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05-08-2012, 07:13 PM
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#1 |
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Registered User
Join Date: Sep 2009
Location: westbank bc
Posts: 239
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What is this?
 i86.photobucket.com/albums/k104/d-2-da-m/20120508_160443.jpg[/IMG] What is this And what dose it do? It's on a 76 with a 350 small block straight piped Posted via Mobile Device |
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05-08-2012, 07:13 PM
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#2 |
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Registered User
Join Date: Sep 2009
Location: westbank bc
Posts: 239
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Re: What is this?
 Posted via Mobile Device |
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05-08-2012, 07:36 PM
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#3 |
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Getting Old; Going Broke
Join Date: Apr 2010
Location: Owasso OK
Posts: 2,764
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Re: What is this?
Was part of the emissions that were removed.
__________________
Why is every used 350 sbc out of a corvette? There's only two things that excite a man, expensive toys and real expensive toys. VEGETARIAN: That's an old Indian word meaning "I don't hunt so good." When the going gets tough, switch to power tools. |
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05-08-2012, 07:44 PM
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#4 |
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Registered User
Join Date: Sep 2009
Location: westbank bc
Posts: 239
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Re: What is this?
Should it be flipped any certain way? It's flipped up right now, dose that effect anything? What dose it do inside the pipe?
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05-08-2012, 08:11 PM
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#5 |
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Registered User
Join Date: Mar 2009
Location: gravois mills missouri
Posts: 47
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Re: What is this?
Its the heat riser. It has a butterfly inside that when cold channels warm air through a flexable pipe to the air cleaner. The heat shield has a hole in the top you can see that the pipe would have attached too.
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1963 chevy shortstep 327 1965 c60 292 2007 Ram 3500 5.9 cummins |
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05-08-2012, 08:39 PM
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#6 |
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Getting Old; Going Broke
Join Date: Apr 2010
Location: Owasso OK
Posts: 2,764
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Re: What is this?
Had a K5 that had it on there. I took the exhaust loose and removed the piece and blew the butterfly out with a torch and then put the piece back on. They sell a replacement section at the auto parts stores but the blow torch method was free.
__________________
Why is every used 350 sbc out of a corvette? There's only two things that excite a man, expensive toys and real expensive toys. VEGETARIAN: That's an old Indian word meaning "I don't hunt so good." When the going gets tough, switch to power tools. |
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05-08-2012, 09:51 PM
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#7 |
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78K & 79C Jimmys
Join Date: Nov 2009
Location: Ottawa Ont CANADA
Posts: 7,901
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Re: What is this?
here is a close pic
mine fell off the 79 after i took the bolts out lol I've seen holes drilled/filled to see if it was open or closed before,poke a coat hanger up,holding open tacked from outside
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John 1978 GMCJimmy4X4-350/203 1979 GMCJimmy4X2-305/350 |
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05-09-2012, 08:51 AM
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#8 |
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Registered User
Join Date: Nov 2004
Location: Long Island NY
Posts: 293
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Re: What is this?
I have the same thing, I removed the valve and thingamabobber that tied into the vacuum line with the carb and bypassed it. I assumed it was part of the A.I.R. (smog) system on my 454. I plan on pulling it all the way out when I do new exhaust. I was thinking it had something to do with the choke as well since it was tied into the carb... I get a kick out of early emissions attempts..
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I feel sorry for people who don't drink....because when they wake up in the morning, that's the best they're gonna feel all day long!---Frank Sinatra RIP [B]1972 Chevrolet K5 Blazer RIP 1986 GMC Sierra K3500 1TON, Long Box, V8350 RIP 1980 Chevy Silverado C30 Cab and Chassis, 454 TH400HD. RIP [B] 1995 Chevrolet Tahoe 2D [B] |
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05-09-2012, 06:47 PM
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#9 |
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Registered User
Join Date: Jun 2000
Location: Wichita Falls,Tx
Posts: 56
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Re: What is this?
That is the heat riser. yours was operated with a vacuum diaphragm. Some earlier ones had a bimetallic spring. Anyway this heat riser when closed forced the exhaust up thru a port in the middle of the exhaust manifold and then thru a passage under the intake manifold exiting thru the other exhaust manifold.
When this is operating right is not a bad thing to have. It helps the motor to warm up faster which helps mileage, emissions and the heater. The sheet metal part riveted to the middle of the exhaust manifold is the heat stove. When the engine is cold, warm air from around the exhaust manifold is pulled into carb to help with fuel vaporization . Not a bad thing to have either. It helps with cold weather drivable and emissions. When motor is warm this isn't used. |
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05-10-2012, 01:57 AM
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#10 |
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Registered User
Join Date: Sep 2009
Location: westbank bc
Posts: 239
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Re: What is this?
It's a summer truck, never seen snow and No plans too so would it be smart to take out?
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05-10-2012, 07:45 AM
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#11 |
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Getting Old; Going Broke
Join Date: Apr 2010
Location: Owasso OK
Posts: 2,764
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Re: What is this?
Since the only thing left is the butterfly piece, there is no sense in leaving it in there. Now if you are wanting to spend a few $100 and buy all the junky emission pieces that have already been removed from your truck and try to make the valve work again, then leave it.
It is probably not hurting anything, but it has zero function right now.
__________________
Why is every used 350 sbc out of a corvette? There's only two things that excite a man, expensive toys and real expensive toys. VEGETARIAN: That's an old Indian word meaning "I don't hunt so good." When the going gets tough, switch to power tools. |
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05-10-2012, 08:44 AM
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#12 |
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78K & 79C Jimmys
Join Date: Nov 2009
Location: Ottawa Ont CANADA
Posts: 7,901
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Re: What is this?
for a summer truck you won't miss it
around here most seem to rust and sieze up,in a bad way, closed looks a little cleaner I think too
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John 1978 GMCJimmy4X4-350/203 1979 GMCJimmy4X2-305/350 Last edited by motornut; 05-10-2012 at 08:55 AM. |
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05-19-2012, 03:24 PM
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#13 |
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Registered User
Join Date: Apr 2009
Location: Steelville mo
Posts: 52
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Re: What is this?
I'm dealing with the same part. Mine is all still intact except i removed the vacuum line. Is it now stuck open or does it need to be wired open?
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05-19-2012, 05:43 PM
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#14 |
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425hp409
 
Join Date: Oct 2008
Location: Prosper Texas
Posts: 841
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Re: What is this?
As Philiip Pennarz stated correctly, this is a "Heat Riser Valve". As it is the open position at this time from the photo you posted, there would be no real value in removing it. If it were to stay in the closed position you would have an exhaust restriction for the right bank. Unless it is rusted stuck, it can be moved by the lever on it. If it is in the closed position and you cannot move it, it would be a good thing to take the exhaust loose and remove wither the flapper valve, or to replace the assembly with a "Dummy Valve" available from the parts store.
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Charles 68 SWB, Dad bought new, now 396 & factory ac 64 Impala SS, 409 425HP, 4 speed AC 64 Bel Air Wagon, 400 Small Block 57 Bel Air all original 283 w/Factory Air 77 GMC Sprint, 454/425HP 67 Olds 442, all original 90 ZR1 Corvette |
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05-19-2012, 07:14 PM
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#15 |
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Registered User
Join Date: May 2012
Location: Visalia CA
Posts: 118
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Re: What is this?
Another simplistic 70s idea
Lol but really smog requires it to b installed, it was used to heat the engine faster to reduce emmissions upon first startup. Take an oxy torch to the mechanism if u wanna keep the look without the restriction. But beware here n cali all smog must be retained, hwy patrol can pop ur hood and fine u if alls not there so keep in mind! Posted via Mobile Device |
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