exhaust stubs, thinking of cutting a heat exchanger |
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exhaust stubs, thinking of cutting a heat exchanger |
worn |
Jul 28 2014, 01:46 PM
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#1
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can't remember Group: Members Posts: 3,164 Joined: 3-June 11 From: Madison, WI Member No.: 13,152 Region Association: Upper MidWest |
Can any one out there comment on the idea of cutting off the 6 inches or so of the heat exchanger where it meets the heads and adding flanges there so that the exhaust can be dropped without disturbing the head joint?
I have a spare set of heads so I ws thinking of mounting the heat exchangers, slicing and then tack welding the flanges while still in place. I was thinking of using V flanges with rings as well so you could still get to the head studs with a socket. Ideas? (IMG:style_emoticons/default/popcorn[1].gif) |
McMark |
Jul 28 2014, 02:05 PM
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#2
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914 Freak! Group: Retired Admin Posts: 20,179 Joined: 13-March 03 From: Grand Rapids, MI Member No.: 419 Region Association: None |
It'll work as well as you can weld and fabricate. (IMG:style_emoticons/default/wink.gif)
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stugray |
Jul 28 2014, 02:07 PM
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#3
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Advanced Member Group: Members Posts: 3,825 Joined: 17-September 09 From: Longmont, CO Member No.: 10,819 Region Association: None |
With the massive PITA of removing these exhausts and the risk associated with messing up the studs, I have thought about this myself.
I am even keeping a nasty old set of HEs just for this purpose |
worn |
Jul 28 2014, 05:13 PM
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#4
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can't remember Group: Members Posts: 3,164 Joined: 3-June 11 From: Madison, WI Member No.: 13,152 Region Association: Upper MidWest |
Yeah. Well I tend to agree with that one. (IMG:style_emoticons/default/agree.gif) Given that I pull it off - is it a reasonable idea? I find that I want to pull the exhausts to do things like check the valves, replace an alternator and track down pesky oil leaks. Now that I am backdating to 1974, I am not gonna have the two into one sink p trap to disconnect anymore. Thank goodness! |
ChrisFoley |
Jul 28 2014, 07:05 PM
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#5
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I am Tangerine Racing Group: Members Posts: 7,934 Joined: 29-January 03 From: Bolton, CT Member No.: 209 Region Association: None |
The port end of SSIs is rather flimsy.
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worn |
Jul 28 2014, 07:54 PM
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#6
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can't remember Group: Members Posts: 3,164 Joined: 3-June 11 From: Madison, WI Member No.: 13,152 Region Association: Upper MidWest |
The port end of SSIs is rather flimsy. Meaning they wouldn't make strong stubs? What if I used the port ends of stock 1976? I appreciate that you are following this Chris. Trying to put together a six and keep the 4 running at the same time has required bargain hunting. And of course I like experimenting too. Haven't the er thingies to drive as fast as you do though. (IMG:style_emoticons/default/unsure.gif) |
ChrisFoley |
Jul 29 2014, 08:04 AM
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#7
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I am Tangerine Racing Group: Members Posts: 7,934 Joined: 29-January 03 From: Bolton, CT Member No.: 209 Region Association: None |
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worn |
Jul 29 2014, 08:38 AM
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#8
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can't remember Group: Members Posts: 3,164 Joined: 3-June 11 From: Madison, WI Member No.: 13,152 Region Association: Upper MidWest |
The port end of SSIs is rather flimsy. Meaning they wouldn't make strong stubs? Exactly. QUOTE What if I used the port ends of stock 1976? I guess, if you can make them fit up to the HE pipes. Would it help to tie the two stups together with a cross brace? Assuming room which I am not so sure of. |
rick 918-S |
Jul 29 2014, 08:54 AM
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#9
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Hey nice rack! -Celette Group: Members Posts: 20,493 Joined: 30-December 02 From: Now in Superior WI Member No.: 43 Region Association: Northstar Region |
The port end of SSIs is rather flimsy. Meaning they wouldn't make strong stubs? Exactly. QUOTE What if I used the port ends of stock 1976? I guess, if you can make them fit up to the HE pipes. Would it help to tie the two stups together with a cross brace? Assuming room which I am not so sure of. Expansion and contraction may be dissimilar from the heads. By locking the two together it may cause a leak. It's a puzzle with lots of trial and error to get it right. |
rhodyguy |
Jul 29 2014, 08:55 AM
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#10
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Chimp Sanctuary NW. Check it out. Group: Members Posts: 22,092 Joined: 2-March 03 From: Orion's Bell. The BELL! Member No.: 378 Region Association: Galt's Gulch |
i think if you take 6" off of the head ends of the heat exchangers you'll be into the bottom curve of the pipes. you're going with stainless?
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worn |
Jul 29 2014, 10:08 AM
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#11
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can't remember Group: Members Posts: 3,164 Joined: 3-June 11 From: Madison, WI Member No.: 13,152 Region Association: Upper MidWest |
i think if you take 6" off of the head ends of the heat exchangers you'll be into the bottom curve of the pipes. you're going with stainless? Yeah, I would say that is correct. I have experience welding stainless, and thought it worked well. I might fill the tubes with argon. The welds will be to flanges, not directly joining tubes. The curve is a problem. One solution would be to cut the stock stubs off at the point they start to curve and join to a straight point on the new stainless. That way, the HEs would drop down and that might magnify the problem. I ordered the flanges, but I have a lot of things I never used... |
lonewolfe |
Jul 29 2014, 01:17 PM
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#12
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Senior Member Group: Members Posts: 819 Joined: 12-September 11 From: Oakland, CA Member No.: 13,549 Region Association: Northern California |
I've thought about doing this to my car as well. It would be cool to be able to run heat exchangers in the winter and then headers during the warmer months. I was thinking of using stubs from a European Racing header. Those damn studs break too easily when removing the exhaust. Is there a type of exhaust stud that is not so fragile that could be put into the heads?
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rhodyguy |
Jul 29 2014, 07:03 PM
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#13
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Chimp Sanctuary NW. Check it out. Group: Members Posts: 22,092 Joined: 2-March 03 From: Orion's Bell. The BELL! Member No.: 378 Region Association: Galt's Gulch |
Remember that the j- tubes, branch ducting, warm air elbows will all be dropping too. You'll have make it all work and connect to the fan shroud. Heat control wire too.
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worn |
Jul 30 2014, 07:36 AM
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#14
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can't remember Group: Members Posts: 3,164 Joined: 3-June 11 From: Madison, WI Member No.: 13,152 Region Association: Upper MidWest |
Remember that the j- tubes, branch ducting, warm air elbows will all be dropping too. You'll have make it all work and connect to the fan shroud. Heat control wire too. Yeah, we kinda ruled that out last night drawing on a paper bag. My son asked: is this common? It seems convenient. My comment was I had seen it in some of the higher quality headers. Never seen an add on to HEs though. Odd. I am always the last one to know etc.... |
worn |
Aug 3 2014, 08:54 PM
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#15
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can't remember Group: Members Posts: 3,164 Joined: 3-June 11 From: Madison, WI Member No.: 13,152 Region Association: Upper MidWest |
The port end of SSIs is rather flimsy. I measured a set of ss heat exchangers, vendor fuzzy. I got a wall thickness of 0.080 The stock came out as 0.125 That would very strongly substantiate what Chris said. The whole point is to leave the joint at the head unmolested while pulling the exhaust. Query: is this really worth a stub joint and flange effort? Query 2: Why do we see stubs on the better headers if not for this reason? I have discovered I can make it work with ss HEs. Do I want to? |
7TPorsh |
Aug 4 2014, 12:32 PM
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#16
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7T Porsh Group: Members Posts: 2,691 Joined: 27-March 06 From: Glendale Ca Member No.: 5,782 Region Association: Southern California |
Don't the later models already have a two into one setup like this?
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SKL1 |
Aug 4 2014, 12:55 PM
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#17
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Senior Member Group: Members Posts: 1,605 Joined: 19-February 11 From: north Scottsdale Member No.: 12,732 Region Association: Upper MidWest |
Didn't someone make aftermarket headers and exhaust sytem that did just that? I remember looking into that system a couple years ago, but apparently the guy who made the system died and the idea must have died with him...
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worn |
Aug 5 2014, 07:09 PM
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#18
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can't remember Group: Members Posts: 3,164 Joined: 3-June 11 From: Madison, WI Member No.: 13,152 Region Association: Upper MidWest |
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