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| | | Forums66 Topics128,196 Posts1,057,395 Members48,471 | | Most Online14,466 Apr 26th, 2026 | | AD Chevy Trucks Over 6,000 pictures Brad Allen has an awesome collection of Chevrolet factory pictures that he has set up from film strips. Check them out!
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on the Internet for over 30 years! and not clogged down with Ads! Again, thanks! | | | | Joined: Apr 2013 Posts: 67 Shop Shark | | Shop Shark Joined: Apr 2013 Posts: 67 | So, anybody got a clue why Chevy put 6 brass bolts on the carb side of the 230????
Ill try to post photo. They are at the same level as the coolant temp sending unit. They arent holding anything.
Very Curious. | | | | | Joined: May 2005 Posts: 1,624 Shop Shark | | Shop Shark Joined: May 2005 Posts: 1,624 | I just looked through my photos of close ups of the carb and intake/exhaust area and saw no brass bolts. Can you zero in on it a bit? On one of my other old cars I did I use silicon bronze bolts on the exhaust flanges as they don't rust.
Last edited by beltfed; 07/06/2016 11:59 AM.
Six volt guy living in a twelve volt world
| | | | | Joined: Feb 2001 Posts: 1,094 'Bolter | | 'Bolter Joined: Feb 2001 Posts: 1,094 | May be a later model head with some emission ports blocked with brass plugs.
Tommy 59 apache 1/2t 261 short stepside | | | | | Joined: Dec 2001 Posts: 14,522 Moderator: Welcome Centre, Southern Bolters, Legion Hall | | Moderator: Welcome Centre, Southern Bolters, Legion Hall Joined: Dec 2001 Posts: 14,522 | Some grade 8 bolts look like brass???? Got a picture? | | | | | Joined: May 2005 Posts: 1,624 Shop Shark | | Shop Shark Joined: May 2005 Posts: 1,624 | I think Tommy is on to it. I didn't think of it but several years ago I owned a mid 70's 250. It had six brass plugs inserted into holes that I was told were for a air reactors, which was some sort of belt driven pump. I believe it was to force air into the exhaust to help with emissions.
Six volt guy living in a twelve volt world
| | | | | Joined: Feb 2004 Posts: 29,886 Kettle Custodian (pot stirrer) | | Kettle Custodian (pot stirrer) Joined: Feb 2004 Posts: 29,886 | Those holes go into the exhaust ports and were for the "Air Injection Reactor" tubing. Air was pressurized by a belt-driven pump and injected into the exhaust stream to assist the catalytic converter in cleaning up the exhaust gases. It was a routine thing to rethread the holes to 1/4" pipe thread and put brass pipe plugs into the ports when removing the A.I.R system. Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt! There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway Love your enemies and drive 'em nuts!
| | | | | Joined: Jan 2015 Posts: 914 'Bolter | | 'Bolter Joined: Jan 2015 Posts: 914 | A I R Pipes. I replaced a few of those pipes. | | | | | Joined: Sep 2011 Posts: 1,462 'Bolter | | 'Bolter Joined: Sep 2011 Posts: 1,462 | If it's A.I.R.(air injection reaction) we know it's not a '63 head!
BC 1960 Chevy C10 driver 261 T5 4.10 dana 44 power loc 1949 GMC 250 project in waiting 1960 C60 pasture art Retired GM dealer tech. 1980 - 2022 | | | | | Joined: Apr 2013 Posts: 67 Shop Shark | | Shop Shark Joined: Apr 2013 Posts: 67 | Thanks everyone. I think I have the answer. However, not sure if this is a '63 motor now. | | | | | Joined: Apr 2013 Posts: 67 Shop Shark | | Shop Shark Joined: Apr 2013 Posts: 67 | What year does that make this? How do you know this info? | | | | | Joined: Feb 2001 Posts: 1,094 'Bolter | | 'Bolter Joined: Feb 2001 Posts: 1,094 | There are numbers cast into the side of the block above the starter behind the distributor. these will tell you what it is. post them and someone will tell you what you have.
Tommy 59 apache 1/2t 261 short stepside | | |
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