280hp on the dyno??
12-14-2010, 11:35 PM
#23
On The Tree
Join Date: May 2010
Location: North Alabama
Posts: 186
Likes: 0
Received 0 Likes
on
0 Posts
Just a question man but why did you get the emissions turned off if you still have the cats and are running the rear o2's? Maybe I misunderstood you but that is what you said correct? Id just get a vacuum gauge or ask someone who knows how and check backpressure to see if the cats are shot. Now what I'm about to say I'm sure will be contested but if your not running a high horse car then removing the cats is a waste of time and money because your not pushing enough in or out of a stock LS1 to see a big enough restriction through factory cats to cost you any power. Id get some help from your local hot rodder or shop and get the cats checked either by watching the o2's and see what they do, or checking backpressure by whatever means are available to you. If the cats are bad I would REPLACE them. You don't even have to go with a "high flow" cat, just get a direct fit or at the least something of good quality and economical and get it RETUNED so you'll know what the downstreams are doing, seeing as they are catalyst efficiency monitors. You don't have to listen to me just trying to help ya man.
12-14-2010, 11:41 PM
#24
On The Tree
Join Date: May 2010
Location: North Alabama
Posts: 186
Likes: 0
Received 0 Likes
on
0 Posts
Besides in todays times cats aren't restrictive like they were twenty years ago which is why they got a bad name for performance. Fuel quality is better, as well as fuel economy which means less crud getting into that cat. to stop it up. Like I said if they're bad man put new ones on so if you ever do have to pass emissions you won't get a failed state test for having missing cats, and if they're gutted you'll fail too. A good tuner can tune your car to pull the most power, safely....even with cats, that is unless like I said until you start getting higher in power. Whatever way you go chief, good luck, hope you have fun in the process that's what its about.
12-15-2010, 10:26 AM
#25
That's right about where the stock cam decides to nosedive. Not a clogged cat issue, that's just what the stock cam does. My friend's cats were clogged, and his car wouldn't rev higher than 1500rpm without dying. You might just have a weak car or a stingy dyno. What brand was the dyno? Mustang?
12-15-2010, 07:39 PM
#27
On The Tree
Join Date: May 2010
Location: North Alabama
Posts: 186
Likes: 0
Received 0 Likes
on
0 Posts
If it had a catalytic DTC before then yea it MIGHT be the cat, not just the cam or gears. If you know it set that code before it its at least worth checking to see if the cats shot. What exactly are you expecting to get out of a stock 00 model LS1 through an auto. anyway? Guys what should that stock engine put down RWHP on a GOOD dyno?
12-18-2010, 05:05 PM
#30
Launching!
Thread Starter
iTrader: (2)
Join Date: Jul 2009
Location: neversink, ny
Posts: 297
Likes: 0
Received 0 Likes
on
0 Posts
a lot of people have posted here without thinking/reading what i wrote or has been said. a STOCK car makes around 300 on the dyno regardless of the gears it has in it.. therefor the gears aren't effecting it.
2nd.. i had them tuned out so I could pass emissions. i KNOW its bad cats, becuase thats the code that was being thrown before i had them tuned out.
3rd. IM going to replace them with off road pipes becuase I have big plans for the car so might as well do it now.
lastly.. i was simply asking if clogged cats can cause a 20hp loss.. i know they are the problem i was just surprised it was that much of a loss
thanks for the help those who actually read
2nd.. i had them tuned out so I could pass emissions. i KNOW its bad cats, becuase thats the code that was being thrown before i had them tuned out.
3rd. IM going to replace them with off road pipes becuase I have big plans for the car so might as well do it now.
lastly.. i was simply asking if clogged cats can cause a 20hp loss.. i know they are the problem i was just surprised it was that much of a loss
thanks for the help those who actually read
12-20-2010, 09:45 PM
#33
On The Tree
Join Date: Sep 2009
Location: Huntsville, AL
Posts: 197
Likes: 0
Received 0 Likes
on
0 Posts
Hollowing out a cat is a no no. Not only are they worth $100+ a piece because of the metals contained within. But also when you do hollow the cat, it creates turbulance within the gutted cats effectively slowing the the flow of gases through the exhaust system; reducing horsepower and mpgs. (If mpgs matter at all to the owner)
Now, if you can substantiate your claims on mpg and hp I'll believe you, but until then I don't think you have a very good argument. The temporary widening of the exhaust path would be there regardless of the presence of the cat material in turn causing the turbulence you mention.
12-20-2010, 10:01 PM
#34
Now, if you can substantiate your claims on mpg and hp I'll believe you, but until then I don't think you have a very good argument. The temporary widening of the exhaust path would be there regardless of the presence of the cat material in turn causing the turbulence you mention.
12-21-2010, 02:38 PM
#35
On The Tree
Join Date: Sep 2009
Location: Huntsville, AL
Posts: 197
Likes: 0
Received 0 Likes
on
0 Posts
I will believe you if you can come up with some proof. Until then? You're just speculating.
Now, if you're trying to say that an empty cat is causing a loss in power and efficiency compared to a straight pipe of constant diameter I'd wholeheartedly agree, but you aren't. You're saying that a pipe of varying diameter is less efficient than that exact same pipe of varying diameter with a restrictive element stuffed into it. That just doesn't add up.
Now, if you're trying to say that an empty cat is causing a loss in power and efficiency compared to a straight pipe of constant diameter I'd wholeheartedly agree, but you aren't. You're saying that a pipe of varying diameter is less efficient than that exact same pipe of varying diameter with a restrictive element stuffed into it. That just doesn't add up.
