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

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.

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

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

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

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

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

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?

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

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

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

<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?

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

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

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

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

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

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.

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

<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!!