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79 Alfetta GT (Sprint Veloce)
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Discussion Starter #1
Hi,

With all the help we've gotten here, wanted to pass some wisdom back in that might be of help.

We've hyped a 79 coupe's engine to include euro exhaust, which won't pass CA smog. I've seen some posts here about this dilemma, and want to share our solution.

Posts have been about modding the CA air injection manifold to mount to the euro exhaust holes, since the inspection needs to see air injection. We explored this but it seemed very risky. Means drilling tapping the euro air inputs (they do not match US), modding the air manifold, etc. It became plain this could get expensive and even then not work and perhaps ruin existing parts.

So, we designed a sort of swappable exhaust solution. We had exhaust guys build 2 middle sections, one mated to the Euro front pipe, and one to the CA. They actually can swap in interchangeably. And we made it easy to do using V-band clamps at connection to front and the rear tail section. CA middle has a proper CAT, and euro has a nice Magnaflow muffler.

So, when we need to pass smog, we can swap in the manifold, downpipe and CAT middle in maybe 2 hours and then 2 hours more to put the euro back in.

It was pricey (all up ~$1000 parts/labor), but we think it will allow us to pass when we need to and then put the better breathing sections back on.

p.s. we are not installing the air injection pump. Just the hosing to the manifold so it looks like the air system is there. We're banking that they can't see down to the air pump area and would not know what to look for anyway. Wish us luck on that one - we don't want the swap to involve the air pump as well.
 

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You can just take the guts out of the air pump. Then it just becomes a spinning pulley.
 

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You can just take the guts out of the air pump. Then it just becomes a spinning pulley.
Can the SPICA-equipped Alfas of this era pass the CA tailpipe emissions test using this method? In my experience on the Porsche side, engines of this era that are really solid mechanically and/or recently rebuilt can pass the tailpipe test without air injection (these all have Bosch CIS/K-Jetronic, which can be tuned to provide a stable mixture), as can most turbocharged engines, but most do need the extra help of the air pump to get them over the hump. The "period correct" catalysts of this era just don't cut it!
 

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I have no idea about CA emissions.

My brother is a master porsche tech from the who started at the dealer in the 80's. When Atlanta went to emissions. I know that the 911 were passing the tailpipe sniff test at idle. On the ones they had taken the vanes out of the pump. So the pump had basically become an idler pulley.
 

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I have no idea about CA emissions.

My brother is a master porsche tech from the who started at the dealer in the 80's. When Atlanta went to emissions. I know that the 911 were passing the tailpipe sniff test at idle. On the ones they had taken the vanes out of the pump. So the pump had basically become an idler pulley.
Yeah, depends on what the actual emissions thresholds are, though I can't imagine that the Atlanta ones are that different from California standards as that tends to be what sets the bar for other states/regions.

That said, the constantly-running air injection pump is not good for the engine in the long term as it raises exhaust gas temperatures, which eventually cooks the exhaust valve guides, among other things. So, if it is needed to pass an emissions test, there is a possibility that the reinstallation of the belt might be forgotten after that is done :)
 

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79 Alfetta GT (Sprint Veloce)
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Discussion Starter #6
Yeah, depends on what the actual emissions thresholds are, though I can't imagine that the Atlanta ones are that different from California standards as that tends to be what sets the bar for other states/regions.

That said, the constantly-running air injection pump is not good for the engine in the long term as it raises exhaust gas temperatures, which eventually cooks the exhaust valve guides, among other things. So, if it is needed to pass an emissions test, there is a possibility that the reinstallation of the belt might be forgotten after that is done :)
We're going to try to pass both visual and tailpipe without the pump. Visual should pass since all the hosing and air manifold will be there, and we doubt someone's going to go looking for the pump, and even if they do it's very obscured. I've read here that a well tuned motor will pass without air and I believe that and this motor and FI will have <10 miles when they're tested.

If we are somehow asked to put one on, I do like the idea of de-belting it after. We don't want it's contribution, and when we restore the euro header, there will be nowhere for the air manifold to plug in properly anyway.

Thanks everyone for the replies.
 

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We're going to try to pass both visual and tailpipe without the pump. Visual should pass since all the hosing and air manifold will be there, and we doubt someone's going to go looking for the pump, and even if they do it's very obscured. I've read here that a well tuned motor will pass without air and I believe that and this motor and FI will have <10 miles when they're tested.

If we are somehow asked to put one on, I do like the idea of de-belting it after. We don't want it's contribution, and when we restore the euro header, there will be nowhere for the air manifold to plug in properly anyway.

Thanks everyone for the replies.
You might want to get a moving permit and do at least one good break-in drive to seat in the piston rings before you go for the smog check. If the piston rings aren't broken in a bit, you might have excessive hydrocarbon (HC) emissions, which would normally be neutralized by the air pump.

I would also advise pre-checking the emissions at a specialty shop that has a 5-gas exhaust analyzer. We routinely do pre-smog checks for our Porsche/BMW customers. It's a complete pain to have to go to the smog shop 2-3 times or more. Plus you want to make sure your mixture is dialed in for normal driving!

And, if you go the belt removal route, be sure to seal off the pump inlet and outlet and give the pulley a few spins anytime you are under the hood/car. This will ensure it doesn't seize up before the next smog check!
 
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