No More Offroad Mid Pipes?
- Thread starter Cheapskate207
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I actually can't stand to be behind any car without cats, save for those old 60's hot rods. I don't mind, and even like the smell of those. They seem very mild.
Modern EFI cars for some reason really bother me. I know everyone says it's in the tuning, but I find it hard to believe every single efi car without cats is tuned that badly. I have fond memories of being in friends Mustangs back in the 90's in drivethru with people behind us swearing at us due to the fumes. Even today, most often when I get behind a modded car with no cats (even Mustangs) I find myself changing lanes to get away from the smell. I've been behind a few Cat-delete S550's and it just smelled BAD.
My experiment with off-road pipes lasted a few weeks or so before I put the stock pipe back on. I still have the off-road pipe. Maybe i'll hang onto it now
I guess i'm getting older, and maybe a little more hypocritical in my age, but modded cars are starting to irk me, especially when it comes to exhausts and lighting. But then again, when I was younger I did this sort of stuff too.
Modern EFI cars for some reason really bother me. I know everyone says it's in the tuning, but I find it hard to believe every single efi car without cats is tuned that badly. I have fond memories of being in friends Mustangs back in the 90's in drivethru with people behind us swearing at us due to the fumes. Even today, most often when I get behind a modded car with no cats (even Mustangs) I find myself changing lanes to get away from the smell. I've been behind a few Cat-delete S550's and it just smelled BAD.
My experiment with off-road pipes lasted a few weeks or so before I put the stock pipe back on. I still have the off-road pipe. Maybe i'll hang onto it now
I guess i'm getting older, and maybe a little more hypocritical in my age, but modded cars are starting to irk me, especially when it comes to exhausts and lighting. But then again, when I was younger I did this sort of stuff too.
HemiRick
I'd be looking at jacking under the house
I did some research and it appears I'm wrong again. Cats can change the smell as they reduce oxides of Nitrogen. Nitric oxide is a sharp sweet-smelling gas at room temperature, whereas nitrogen dioxide has a strong, harsh odor and is a liquid at room temperature, becoming a reddish-brown gas above 70 EF. Both are reduced or eliminated by a cat.
So why do carbed cars from the 60's and earlier smell differently than modern cars with cats removed.
Tell me i'm not the only one that notices this??
Tell me i'm not the only one that notices this??
- Mar 7, 2002
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The EFI cars run leaner, changing the mix of gases and thereby the smell. It was one of the first things I noticed when I went from carb to TBI on the engine in the Mustang II.
Boostedpimp
Dirt-Old 20+Year Member
If your getting to old to deal with a little exhaust fumes from time to time try some fuel fragrance in grape flavor
- Mar 7, 2002
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But the cherry smells more better.If your getting to old to deal with a little exhaust fumes from time to time try some fuel fragrance in grape flavor
I've been driving a Mustang without cats for 23 years now, and to be honest with you, I'm getting sick of the smell too. It's messed up, because my car no longer requires emissions testing. I'm considering a way to put cats back on the car without killing the power. EFI cars without cats do stink bad.
Kurt
91GTstroked
15 Year Member
- Jun 14, 2007
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And Jegs just had a sale for their off road h pipe for shorty headers. I snagged one up for 120ish shipped. They sold out fast.
And I have long tube headers lol.
And I have long tube headers lol.
- Mar 7, 2002
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Modern 3-way catalysts aren't very restrictive at all. Look at all of the 450hp+ production cars running two or more per bank now.
A catalytic converter is actually in my plans for the 4.6 turbo build for my II.
In searching the web this guy did a dyno before and after deleting cats on his 2018GT
EDIT: won't let me link direct to thread
454HP/420TQ with cats and 467HP/434TQ with them deleted. +13HP, +14TQ. Roughly a 3% gain in power.
EDIT: won't let me link direct to thread
454HP/420TQ with cats and 467HP/434TQ with them deleted. +13HP, +14TQ. Roughly a 3% gain in power.
Decipha
Active Member
I can tell if a car has cats or not just driving behind it. I cant tolerate being in the vicinity of a vehicle with no cats before it affects my breathing.
We build turbo coyotes that make 1000+ rwhp on the stock cats.
We build turbo coyotes that make 1000+ rwhp on the stock cats.
- Mar 7, 2002
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13hp and 14tq is less than can be gained with a handheld tuner while retaining the cats. There's no real reason to delete cats on a modern car. Some of them are so well engineered that you'll lose power from doing it.In searching the web this guy did a dyno before and after deleting cats on his 2018GT
EDIT: won't let me link direct to thread
454HP/420TQ with cats and 467HP/434TQ with them deleted. +13HP, +14TQ. Roughly a 3% gain in power.
Boostedpimp
Dirt-Old 20+Year Member
no cat mid pipe is considerably less weight than the factory mid pipe just to add another angle to it
I'll tell you how to run without cats and not stink up the city, I read on hear sooooo many times how running catless makes the car stink and my car is without cats and I never noticed any stink, (well from the car anyway) and was very surprised to find when I pulled the heads that the spark plugs were only finger tight!! How they didn't fall out I have not a clue, it did have a constant lean code I could never figure out and the occasional cel but again both banks lean, car ran great,
I could get it sideways in first and second.
But it didn't stink!!
So all you gotta do to run without cats and no stink is put the spark plugs in finger tight!
I could get it sideways in first and second.
But it didn't stink!!
So all you gotta do to run without cats and no stink is put the spark plugs in finger tight!
I'm going to figure something out if and when I ever switch to a turbocharged setup. I don't think I want to run cats with the nitrous setup.
Kurt
All this talk of cats and off-road pipes got me wondering what it must have been like to walk down a busy street in a crowded city in 1970 with all the leaded gas and lack of catalytic converters.
ppost
Member
Lots of pictures of the smog, but I’m wondering about what the assault on the senses must have been like at ground level.plenty of pics of the ole smog days
