Smog Check Cobb DP

[sidekick]

It's as simple as this: Aftermarket catalytic converter? Fail visual. Sniffer w/ aftermarket DP? Fail, unless the cat is BRAND NEW. And I mean like you put it on a few days ago.

E85 can help, but the problem is that aftermarket cats only get rid of 2 of the 3 contaminants that the sniffer is looking for. So, even brand new, you may not pass on 1 out of the 3 areas tested. There are corvette guys who claim to have passed the sniffer completely catless with a few gallons of E85, but who knows if that's bullshit or not. You do need to tune for ethanol, but keep in mind that the ECU has the ability to add or pull about 25% fuel, so if you stay within that range with an ethanol mix, you will be fine if you only plan to run one tank.

Is that enough help for you? Now go buy some god damn fuel pump internals.

[keymaster]

I'm never going to put a DP on my car, simply because of the CARB rules...it's too much pain to swap in and out every two years. Yes, it means I'll never have the fastest Speed around, but I can live with that. If you have a CARB number on an intake they have to pass you...I'm waiting to see if that's actually true with my intake.

OP, instead of being upset, you could say "thanks for the advice, I know about it but I'm being careful" instead of being grumpy. That's all people are doing, trying to help you out. The rest of you, it's his car to do with as he pleases...even if you think it's stupid and he'll blow up any day now, you just gotta shrug, because you can't make anyone do what you think they should, even if it's good for them.

Oh, almost forgot...do your emissions testing in the morning, there is less crap in the air which means you are pulling cleaner air into the car. The one time I had a bad test with my old car (passed but barely) was when I went in the afternoon, every other time the car was at the bottom of the scale. Also, try to drive there on the freeway, that helps to burn some crud out before testing.

[heeltoe]

Originally Posted by sidekick It's as simple as this: Aftermarket catalytic converter? Fail visual. Sniffer w/ aftermarket DP? Fail, unless the cat is BRAND NEW. And I mean like you put it on a few days ago. E85 can help, but the problem is that aftermarket cats only get rid of 2 of the 3 contaminants that the sniffer is looking for. So, even brand new, you may not pass on 1 out of the 3 areas tested. There are corvette guys who claim to have passed the sniffer completely catless with a few gallons of E85, but who knows if that's bullshit or not. You do need to tune for ethanol, but keep in mind that the ECU has the ability to add or pull about 25% fuel, so if you stay within that range with an ethanol mix, you will be fine if you only plan to run one tank. Is that enough help for you? Now go buy some god damn fuel pump internals.

finally awesome info, i was hearing that the cobb cats at 2-way cats so technically if there was a 3-way high flow cat then it should solve the DP problem right?

will do fuel pump next on list ..

[heeltoe]

Originally Posted by keymaster I'm never going to put a DP on my car, simply because of the CARB rules...it's too much pain to swap in and out every two years. Yes, it means I'll never have the fastest Speed around, but I can live with that. If you have a CARB number on an intake they have to pass you...I'm waiting to see if that's actually true with my intake. OP, instead of being upset, you could say "thanks for the advice, I know about it but I'm being careful" instead of being grumpy. That's all people are doing, trying to help you out. The rest of you, it's his car to do with as he pleases...even if you think it's stupid and he'll blow up any day now, you just gotta shrug, because you can't make anyone do what you think they should, even if it's good for them. Oh, almost forgot...do your emissions testing in the morning, there is less crap in the air which means you are pulling cleaner air into the car. The one time I had a bad test with my old car (passed but barely) was when I went in the afternoon, every other time the car was at the bottom of the scale. Also, try to drive there on the freeway, that helps to burn some crud out before testing.

thanks for the advice lol. test pipe!! easy to put back in should of done that the first place if i know the super expensive cobb dp is not going to pass smog.

[himurax13]

Originally Posted by heeltoe finally awesome info, i was hearing that the cobb cats at 2-way cats so technically if there was a 3-way high flow cat then it should solve the DP problem right? will do fuel pump next on list ..

Let me restate what I have already said.

You should fail visual unless you have stock downpipe.

You might be able to pass the sniffer with 4 gallons of e85 in your tank but you should drive the car around for 30 minutes and leave it running until after the test is over.

Putting the stock downpipe and midpipe back on will pretty much ensure that you will pass and it will probably eliminate the need for hpfp internals for now.

Sent via smokey turbo.

[heeltoe]

Originally Posted by himurax13 Let me restate what I have already said. You should fail visual unless you have stock downpipe. You might be able to pass the sniffer with 4 gallons of e85 in your tank but you should drive the car around for 30 minutes and leave it running until after the test is over. Putting the stock downpipe and midpipe back on will pretty much ensure that you will pass and it will probably eliminate the need for hpfp internals for now. Sent via smokey turbo.

have u tried putting 4 gallons of e85 in ur car when its not tuned for it?

[sidekick]

Originally Posted by heeltoe have u tried putting 4 gallons of e85 in ur car when its not tuned for it?

It will work. Look at it this way. We know that 85% ethanol requires about 30% more fuel for a given amount of airflow/power. A 4 gallon mix in a MS3 will put you at about 30% ethanol content, so that will require about 9% more fuel than 91. The ECU will have no problem adding 9% fuel via LTFTs and STFTs. I would suggest tuning for it if you plan to run an ethanol mix, but 1 tank should not fuck your couch.

[himurax13]

Originally Posted by heeltoe have u tried putting 4 gallons of e85 in ur car when its not tuned for it?

I have had 4 gallons of it in my tank on a 91 tune because I was checking for knock. Gas mileage suffered slightly.

Sent via smokey turbo.