[Floyd]

I have a 78 RC . I have the feeling both cats(its dual exhaust) restrict the flow because too old maybe full with exhaust stuff. I KNOW I must have those to drive on streets BUT , Does the truck them in order to operate correctly or with other words ..... will I harm the engine or loose power without them two?

p.s I also have a flowmaster on each pipe

any info regarding this matter is very appriciated

Floyd

 

[Slanted_Mind]

Actually, you will likely GAIN power by having the cats "fall off". Of course, this is 100% illegal, and if you have emissions testing in your area, you will not pass the visual inspection. The only vehicles that removing the cats would affect performance on are newer, computer controlled vehicles (OBDII, and maybe even OBDI) because the computer adjusts air/fuel mixture based on O2 sensor readings before and after the cat (at least in certain driving conditions)

Cats on carburated vehicles are simply there to finish combustion that did not take place in the engine. Not having them simply removes an exhaust restriction, and in most cases will increase your emissions.

IMO a properly tuned engine should not need cats to pass an emissions test.

-SM

 

[Floyd]

Hey Slanted Mind, this is exactly the answer I was looking for......
I 'm new to RC , just got it last month.....
My other ride is '66 Plymouth Valiant Signet 2dr - stock
I knew I 've seen the D150 somewhere else ...on the net
Floyd

 

[Slanted_Mind]

Yeah, the pic in my sig is around the net in a few places...I have been to lazy to re-size any other pics I have of it and load them up.

I just noticed you are in CA....you will not get away with removing squat from the original exhaust configuration New cats will help performance if the old ones are becoming plugged. One way to check the existing cats is to drill a small hole before and after the cat in the pipe. The exhaust pressure blowing out these two holes should be roughly the same. If the hole before the cat has much greater pressure than the hole after...the cat is plugged/plugging. If they check out, braze (sp) the holes shut and take a look at your muffler for restriction.

-SM

 

[awyseguy]

Hey Floyd, The slanted mind did forget to mention those "pretend" converters thay many of us use to pass visual inspections, You can either leave the empty shell under there, or drive a piece of pipe through the center.. eother way.. done like that will pass the visual. And as he said.. If well tuned.. You can pass sniffer without them. Cut that pipe.. and knock that crap out of there.. Let us know what you think.
Aaron Wyse

 

[Slanted_Mind]

The main reason I did not mention knocking the guts out of the cats is in CA they have emissions 'rovers' that can tell if a cat is working (hot) as you drive by---and can fine you on the spot if they find alterations. Still a viable option though

-SM

 

[Floyd]

I think in about 4 years or 48 mo. I wont have to go emissions any more...
Just came back from the exhaust shop. The difference is as between night and day.
Now .... I will deal with emissions next week after I tune it up.

 

[awyseguy]

Sorry SM.. I didn't think to notice that he's in the middle of emissions hell. I'm surprised CA doesn't require a C.A.R.B number for the cell phone chargers & fuzzy dice.
Aaron

 

[BrianT]

Actually go to www.summitracing.com and look ofrthe catco converters they are damne near as good as no converter but still 50 state legal to use and you will not lose any HP this way and be legal . You have to keepo the converters where u live Floyd .

 

[Slanted_Mind]

I'm surprised CA doesn't require a C.A.R.B number for the cell phone chargers & fuzzy dice.
Aaron

LMFAO

Hey, I finally ran into another Aaron! And you even spell it right

-Aaron/SM

 

[webbcraft2150]

Here is what I did to get rid of a plugged cat without buying a new one or blowing the "visual" inspection. This was done to a 87 Caddy w/5.0. Carefully removed plugged converter. Ground seam off on one side and pried open, removed all the crap in there, fitted a 2" piece of pipe inside shell and welded it in. Welded shell back together, painted high heat silver and reinstalled. Ran much better (good as a 2ton car with a 307 can). Passed all testing. This procedure is not authorized by any governing body and I will deny any attempt to blame me for the "brown cloud" . Anyway, sold the car, kept the truck. (love those exempt , high GVW trucks)

 

[sig sauer]

hey my name is aaron and spelled correctly too, and is california that picky on their vehicle inspections, what all do you have to go through cause i know none of the old trucks around here(missouri) are really inspected, as long as you have brakes, and wipers, and no real exaust leaks they don't really car how it is run

 

[Slanted_Mind]

If you have ever been to L.A. and taken one breath outdoors, you will know why their emissions laws are so sticky <smog>

FWIW-California has the most restrictive emissions requirements in the country, which is why if a particular aftermarket component is California Air Resources Board (CARB) approved, it is 50-state emissions legal.

-SM

 

[awyseguy]

I've been to L.A. I didn't notice the air.. Well outside of seeing the haze from outside of town/ or up by the observatory. No worse than Phoenix was. Inspections.. I like the ones here now in AL.. Oh that's right.. the most I've ever had inspected is to make sure a VIN matches a title.
I wouldn't mind the state doing safety inspections.. but stay the hell out from under my hood.
As for the name.. of course I spell it right.. I've been using it for years.. I better be able to spell it.
Aaron Wyse

 

[Floyd]

the good thing out here in Ca is that you dont inspect any vehicle 30 years or older and if it is genuine calif. car they are solid as rock no matter how old. My other car is 1966 Plymouth and is emission free. The RC will be that way in 4 years

Floyd

 

[covert_opps]

just go and get new cats - you won't have to worry about it then. it may cost you some $ but won't have to worry about the emissons laws, they will last long enough to get you to the 30 year mark with at least 1 more required smog test, after you become exempt you can do whatever you want.

 

[Floyd]

Just wanted to add that I'm getting new cats installed, I'll be working with it daily and it will be way too loud without cats