Emissions after MSD Ignition/EFI

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scenic760

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Hopefully someone can take a look at this and let me know if it makes sense as I know very little about this stuff!

So I'm using an Atomic EFI system, MSD 6AL box and MSD 85551 distributor. All of the items have a CARB exemption so in theory I should be able to pass smog check with all the items installed...theoretically.

I was going back through trying to decipher all the emission hose/vacuum routing and it seems to me that a decent portion of the stuff gets deleted by using the EFI and electronic spark control?

It looks like EFI knocks out the need for the vac lines to carb and I can grab vacuum sources from the manifold for the EGR and EFE TVS valves? In addition I think the EFI/6AL would eliminate the need for a decel valve?

Does this look correct? If it does, hopefully the smog guys sees it that way too!!
 

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scenic760

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Well after doing some reading it looks like I already have a flaw in my plan...it seems as though the EGR will need ported vacuum..which the Atomic does have a provision for...
 

Frankenchevy

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You may want to reach out to a smog referee. In my experience, they can be helpful.
 

scenic760

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You may want to reach out to a smog referee. In my experience, they can be helpful.

I always thought that you had to make an appointment with one AFTER you failed a smog test? Can you just cold call them for questions?

Also with a new engine, wouldn't it need to be broken in to pass?
 

scenic760

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You may want to reach out to a smog referee. In my experience, they can be helpful.
I just got off the phone with the referee call center and they were definitely nicer than I thought they would be!

She told me that if I'm doing a "direct replacement" which is what an engine rebuild would be vs doing an "engine change" I do not need a referee, just a regular smog test.

I guess that puts me back to hoping I get it right...
 

scenic760

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Yet another question....it looks like both of the vacuum sources to the EGR TVS are needing ported vacuum? The EFI only has one ported source so hopefully it's acceptable to just run one line and tee off connections?
 

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skysurfer

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You're over-thinking this. I don't think there's a smog tech alive that's going to trace vacuum lines to see if it matches the diagram. A quick under-hood inspection will just verify the oem components are there and if it's running clean at the tailpipe, you're golden. These stations net about $50 for a test and there's NO incentive to crawl all over the engine bay looking for a misrouted vac hose. The faster they test your truck the sooner they're on to the next one. Time and money is the name of the game. Make your engine bay appear as unmolested as possible, little things like having the correct heat-riser tube going to the air cleaner will have the inspector thinking there's no reason to dig deeper. Just keep your mouth closed and don't hover around watching the test like an expectant father in a maternity ward. I tested a LOT of cars back in the day and the more nervous an owner appeared made me suspicious as to what they were trying to sneak past me.
 

scenic760

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You're over-thinking this. I don't think there's a smog tech alive that's going to trace vacuum lines to see if it matches the diagram. A quick under-hood inspection will just verify the oem components are there and if it's running clean at the tailpipe, you're golden. These stations net about $50 for a test and there's NO incentive to crawl all over the engine bay looking for a misrouted vac hose. The faster they test your truck the sooner they're on to the next one. Time and money is the name of the game. Make your engine bay appear as unmolested as possible, little things like having the correct heat-riser tube going to the air cleaner will have the inspector thinking there's no reason to dig deeper. Just keep your mouth closed and don't hover around watching the test like an expectant father in a maternity ward. I tested a LOT of cars back in the day and the more nervous an owner appeared made me suspicious as to what they were trying to sneak past me.
I appreciate the insight my man!

I have definitely heard some horror stories about the one smog tech who is going to save the world one charcoal canister hose at a time..

I was hooking up my routes this afternoon and I was resolved to the 'it is what it is" school...all I can do is take it down, have it inspected and either have the holy water sprinkled on it or cast into the lake of fire...
 

timbritton

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I don’t have to worry about emissions. I just want to stop raw fuel blowing onto the road before I use it. Or possibly roasting my toy.
 

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Just an opinion, but, seems like the improvements you have done will make it run cleaner than original spec. I don't see how you could possibly fail. I also would not offer any unsolicited info that is not asked for. Going when they are busy gives them less time to "FIND" things also.

I dealt with the So Cal. smog referee in the late 80's, they were pretty easy to get along with, I had to hit their spending cap to satisfy them with a 1978 Doge Magnum with a 1974 engine in it. Could not quite get it into spec for that year to pass smog.
 

scenic760

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Just an opinion, but, seems like the improvements you have done will make it run cleaner than original spec. I don't see how you could possibly fail. I also would not offer any unsolicited info that is not asked for. Going when they are busy gives them less time to "FIND" things also.

I dealt with the So Cal. smog referee in the late 80's, they were pretty easy to get along with, I had to hit their spending cap to satisfy them with a 1978 Doge Magnum with a 1974 engine in it. Could not quite get it into spec for that year to pass smog.

Some of the best advice I ever received from this forum was unsolicited so I'm all for it!

I don't think I'm going to have a problem passing through the tailpipe but I think my inexperience in dealing with this has gotten me paranoid. All of the deletes I made on my hose diagram were directly related to vacuum controlled carb/distributor which all left the engine bay with the EFI. It makes perfect sense to me but I have heard horror stories...

One of those stories being my next door neighbor and his late dad's 1984 Mustang GT...he has spent about $4000 (yes, 3 zeros) trying to get it to pass smog so far and every time he has been told it's a carburetor issue... I felt bad showing him the EFI setup I put on because he looked at doing it and it's only CARB approved for GM vehicles...no doubt it would produce a way cleaner exhaust than ANY carb you would put on that car but because it doesn't have a little sticker, he can't use it...silliness
 

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Well after doing some reading it looks like I already have a flaw in my plan...it seems as though the EGR will need ported vacuum..which the Atomic does have a provision for...
The egr will need ported vacuum and a thermo vacuum valve to disable it on cold start and warm up.
 

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