Smog system, should i run it or de-gut and plug??

[XXXGoldL34M20]

I was wondering what you guys have done with your smog system on your Big Block Chevy's.
My friend has a 1969 Z-28 and he told me to de-gut the smog pump and plug the holes with roofing nails under the tubes on the manifold for better performance which he did to his own car.
I am currently putting together the entire Smog system for my LS6 454 and just wanted your opinions if i should just run it normally or de-gut and plug.

[Postsedan]

I have done bought, based on customer decisions. If I owned your LS6, I would make it as true and original as I could. If you have the entire original smog ready to go....I say put it back on the car as the Chevrolet did!

Dan

[m22mike]

I agree with Dan, your not really gaining much in performance by gutting it anyway. JMO. And as you may know, under heavy throttle the pump is dumping overbaord.

Mike

[XXXGoldL34M20]

Here is a pre assembly photo of the work i did this morning.
Just wanted to make sure everything fit right.
Will wait till motor gets back to do a final installation, meanwhile more opinions neaded if i should run it like stock or de-gut and plug.
I went through Google to see what i can read up on this subject and really not much luck on finding threads about de-gutting and plugging the smog,but i did find threads about how the system works and it really only robs about 1 or 2 horsepower and ads weight.
Also it was pointed out that the smog pump can sieze up and make the belt break apart at some point.
Has anyone here have that problem?

[olredalert]

----Dont use the exhaust manifold gaskets. GM didnt!......Bill S

[XXXGoldL34M20]

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: olredalert</div><div class="ubbcode-body">----Dont use the exhaust manifold gaskets. GM didnt!......Bill S </div></div>
Install them metal to metal? or with a little silicone?

[Postsedan]

I ONLY use Permatex &quot;Ultra Grey&quot; High Torque-High Temp. RTV Silicone. Plus I make sure my exhaust manifolds are straight &quot;True&quot;.....if needed, I take them to my machinist, where he mills a bit off for straightness.

You do not need much of the Silicone, stay close to the inside edge....as you do not want evidence of the silicone as you torque the manifolds.

Dan

[olredalert]

----The Post-man has spoken!!!......Bill S

[SS427]

At least 90% of the cars I restore have non working smog pumps on them. It has nothing to do with robbing horsepower but has everything to do with heat and moisture in the asperator tubes which will discolor and rust them out. On some cars I machine non smog manifolds to accept the asperator tubes but do not drill them completely through so there is no need to plug them.

[Alss]

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Postsedan</div><div class="ubbcode-body">I ONLY use Permatex &quot;Ultra Grey&quot; High Torque-High Temp. RTV Silicone. Plus I make sure my exhaust manifolds are straight &quot;True&quot;.....if needed, I take them to my machinist, where he mills a bit off for straightness.

You do not need much of the Silicone, stay close to the inside edge....as you do not want evidence of the silicone as you torque the manifolds.

Dan </div></div>

I like the ultra copper permatex...its orange!!

[Donnie]

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: SS427</div><div class="ubbcode-body">At least 90% of the cars I restore have non working smog pumps on them. It has nothing to do with robbing horsepower but has everything to do with heat and moisture in the asperator tubes which will discolor and rust them out. On some cars I machine non smog manifolds to accept the asperator tubes but do not drill them completely through so there is no need to plug them. </div></div>

I was basically going to say the same thing as Rick has this morning, but I got side tracked with outside work.

[XXXGoldL34M20]

Thank you guys for your opinions on the smog pump and tips on the silicone.

Now how do i go about taking the guts out of the smog pump?
I remember finding a link to some web site years ago on how to do it but have since lost it or can not find it on google.
Anyone have photo illustrations or a link they can dig up.
Before i do anything i would really like to read up on it or view photos before i attempt this work as it is my first time taking this smog pump apart. <<GRAEMLIN_URL>>/biggthumpup.gif

[XXXGoldL34M20]

Just found it on Team Camaro,
Thanks Pacecar Jeff

http://www.camaros.net/forums/showthread.php?t=175771

http://www.camaros.net/forums/showthread.php?t=165379

[XXXGoldL34M20]

Tonight i gutted out the smog pump.
Followed the directions in the link and all went well.
There were 2 wings with 2 gears on each wing.
Two veins on each side that looks like magnet sticks and one shim on each side.
See photo of what came out.

To plug the manifold holes i will be using the factory extension tubes and cut them shorter and placing a stainless steel roofing nail on the top to plug the hole.
My buddy did it this way for his 69 Z28 so i copied him.
Tomorrow i will finish it all up and ad some high heat silicone to the top of the nail for a great seal <<GRAEMLIN_URL>>/biggthumpup.gif
More photos to come.

[XXXGoldL34M20]

All done !!

I cut the factory smog tubes an inch which was the same size as the stainless steel roofing nail and added just a little high heat silicone on the top of the tube for a great seal between the top of the tube and under the nail head.
The pressure of the bolts that were screwed on have them in there real snug with no play at all.

I had no ball bearing kicking around so i used a metal shelf peg to plug the vacuum line which fit just perfectly with a little help of some lubricant.

Smog pump is now Gutted out, Exhaust Manifold Smog Holes are plugged and Vacuum line is closed. <<GRAEMLIN_URL>>/biggthumpup.gif
Thanks for all the help guys.

[Donnie]

and no one will ever know unless you tell them.

[Postsedan]

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Donnie</div><div class="ubbcode-body">and no one will ever know unless you tell them. </div></div>

Donnie,

Remind me to never buy a car from you <<GRAEMLIN_URL>>/no.gif

Dan

[Mr. Chevy]

Good move with modifying the smog system... It makes for less headaches especially by gutting the pump and most of all if your going to actually drive the car... The roof nail idea is clever.. A friend of mine machines little metal plugs that fall into the smog holes on the manifold and are machined with the exact bevel as the bottom of the smog hole so the plug seats right down into the hole then you screw the tube onto the manifolds...

JMO of course...

Rich

[x Baldwin Motion]

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: XXXBlackLs6M22</div><div class="ubbcode-body">........... robs about 1 or 2 horsepower and ads weight......
</div></div>


http://sphotos.xx.fbcdn.net/hphotos-ash4/4622_1150073240088_1475314340_30401403_7577782_n.j pg&gt;&gt;&gt;DUMPSTER <<GRAEMLIN_URL>>/headbang.gif

[Nova Jed]

Hmm? Where did that come from Chris?

[x Baldwin Motion]

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Nova Jed</div><div class="ubbcode-body">Hmm? Where did that come from Chris? </div></div>

LOL It was a mid 80's van that had a new 350 4 bolt motor, all the accessories were ditched. (no vintage parts)