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73-87 Chevy _ GMC Trucks => 4 Wheel Drives => Topic started by: 86Silverado64 on April 25, 2012, 12:22:02 pm

Title: Air injected manifold swap for headers
Post by: 86Silverado64 on April 25, 2012, 12:22:02 pm
honestly yall I have searched the site for the answer to my question, I'm sure someone else has asked the same thing, but I cant find my exact question.  I have a 1986 Chevy K10 that came originally with a 305 sbc but now has a 350 GMcrate engine.  I want to put headers on it but the stock ehaust manifolds have the air tubes running into them.  Can I remove all that emissions clutter to 'clean up' the engine compartment or do I have to buy the headers that have the air inlets?  Im in NC so I dont have to have emissions, except for catalytic converter.  The exhaust on now are true duals coming off from the stock manifold and running indepently out the back.  Any suggestions on what I can do and recommendation on headers would be greatly appreciated.  I would love to put the shortys on because i could diconnect the regular manifolds and bole the  shortys right up to existing connection, but they are a little to pricey for me.  I'm hoping to get a set for between 150 to 200 dollar range regular headers).  Once again though I'm not sure about the air line going into the original manifolds.  Any help would be great, thanks.  Oh I have ac and an automatic tranny/
Title: Re: Air injected manifold swap for headers
Post by: 1979C20 on April 25, 2012, 12:38:45 pm
If you don't need it for emissions, then don't worry about it. Just pull the charcoal canisters, egr, smog pump, and manifolds off. Put your headers on, remove all vacuum lines except for the vac advance, brake booster, heater, and tranny modulator. The same thing I did with my truck.
Title: Re: Air injected manifold swap for headers
Post by: 86Silverado64 on April 25, 2012, 03:36:17 pm
thanks for the quick reply.....have a good day!

Title: Re: Air injected manifold swap for headers
Post by: thirsty on April 25, 2012, 05:18:06 pm
When you remove the charcoal canister were do you vent your fuel tank to? Vented cap and plug the line?
Title: Re: Air injected manifold swap for headers
Post by: Donut on April 25, 2012, 09:11:05 pm
On my C-30, (I know it's the 4wd  section, shoot me!) I pulled the smog pumps and manifolds and kept the charcoal canister.  Personally I'd rather not have the fumes from the tank all summer.  My '73, no charcoal canister...
Title: Re: Air injected manifold swap for headers
Post by: bake74 on April 26, 2012, 07:06:45 am
     I agree, leaving the charcoal canister to vent the fumes from the gas tank is smart and your nose will thank you.  If you don't need it, pull the rest off.  May I make a suggestion though, if you have room keep everything you pull off in case you or someone else in the future may need it.
Title: Re: Air injected manifold swap for headers
Post by: 1979C20 on April 27, 2012, 03:15:53 pm
I re-routed my gas tank vent. I put a breather cap on the end of the hose and tiead it to a bed support above the rear axle. I smell no fumes ever, even outside my truck.
Title: Re: Air injected manifold swap for headers
Post by: frotosride on April 27, 2012, 08:14:03 pm
I just did the same thing recently. I haven't removed all the smog equipment and i kept the OE manifolds as well as left all the air injection tubing in place foe now. If you haven't found headers in your budget try these.
http://www.summitracing.com/parts/BIG-49152FLT
  They bolted up realy easy and there were only two simple problem areas to over some but nothing unusual from full length headers. A/C brackett... you have to clearance it to fit around the tube for number one cyl. 2nd starter wiering... highly reccomend getting a sleeve to insulate them as well as re routing them closer to the block. The best thing is that despite the 3" collector there is no interfierance with the shackel hangers for the front leaf springs because they extend a few inches beyound that point.
 I just completeda 900 mile move (west ten-east va) on these towing roughly 600-700lbs in the bed and other than the shotty "Y" pipe that the muffler shop did there were no problems with the headers.
Title: Re: Air injected manifold swap for headers
Post by: 86Silverado64 on April 30, 2012, 06:10:45 pm
Well after a call, to the shop I do business with, I am gonna have to have the air injected headers after all.  Wanted to clean  the engine compartment up a little but I guess this isnt gonna be an option due to inspections.  Thanks for the help yall!
Title: Re: Air injected manifold swap for headers
Post by: frotosride on May 01, 2012, 10:03:39 am
That doesn't mean you have to leave the extra grunt hiding in those stock manifolds. just save a lil more and get smog style headers.
Title: Re: Air injected manifold swap for headers
Post by: 86Silverado64 on May 04, 2012, 04:30:34 pm
thanks for the replies.........may patent a 'quick connect smog out of the hat' trick.....lol.  Still deciding.....yall have a good one.