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Smog Manifold
Posted by: MonzaDave ()
Date: April 18, 2020 01:53PM

I'm putting my '69 140hp Corvair back together. Should I replace the smog manifolds with non-smog. How much difference would it make?

Dave Keillor
Rochester, MN

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Re: Smog Manifold
Posted by: joelsplace ()
Date: April 18, 2020 02:01PM

Did they make 140 smog manifolds? I've never seen those.

Joel
Northlake, TX
5 Ultravans, 114 Corvairs and counting...

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Re: Smog Manifold
Posted by: MonzaDave ()
Date: April 18, 2020 02:21PM

joelsplace Wrote:
-------------------------------------------------------
> Did they make 140 smog manifolds? I've never seen those.

Yes, they have tubes for the air injection.

Dave Keillor
Rochester, MN

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Re: Smog Manifold
Posted by: Wills69 ()
Date: April 18, 2020 02:31PM

I think they did use smog manifolds on later 140s.
My friend has a low mileage 69 140 that someone de- smogged.
There is plumbing from the exhaust coming into the engine compartment that was capped off.
Also, those exhaust manifolds have tubes going into the head exhaust tubes to
inject extra air to burn off more gas.
I wouldn't mess with it unless your racing .

Will
Grayslake IL
69 500

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Re: Smog Manifold
Posted by: MonzaDave ()
Date: April 18, 2020 02:34PM

Wills69 Wrote:
---------------
> I wouldn't mess with it unless your racing .

Smog system has been removed and stored.

Dave Keillor
Rochester, MN

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Re: Smog Manifold
Posted by: Colorsarge ()
Date: April 18, 2020 03:43PM

I asked about this a couple of months ago and one member replied that the combination of pre smog manifolds and a pre smog distributer made a noticeable difference. I have since done this change to my Calfornia built 66 but have been solving other issues, so, can't really comment on the results yet.

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Re: Smog Manifold
Posted by: john.jackson ()
Date: April 18, 2020 05:03PM

Yes, my 69 140 Monza Convertible has all the original factory smog equipment.

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Re: Smog Manifold
Posted by: Vairismo ()
Date: April 18, 2020 06:47PM

Think I may have a set from my '68. We assume that Minnesota doesn't care? Don't some (maybe all) 68-69 140s use the 95 horse camshaft with the retarded gear on the crankshaft?
Haven't heard lots of stories of regretting removing them. Have to wonder if it would make any difference (later on) to a serious 'collector' to have the original stuff in place.

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Re: Smog Manifold
Posted by: MonzaDave ()
Date: April 18, 2020 07:03PM

Vairismo Wrote:
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> Haven't heard lots of stories of regretting removing them. Have to wonder if it would make any difference (later on) to a serious 'collector' to have the original stuff in place.

I have all the smog parts, including the manifolds, so the car could be returned to "stock" quite easily. No, Minnesota doesn't care.

Dave Keillor
Rochester, MN

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Re: Smog Manifold
Posted by: RexJohnson ()
Date: April 19, 2020 10:31AM

If you are saving the smog system in a box for later then I would put the whole system in the box. If you leave the smog manifolds on there will holes to plug that you would not have to do with non smog manifolds. Plus if the smog manifolds are in good shape they would still be in good shape if the system was to be put back on.

RJ tools
Salem,Oregon

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Re: Smog Manifold
Posted by: MonzaDave ()
Date: April 19, 2020 10:50AM

RexJohnson Wrote:
-------------------------------------------------------
> If you are saving the smog system in a box for later then I would put the whole system in the box. If you leave the smog manifolds on there will holes to plug that you would not have to do with non smog manifolds. Plus if the smog manifolds are in good shape they would still be in good shape if the system was to be put back on.

Okay, let me be clear. I bought the car new in 1969. The smog (AIR) system was removed not long afterward -- as much for spark plug access as anything else. I put the AIR pump and ancillaries in a box and it still resides therein. I did not remove the manifolds, but plugged the holes where the air is injected into the manifold -- and the plugging is easily reversible.

Fast forward to now. The car is disassembled and the manifolds are sitting on a shelf.

My question was and still is: Would there be any performance boost if I were to install non-smog manifolds.

Dave Keillor
Rochester, MN

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Re: Smog Manifold
Posted by: RexJohnson ()
Date: April 19, 2020 12:34PM

As far as a performance gain I would no. You probably couldn't feel any difference but it would clean up the engine compartment a little bit.

RJ tools
Salem,Oregon

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Re: Smog Manifold
Posted by: MonzaDave ()
Date: April 19, 2020 12:39PM

RexJohnson Wrote:
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> As far as a performance gain I would no. You probably couldn't feel any difference but it would clean up the engine compartment a little bit.

No it wouldn't clean up the engine compartment. As I said, the AIR compressor and ancillaries were removed in 1969. The topic is the exhaust manifolds.

Dave Keillor
Rochester, MN

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Re: Smog Manifold
Posted by: Seth Emerson ()
Date: April 19, 2020 02:13PM

Dave - the smog manifolds, including the tubes have to cause a bit of flow disruption in the exhaust flow, and have a performance impact. I would remove them, and replace them with pre-smog 140 manifolds, or, if you want to improve the flow a bunch, Dave Kostich internal mount manifold/headers.

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Re: Smog Manifold
Posted by: MonzaDave ()
Date: April 19, 2020 02:47PM

Seth Emerson Wrote:
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> Dave - the smog manifolds, including the tubes have to cause a bit of flow disruption in the exhaust flow, and have a performance impact. I would remove them, and replace them with pre-smog 140 manifolds, or, if you want to improve the flow a bunch, Dave Kostich internal mount manifold/headers.

That's what I thought, but . . . The manifolds are off, so it won't be a big deal to replace them with non-smog manifolds -- just have to get some. I want to keep the car basically stock, but tell me more about the Dave Kostich headers. Maybe Mr. Redd?

Dave Keillor
Rochester, MN

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Re: Smog Manifold
Posted by: American Mel ()
Date: April 19, 2020 07:10PM

Dave, check out this thread.

> > > I'm Exhausted < < <

-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
WA. state, 1 mile south of the Canadian border,
I am not at the end of the world, but you can see it from here.
Have; '66 Monza Coupe - 140, 4-spd. Daily driver beater
'67 Monza Vert. - 140, 4-spd. Daily driver beater
'67 A/C Moredoor Monza
Have had; '61 Monza coupe, 80hp, PG
'62 Monza Wagon, 4spd.
'63 Spyder,
'65 Corsa
.
non-vair
'04 Dodge Cummins Quad Dually, approaching 400K
'03 Honda Del Sol
17'Terry

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