switched to round because it is easier to form to the contours of the pipes. I also found a piece of 16 ga. stainless sheet laying around that I was able to form up into a guard of sorts for the flange bolts up front. I have no idea what they are for but there were 3 threaded studs on the bottom of the car that I ended up using to attach it. I doubled up the nuts and jammed them pretty well so it shouldn't come loose. Now, at least, whomever tries to come unbolt it will have eight fasteners to remove instead of two, and they'll have to figure out on the fly what size socket to use for the guard. So far everything is still in place, but I have to assume my car gets jacked up and looked at every month or so. Sorry it's not my prettiest work. I did the mods while it was still on the car and used a portable tig welder that had thumb control instead of a pedal. It was cumbersome to use but those ugly tacks should hold. I also used stainless filler wire, obviously.

 

• Looks good to me. I doubt any would be thief will be critiquing your welds. That square stock would be a bugger to cut with a saws all . On my daughters gen II they cut in front of that cross member which is a straight shot at the pipe with a saws all. I am going to rig up some protection from that area.

 

Great DIY work!

Nice having a good boss, huh?
2 things Ive always wanted to learn:
Welding and masonry.

Looks like pretty good work from here.....

 

Nice work flea.

only thing that would worry me is you have blocked all the heat venting from the exhaust manifold. It’s now trapped in the engine compartment.
It may get extremely hot in there now.

the stainless steel bars were enough.

 

He did an excellent job with the welding and fabrication. But trapping the exhaust manifold is not good. It gets really hot. It now has no place to vent.

I would drill some vent holes in the bracket.

 

I gave some consideration to that and it's why I didn't make it larger so it went further up around the pipe. I figured there was probably enough open space above it to maintain some airflow. Do you really think it's too closed in? It wouldn't be difficult to pull it off & drill some holes just to be safe. The car is like new and I really don't want to mess it up.

 

You could do some testing on a hot day. Multimeter with a temp probe and drive around town and remove shield and test drive again and compare readings. I don't think there would be a problem driving at highway speeds but you can test it.

I am working on daughter's gen II now and area which is problem is in front of that crossmember. That's where they cut her pipe with sawzall. I made mounting bolts with wheel locks welded to the heads of the bolts, and will weld round stock to pipe behind the mounting flange. A thief could still use 12" blade on Sawzall and cut the two bolts between the flange and header. I am making a sheet metal cover that covers around the bottom of mounting flange of exhaust header and cat. All this plus a cat cover with rods welded at the areas that get cut should be fine. I am prototyping this car to get it figure out for my pruis which has factory cat on it.

 

Just drive around a bit then open the hood. If you get hit with a wave of heat when you open the hood well then you know.
Sniff around the back of the engine see how hot it is back there.
It’s winter so shouldn’t be too bad. Summer will get you though I suspect.

my fear is the op will not be driving it but the daughter.

 

Seems like it would be easier for me to just drill some holes to be safe rather than deal with the testing of different scenarios. I hadn't really thought about stop & go traffic in the summer so I think it's a valid concern. I really appreciate the input and this forum in general. Thanks a lot.

 

I thought air was a poor conductor of heat and the plate with a larger surface area would actually be a better conductor acting like a cooling plate under a computer?


iPhone ?

 

I don't see much clearance where that plate is cut for the pipe to pass through.

The engine and transmission mounts are flexible, and the pipe will move downward under acceleration.

This could result in contact and noise transmission to the floor pan under strong enough acceleration, or eventually damage to the pipe.

Years ago in a different vehicle, I had a local transmission shop drop and reinstall my transmission one time to save the trouble of doing it myself, and when they reinstalled it they replaced a skid plate backwards under the transfer case. That plate had a lip on one edge, and when backwards, the lip was right under the exhaust. It did not touch while they had it up on the lift, but it touched and put pressure on the exhaust afterward whenever I accelerated. Within about a year, that catalytic converter broke off at the pipe in front.

 

yes I think some holes would really help. An exhaust manifold gets incredibly hot. You have trapped it’s outbound air flow.
That’s why you have not seen any guards built like that,

as far as shencks nutty statement that metal cover is going to get extremely hot. But won’t help cool the exhaust mani as the exhaust just keeps coming.
The engine block is its best heat sink so the engine may get extreme hot too. This is a job for a IR thermometer.

I think you could handle anything that would come up if you were driving the car but with a daughter......

Take it out in the highway and drive it hard for a half hour then pull right over
Open the hood and put your snoot in the back of engine and see how hot it is.
If you get hit with a wave of heat when you open the hood then you know it won’t survive long in a California summer.

nice fabbing though.

 

Thanks for all of the compliments & advice. This is a great forum. I have lurked for 5 months or so and learned a ton about Prii.

PaulSchenk, I see where your going with that line of thought, but I think if it were to work the heat would only be transferred to the cross member through the bolted connection, and inefficiently at that. Stainless has terrible thermal conductivity (which actually makes it kind of easy to weld), but it would be the worst metal to use for a heat sink. It might work if the guard were made of aluminum, but then it would be a weaker guard, and the crossmember isn't where I would want the heat to go anyway.

ChapmanF, You are correct and that did occur, especially when I was starting from a stop sign and turning right. There is one particular intersection in my neighborhood where I would hear rattling every time I went through because I had to turn right and accelerate up a hill. I pulled the guard off and could see some marks on the pipe where it was rubbing so I ground out some more material in that area and re installed it. It hasn't been a problem since then. I definitely underestimated how much the exhaust moves around under different loads, but it makes sense. Motor mounts aren't solid.

edthefox5, I don't have an IR thermometer although shame on me because I am a welder and should have one. I've always used an old-school thermocouple attached to a Klein multi tester for checking weld preheat temps whenever I've needed to. I think it's about time for me to convince my boss that we desperately need one.

I'm going to pull the guard off & drill some holes this weekend in any case, but I think you made a good suggestion. I would like to monitor the temps as we get into the summer, especially if this year is anything like 2020 was.

 

good luck you did a great job on it lots of good work. I wish you well and only advise to help you.