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Gut This!

  • Thread starter Thread starter Matts95lt1c4
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M

Matts95lt1c4

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Need info on a possible Cat Convert Gut. I am changing my exhaust system and figure its a good time to gut the cats. Is it worth it? Is it legal?
thanks
 
definetly not legal but do you have emissions?

if yes and caught i think it's a federal fine. if a muffler shop does it for you, good luck finding that. and if a muffler shop ever does work on your exhaust by federal law they are mandated to switch the gutted part out or no cat if you choose that route and replace it with a stock cat. best way around all this hoopla is go buy a racing bullitt style cat (thats legal) but the illegal part is if there is no reason for pulling your stock cat off (because it is still fully functional) then they won't do it. it's a touchy situation in maryland again i don't know your emissions law but here they are strict on this. another way around this is damage the cat as if you hit something and buy the bullitt cat and then take it to a muff shop and say you jacked the car up because of exhaust build up and seen the damage so you "bought" a legal cat to replace it with. by law they will replace it for you with a "legal" cat so do your homework and possibley talk to muff shops in your area and get a feel who "might" do something like this. again this is a sticky subject per area per state basis. with a bullitt style racing cat you'll flow as if a cat wasn't there but still pass emissions for a few hundred bucks and to be safe.

i'm sure others will chime in here on this and help you more.
 
Hey thanks Mad-Mic, I was in annapolis 2 weeks ago, I love it up there. I have a trusted auto shop I will go talk to but im pretty sure I will leave it alone now. I posted a question regarding exhaust upgrades, and am looking for performance upgrades for my vette. I was thinking about the 3 coned k&n air filter claw, and an air foil, along with the exhaust. Anybody out there know anything about removing the screen from my MAS?
thanks
 
Matts95lt1c4 said:
Hey thanks Mad-Mic, I was in annapolis 2 weeks ago, I love it up there. I have a trusted auto shop I will go talk to but im pretty sure I will leave it alone now. I posted a question regarding exhaust upgrades, and am looking for performance upgrades for my vette. I was thinking about the 3 coned k&n air filter claw, and an air foil, along with the exhaust. Anybody out there know anything about removing the screen from my MAS?
thanks

Air foils do nothing but remove $25 from your wallet. Your better off saving the $ and installing a 52mm throttle body.

Removing the screen from the MAF is a so-so idea. The screen is there to smooth the turbulance out in front of the sensor resisistors for a more accurate reading. Pulling it will help top end airflow, but may impact part throttle drivability and MPG. It's your call.

If you bugger the MAF sensor wires pulling the screen, your going to eat a hefty bill for the replacement part. IIRC, there is a snap ring holding the screen in.

Good luck,
Mako
 
Whats the process in getting a new throttle body? Is 52 the better size or will the larger ones work as well? How about price and instalation price?
thanks
 
Matts95lt1c4 said:
Whats the process in getting a new throttle body? Is 52 the better size or will the larger ones work as well? How about price and instalation price?
thanks

Go to www.summitracing.com or www.jegs.com and search for LT1 throttle body. Note that an F-body (amaro/ Trans Am) TB *will not work* on a Corvette, you must buy the more expensive Corvette specific part.

Installing the TB is drop dead simple with basic hand tools. You just move the sensors from the stocker to the new TB and bolt the new on in place of the stock unit.

Takes about 30 minutes start to finish with a break for a slice of 'za and a soda in the middle.

52mm is as large as you can go (and want to go on a stock 350 NA engine) without porting the intake manifold. If you port, you can go to 58mm, which is the max for an LT1.

CYa!
Allen
 
Matt let me know next time you come up i'm about 10 mins from annapolis!

some people remove the back MAF screen and let the front one stay. this promotes alittle better airflow but there is a single wire that runs down the center and if something breaks that wire your in deep doo doo. thats why some don't bother with this procedure. some take both out and report no problems i guess it's up to you. there is a guy around my way, rrubel, that just did this and will help me with mine when i'm ready to start doing some mild mods to my vette. one of his friends Sothpaw has the 3 claw setup you talk about on his 93 LT1. he says it helped alot and was probably one of the biggest mods he done to date. we all go to our local track here at capital raceway during the racing season and have fun thats where i met Sothpaw but i met rrubel from here.
 
mods

Matt,
The claw helps, maybe it gives you .1 sec in the 1/4mi. Is it better
than a K/N with an open lid (cheaper)? I can't say for sure.

I recommend you do the coolant bypass. Also, I have a hyper chip
which turns the fans on early and a 160 Tstat. I don't rec. hypertech but maybe you could try an Ed Wright chip or one
by Jeff on this Forum.

All this is cheap and I got .3 s from the bypass and running the
car cold.

Mic,

So, in MD they really won't change cats unless there's visible
evidence that the originals are busted? No shop?
Do you know if headers will pass here? I'm starting to investigate
headers a bit since they will give me a good torque increase.
 
For those interested...please look up the Clean Air Act through www.epa.gov section 203 and 205.
Which pretty much states it is a Federal offence to alter or remove any emission component from a vehicle under penalty of 25,000.00 per day. Now if the car has over 50k on the meter you can replace the cats or if they are damaged. Other then that it is a no-no to remove or alter them.
Personally I replaced mine on the 85....I did not have enough in the bank to justify taking the chance on a 25k per day fine.
 
Has to be a certified EPA approved converter or you are guilty of altering and subject to 25K per day fine....up to 200K max

http://www.epa.gov/oar/caa/contents.html

Instead of trying to get a few extra horses out of the engine and standing the chance of spending 200 thousand dollars so Uncle Sam can haul your butt into court and jail...why not just replace the cat with a high flow and be done with it. Remember... the reason behind all of this is to clean the air.

The company I used to work for sent me out to San Bernadino to work for a month. Looked out the hotel window and saw nothing but dingy grey sky...welcome to california. I was very shocked to find out one saturday morning that there was actually mountains out the window along with blue sky. I ask what that was all about...it was smog from the city. You see it one time you will leave the cats alone. Besides...think of what we are leaving behind for the kids coming up...is it really worth it for a few extra horsepower?

I think not...
 
no they won't replace the cat with out physical damage. clogged up or banged up they will. headers will pass as long as they are "street" legal. which means basically it has the air lines running from each tube so it can recirculate it. look down at your headers now (shorty stock headers we all have now) and you will see the hoses. thats why most headers are in the 150-300 range and ours is 700-1000 range. a good muff shop can drill holes and cut your old air lines out and refab them into a set of headers in the 150-300 range but i would think the labor would be a bit high. talk to trance LT4 he just did a header long tube conversion last year. i got a good shop up here in pasadena that is willing to work with me as long as i pay cash and say i did all the work myself...lol
 
I know it is illegal in Southern California......is it in your state....be careful..very carefull.....they are watching us....that is the smog nazi's.....
 
Just look for a set of gutted cats for sale.. I know they can be had for 40$ for a 95 Lt1 don't ask how and you didn't hear it from me.. But remmber to save the stock ones for emmissions time..
 
Legal??? No!!!!!!!!!!!!!
But if you do a good job on the gut....no one will know....as long as you have good smog numbers...
So....I guess I'm saying....go for it.......
Watch out for the Smog Nazi's....
tony
 

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