Slant Six Forum
https://www.slantsix.org/forum/

removing the exhaust heat riser set up
https://www.slantsix.org/forum/viewtopic.php?t=10501		 Page 3 of 4
Author:  Dennis Weaver [ Fri Oct 01, 2004 7:42 am ]
Post subject: 
You're right. I surrender, I can't stand it anymore... ;)

Converting all my stuff to heated intake, don't know what I was thinking. :roll:

D/W
Author:  stinky mctinkerpants [ Fri Oct 01, 2004 10:09 am ]
Post subject: 
i agree with you frank on gettting cold air in the carb and warming it in the manifold for evaporating any condensed fuel. my questioning of the heat riser is in one position it focuses the exhaust heat at the intake manifold and when warm directs it out the exhaust, if you removed the flapper would'nt it do both all the time with a less restricted flow? i am still not sure if i am for or against this mechanism, it really seems to depend on the level of performance you are trying to achieve. I personally am going for good gas milage with enough performance to give the v8's a surprise. everybodys need is different and it sounds like the people for keeping the valve are minimal work stock daily drivers and those for removing it are like me and know there is always an improvement to make. it all goes back to if you are going to change something do it informed. it seems like everyone here is happy with thier own personal decision on this and done it. in the end i am going to show my wife how it works, have her read the posts and let her make the call, its her car and she has uncanny good sense about these things.
Author:  Dennis Weaver [ Fri Oct 01, 2004 11:32 am ]
Post subject: 
Note: wiring it in the "cold" position can be reversed in 2.0268 seconds... :idea:

D/W
Author:  FrankRaso [ Fri Oct 01, 2004 12:48 pm ]
Post subject: 
Stinky, I can tell that you really don't like this device. Now that you have everything apart, just try doing this one thing. Do like Dennis says and wire it into the hot position. Look in the bottom of the exhaust manifold where you connect the exhaust pipe. See for yourself if the flapper valve seems to be in the way of the exhaust gases. Now imagine that the valve were gone. Which way would the exhaust gases have smoother exit?

Whenever you put an elbow or a change in flow are into a pipe, you put in a restriction. I did a quick search on google for piping equivalent lengths and came up with the following links that might help you better understand what I mean:

http://www.cheresources.com/eqlength.shtml (a bit dry)

http://aquanic.org/publicat/usda_rac/efs/srac/373fs.pdf (comprehensive)

They discuss water systems but the theory is exactly the same for gases. Don't bother reading the entire articles unless you're getting ready for bed. Just scan through them and look to see that the losses I mentioned are in there.

If you really want better performance from your exhaust, you'll get a much bigger improvement with a larger diameter exhaust pipe.

Frank
Author:  Dennis Weaver [ Fri Oct 01, 2004 1:03 pm ]
Post subject: 
Quote:
Whenever you put an elbow or a change in flow are into a pipe, you put in a restriction.
I have wholeheartedly agreed with this point going back to the beginning of the thread. Frank, you and I at least seem to both concur that taking out the valve offers no advantage on a /6. That's why I suggest wiring it cold. This is less of a flow disturbance, and if one doesn't like the results, its very easily reversible.

D/W
Author:  stinky mctinkerpants [ Fri Oct 01, 2004 2:12 pm ]
Post subject: 
i definitly agree wiring it one way or another is a no harm way to modify. as far as plumbing, frank i really think you are comparing apples and oranges. my point is based on planned obsoletion, what any manufacturer knows is that if you make a perfect product it will be your last. this valve, when cold, focuses a strong amount of heat and pressure right on to an other wise weak gasket area with an egr valve run by a rubber diaphram. One problem car companies have had with emissions is warm up. temperature controlls are always squirrely. anyone who has ever worked on any home or commercial heating equiptment can tell you that. since the dawn of pollution concerns the big three american auto concerns have fought and whined, most pollution control systems are poorly built, and use more gas. this whole system stinks of last minute engineering to keep the liberals happy, its just out of the scope of the traditional do-it-yourselfer maintenence of the time. i still cannot say as to weather or not this piece is at all important but i do know a car company wants to sell cars, and parts and in america GAS. This is not the first junky little add on i have seen that creates big problems when it fails and requires serious repairs. I mean seriously only mopar makes the lube, the piece cannot be replaced (at least easily), and it siezes easily. whats all that about then, somebody explain to me why this thing is built like crap.
and craig come on, give me a little credit, i put the torch to the manifold, and it was only a propane torch. should i draw you a picture.
Author:  Dennis Weaver [ Fri Oct 01, 2004 2:41 pm ]
Post subject: 
Do I smell a government conspiracy??? 8) :shock: :roll:

Seriously, this is a driveability device not a smog control device... The automakers started using these things long before government mandated pollution laws.

D/W
Author:  stinky mctinkerpants [ Fri Oct 01, 2004 9:58 pm ]
Post subject: 
i think i am going to wire it a little less than half way open then drill two 1/8" holes in it at equal axis. :D
Author:  FrankRaso [ Sat Oct 02, 2004 10:44 am ]
Post subject:  Give it a try and let us know how it works
When you make a modification hoping to achieve some sort of gain, it helps to know if you succeeded. Measure something that's important to you (highway fuel consumption, 1/4" mile time, etc) before you make the change and measure it again after the change. I'm not sure why you want to fix the valve partly open but I am interested in the results.

BTW, when you think I'm comparing apples and oranges by showing you water flow information when we are discussing exhaust flow, it's only because there is more information available about water flow. The principles of fluid dynamics apply to liquids and gases, the difference between the two is that you also have to consider the compressibility of gases. It's a complex subject but I was just trying to show that there really are losses at changes in direction and flow area.

Frank
Author:  stinky mctinkerpants [ Sat Oct 02, 2004 11:23 am ]
Post subject: 
frank, i was kidding, i'll probably end up wiring it open. And comparing water to gas is silly, you must be a plumber. unfortunatly i really have no way to compare since i am going from some jacked up mickey mouse single barrel setup that someone had peiced together so bad i am converting to a super six.
Author:  Dennis Weaver [ Sat Oct 02, 2004 12:20 pm ]
Post subject: 
Quote:
frank...you must be a plumber...
Ruh-roh! :shock:

stinkymctp, you haven't gotten the subtle hint by now that Frank is an ENGINEER??! :lol: :lol: :lol:

D/W

P. S. - I think plumbers make more than us in the engineering field... ;)
Author:  stinky mctinkerpants [ Sat Oct 02, 2004 5:47 pm ]
Post subject: 
now that explains everything, and i was starting to really listen to you guys :D
now i am taking the torch to the whole car, wearing a blindfold, when i am done it will be the best car ever, a motorcycle
:twisted:
just kidding, its been fun debating this.
I could smell engineer when the idea of an uncharted modification sturred so much hubub. thats okay though, i still think your cool.
Author:  kesteb [ Sun Oct 03, 2004 5:22 pm ]
Post subject: 
Engineers design, technicans fix the design...
Author:  Dennis Weaver [ Sun Oct 03, 2004 8:17 pm ]
Post subject: 
True.
Author:  Flyntgr [ Wed Oct 06, 2004 7:52 pm ]
Post subject:  exhaust leak at heat riser butterfly
My passenger side butterfly shaft leaks almost like a bad exhaust gasket, so what can I do to seal off the butterfly shaft so it won't sputter exhaust? I've thought of brassening it in the open position, but apparently that wouldn't be a good idea. It leaks at the outside end of the shaft, so is there anything like JB weld or something which I could apply to seal it off-that would last a long time? Thanks.
Page 3 of 4 All times are UTC-08:00
Powered by phpBB® Forum Software © phpBB Limited
https://www.phpbb.com/