Cat guts removal

It's just a six

Super Member
Re: Cat guts removal

There is a big difference between a normally aspirated engine & a engine w/a turbo while using a cat.

Not really a good comparision IMO.

Between running a cat & not running a cat on a turbocharged engine,,,the difference is day & night.:tup:
 

2500avalanche

Well-known member
Re: Cat guts removal

I know alot of guys like to remove or gut a cat for stricly race vehicles but you can keep your truck emmisions legal with a Random Technology Metal Matrix cat and keep the HP numbers where they need to be. I dynoed my 97 GMC LS6 without the cats and then installed a set of Random Tech Metal Matrix cats and there was no change in HP or torque and I didn't have to smell unburnt gas anymore. I know Dave over at Random if anyone's interested in a group purchase. They're pricey but worth it when you want to keep CFM's flowing. Here's the Sy/Ty part number 192-25009 but you can go universal with this one if you like 141-30000- 3" inlet/outlet. There's also 151-40000- 4" inlet/outlet. Just thought I'd add this to the thread.

Where did you order that 3" cat from? Summit? Thanks in advance for that info, I need it!:tup:
 

It's just a six

Super Member
Re: Cat guts removal

I have seen some of the Evo's owners do before and after testing with 100 cell cats and only lose 5 hp at 400hp level.

That is only part of the picture.

You will lose the ability to build as much boost when using a low stall converter.

If you can hardly build boost w/no cat,installing a cat will make it worse.

Turbo will spool up slower,hence slow down your 0-60 ft time & so-on.,

Cat converters are :tdown: :tdown: in my performance book.

:2cents:
 

2500avalanche

Well-known member
Re: Cat guts removal

That is only part of the picture.

You will lose the ability to build as much boost when using a low stall converter.

If you can hardly build boost w/no cat,installing a cat will make it worse.

Turbo will spool up slower,hence slow down your 0-60 ft time & so-on.,

Cat converters are :tdown: :tdown: in my performance book.

:2cents:
So, would it be worth the time to purchase a 3" magnflow cat, gut it, and put it on? Just curious. The truck I am getting on Friday is tuned for no cat, and I am required to have one in PA... Any help would be great
 

UR50SLO

V6+2=LSXCamaro
Re: Cat guts removal

The purpose of a converter is to burn the Unburnt fuel the inefficient engine does not. There is no other reason to have one.
The more power you make and the more effecient you make the engine in using all the fuel injected the less you'll need the converter anyway.
The best restriction in the exhaust for a turbo car is NO restriction. :)
~Scott
 

Nitrous

New member
Re: Cat guts removal

You can order Random Tech through Thunder Racing, I wouldn't waste the money on Magnaflow cats.

My main reason for mentioning the Metal Matrix cat is because of emmisions and smell not HP gains. I do agree that if you're trying to achieve max HP you don't need a cat. I know with RT high flow cats the dyno nubers on a turbo car gained 10 + hp over the stock converter and I'm sure the Metal Matrix will prove more than that since they flow more CFM's. I'm not trying to steer anyone in the wrong direction but wanted to mention Random Tech if anyone wanted to keep a super high flow cat. I know they last because I've sprayed quite a bit of Nitrous through mine and they've long outlasted the crappy Magnaflows I once had.....................
 

2500avalanche

Well-known member
Re: Cat guts removal

You can order Random Tech through Thunder Racing, I wouldn't waste the money on Magnaflow cats.

My main reason for mentioning the Metal Matrix cat is because of emmisions and smell not HP gains. I do agree that if you're trying to achieve max HP you don't need a cat. I know with RT high flow cats the dyno nubers on a turbo car gained 10 + hp over the stock converter and I'm sure the Metal Matrix will prove more than that since they flow more CFM's. I'm not trying to steer anyone in the wrong direction but wanted to mention Random Tech if anyone wanted to keep a super high flow cat. I know they last because I've sprayed quite a bit of Nitrous through mine and they've long outlasted the crappy Magnaflows I once had.....................

Thanks for that info. I will check them out. what did a 3" run you?
 

It's just a six

Super Member
Re: Cat guts removal

So, would it be worth the time to purchase a 3" magnflow cat, gut it, and put it on? Just curious. The truck I am getting on Friday is tuned for no cat, and I am required to have one in PA... Any help would be great

I would just run a gutted 3" cat,if you can find a muffler shop, they throw away these bad ones,or sell for scrap or source a used bad cat w/a 3" inlet & outlet gut that & install it.

I am pretty sure it will run fine w/a cat,but not as good IMO.
 

SY2455

70's Veteran
Re: Cat guts removal

I know alot of guys like to remove or gut a cat for stricly race vehicles but you can keep your truck emmisions legal with a Random Technology Metal Matrix cat and keep the HP numbers where they need to be. I dynoed my 97 GMC LS6 without the cats and then installed a set of Random Tech Metal Matrix cats and there was no change in HP or torque and I didn't have to smell unburnt gas anymore. I know Dave over at Random if anyone's interested in a group purchase. They're pricey but worth it when you want to keep CFM's flowing. Here's the Sy/Ty part number 192-25009 but you can go universal with this one if you like 141-30000- 3" inlet/outlet. There's also 151-40000- 4" inlet/outlet. Just thought I'd add this to the thread.

I just talk with Random Technology and they said that they are no longer, but they may be able to make them again if there is a interest in them.
 

Brassmonkey

Cruzin' Mel Man

Don W.

Stab it and steer it
Re: Cat guts removal

I would not buy a Maganaflow cat. 2 years back I spent a ton of time and some $$ trying to pass smog on what turned out to be a bad (Magnaflow) cat that was only a few months old at the time.
 

nello

Active member
Re: Cat guts removal

oooh, i like that. That's the one thing I'm afraid of in california. Getting pulled over, for any reason, and a cop seeing I have no CAT. The stuff under the hood I can explain, but no cat is a sure trip to the smog referee. Nice find.
 

dgoodhue

BuSTeD 4.3
Re: Cat guts removal

I just talk with Random Technology and they said that they are no longer, but they may be able to make them again if there is a interest in them.

The random technology SyTy catalytic converter is also a 2 1/2" in/2 1/2" out conveter to fit the stock DP.
 
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