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Hello all - I built this relatively modified turbo BMW. I have an issue controlling boost with this big turbo and my single wastegate placement. I can't fit another in that area so I am going to weld one directly to the turbine housing which is cast iron.The purple thing is the wastegate coming off the collector there. The way the turbo sits I can't place another on the front or sides. The flange looks like this:It is conveniently the same size as 1 1/2" Schedule Pipe.I want to put it on this:The slightly rusty housing is where its going to go. I will probably need a small piece of schedule pipe to place it at the right angle closest to the fender. So I have a choice of 304-L or 316-L schedule pipe.I may not do the welding myself though I have access to a TIG and MIG. I know you have to preheat cast iron but honestly its above my head. What do you guys recommend?
Reply:Found a pic of what I am trying to do:You can see the wastegate attached to the turbine housing. That housing in the picture is cast iron, just brand new.
Reply:Jon, so your idea is to weld the SS flange directly to the CI turbine housing, apparently?Are you aware that any amount of weld/heat distortion, will trash the turbo?(The shaft/sleeve bearings and the blades run at tight clearance tolerances.)Are you aware that the extreme heat cycling which the turbine housing endureswill really tax even the best weld filler, weld joint, weld process?Are you aware of any other successful efforts to do what you're proposing?Blackbird
Reply:Honestly ???? Seriously Honestly ??? It's a turbo and you want to weld to it ?? Being polite here, You will be buying a new turbo when you get done, I think. Aside from being cast. The tolerances in a turbo are so tight that any modification you do other than a bolt on, imho will destroy the turbo. Or at least cause premature failure. I could be and am probably wrong, but I wouldn't weld to a turbo.I once drove to Atlanta Georgia from NJ. While I was down there, my air compressor bracket mounting bolt snapped in the head. Truck had air brakes. I borrowed a welder and a few stainless rods and tacked the bracket to the head. It was 2 yrs later when I went to change the belt that I had to fix it correctly. Welding to cast can be ok, but a turbo ?????Lincoln Ranger 8 Lincoln 175 Drill pressLincoln 225 mig Plasma 8 ft brake 52" jump shear
Reply:I am aware - this should be no issue really - the housings are extremely thick and the unit would be preheated to keep the delta from being so great. Turbos are designed to withstand intense heat - I've seen the housings glowing before (and not evenly). I understand your concern. It seems that the other picture I posted worked out well. I have heard of this before I just don't know enough about welding to do it myself. I constructed my manifold and such, and exhaust, but have never welded cast iron. I want to take it to a shop but I want to understand how best to do it.Why not? People weld exhaust flanges on... when going from a 5 bolt to a v-band flange. People weld the cast aluminum side all the time (mine is welded, I have a wiggins clamp welded on). Welding cast things is fine.. I am not sure why the scared responses.
Reply:Originally Posted by Jon KI am aware - this should be no issue really - the housings are extremely thick and the unit would be preheated to keep the delta from being so great. Turbos are designed to withstand intense heat - I've seen the housings glowing before (and not evenly). I understand your concern. It seems that the other picture I posted worked out well. I have heard of this before I just don't know enough about welding to do it myself. I constructed my manifold and such, and exhaust, but have never welded cast iron. I want to take it to a shop but I want to understand how best to do it.Why not? People weld exhaust flanges on... when going from a 5 bolt to a v-band flange. People weld the cast aluminum side all the time (mine is welded, I have a wiggins clamp welded on). Welding cast things is fine.. I am not sure why the scared responses.
Reply:The party that performed the work in the other picture is some crazy man in Sweden some where. I have no way of tracking him down. This turbo has about 800 miles on it. It looks "rusty" because we all know how iron does in moist climates. I understand its a different process and so on.
Reply:I have no first hand experience with this, but have done a lot of research.Before welding another waste gate into your system, I would try the following:1) Buy a bigger waste gate and put it on the existing location. How big is the one on there now? I would think a single Tial 44mm unit would do fine.or2) Re do the waste gate pipe so that it is larger and angled so that flow does not have to reverse itself.or3) Buy a turbine housing that has an integrated EWG (exhaust waste gate) flange. (I think that's what's in your pic above)Last edited by bucket8577; 09-06-2009 at 06:41 AM.Strictly a hobbiestLincoln AC225Millermatic 130Everlast 200LX...mercy to the guilty is cruelty to the innocent... Adam Smith, The Theory of Moral Sentiments, p. 170.
Reply:Odd, it looks as if the welded turbo in the picture has never run. No heat discoloration of any kind. Makes for a pretty picture though. Show me the same part after 10k miles. As for your welding of the housing, according to the co-worker of mine that was an engineer at IHI, " yeah, quickest way to make turbo yard art" . Find a different way, and you will be much happier.
Reply:If the one in the pics you posted has been proven-meaning you have seen them work. Pull apart turbo cut hole and bevel parts, preheat to 600 degrees or so, tig with 99nickel. Postheat at 600 and cool to 400 in no less than 1hr. Turn off heat and let cool in still air (oven).Peter
Reply:I'm thinkin, if you can afford a modified turbo beamer......you can afford a housing with the wastegate flange cast in like the pic bucket posted.
Reply:I've been talked into welding exhaust turbine housings a couple of times, like everyone else i don't think it's a great idea though. Both times it was a virgin turboOne was letting in a wastegate take off similar to the pic in the second post but for a street and strip hayabusa. Turbo was a Garrett (Ni-resist iron housing), wastegate pipe was 16swg 316L. Welded it cold as i didn't have the means to accurately preheat it at the time (oven doesn't go high enough for CI). Filler was inconel 82 (erNiCr-3), not because i thought it was better than Ni99 or a NiFe, was just the best match to hand (did i say i was talked into it?). Did the welding in short runs (while doing another job) to keep it cool to the touch. That was around 3-4 years ago, doesn't see high milage (not the most tractable of bikes by all accounts and chain/tyre life isn't the best!) but when it is used... it's abusedThe other one was a few months ago to get a mate on the road in time for a hill climb (Nissan 200sx with an rb25 engine transplant). Last minute rush building the car, new turbo arrived and the v band fitting turned out to be some weird non standard size (long boring story, can't remember the details. I just made and welded things while tuning out the jap fanboi speak). Quickest way out was to weld another v band on for the downpipe, inco 82 again and did it cold keeping it cool to the touch throughout. Only had a couple of thousand miles put on it so far so far from probative, don't half go well though!
Reply:I takled to a local welding/fab shop that said they can do this and will "do everything necessary". Of course they're calling it my own risk and such. Hrm. What to do...
Reply:What size is your current waste gate?Is there a reason that you can't go to a bigger size?Controlling boost with two WG's would be more complicated than with one. I'm sure that it can be done. But getting boost dialed with one WG is hard enough. I don't think I'd like to try with two.Strictly a hobbiestLincoln AC225Millermatic 130Everlast 200LX...mercy to the guilty is cruelty to the innocent... Adam Smith, The Theory of Moral Sentiments, p. 170.
Reply:I am currently using a TiAL 44mm. It barely fits where it is. I am debating on installing a second 44 at a not so good location or putting a TiAL 60mm off of the turbo.
Reply:Jon whines:I takled to a local welding/fab shop that said they can do this and will "do everything necessary". Of course they're calling it my own risk and such. Hrm. What to do...1-Expecting any shop to assume liability for damage on a repair that ishighly questionable, just isn't realistic. If you wish to commission a shop, todo an R&D project to create and verify a guaranteed 'perfect' result--thatmight be doable, albeit it would run into some real money. This is what I term a Best Effort Repair--and require customersignoff in advance. If it works, fine--if it doesn't-that's fine, too--thecustomer still pays for the effort (sometimes with a deposit on the front end). You've got other options, as others have mentioned:1-get a made housing with intergral outlet2-I suggest considering using Castweld---if he's willing to do a Best Effort,no guarantee, above any other shop.Blackbird
Reply:Man people are really edgy around here.Casting a custom turbine housing? Wut?Anyway...TiAL sells turbine outlet flanges:http://tialsport.com/prod_fl_to.htmIn fact if you follow this link:http://tialsport.com/NewHotness.htmlAnd scroll down you will seeGT4708/18 Turbine Housing Discharge FlangeOnce Thought to be Extinct.At TiAL, we got tired of not knowing the answer to your simple question: "Where can I find a discharge flange for my GT47 turbo?" We now have the answer: right here! Available in Carbon Steel currently (stainless on a per-order basis) this flange slips down into the housing to create a smooth exit for the exhaust gas and connects with a V-Band clamp.Matching Clamp: VC 525 (aka VC 5153) That makes me think this is not all that insane. I contacted them for their outlook on the matter. If they're selling SS flanges to be welded onto cast iron GT47 housings, I can't see how welding their SS flange onto a Precision PT76 cast iron.I am not trying to put liability on anyone - you can take those remarks back. I want to do this if its possible and if its reliable. I didn't build a 1000 hp car to put liability on a welder .... unbelievable.
Reply:You asked for some recomendations, and got them from some people that should be considered experts in their field. Im sorry but from the perspective of an engineer at an engine company, what you want to do is a cob job for lack of a better term. Its just on one of those things that makes the hair on the back of my neck stand up , and probably a lot of other professionals as well. I would seriously suggest using the correct size WG in the correct location. As for liability, that is a concern of the person doing the work more than the customer. So it IS a concern for the weldor. There is no such thing as " no warranty " work, especially when it becomes fatal. so its something most of take very seriously.
Reply:I wouldn't worry about it warping it. That housing is going to get WAAAAYYYY hotter with egt's from your 1k hp, than the housing will get from welding with it. It welded on a 3.5 V-band on my T70. Like I said (on TM.com), I forget the rod I Ni rod I used, it was the harder of the two my buddy had. But it was a MS flange to the turbine housing. I'm not sure of the SS to the housing with different expansion rates and all. I know the way I did it worked for me without any ill effects. I din't pre-heat as I read post cool down was most important. Threw it in a turbo blanket that kept it hot for a looong time. Maybe you can do a MS stub to the flange, then MS to cast ? Does JGS make a gate bigger that will fit the same flange like they did with the 40mm on the 35-38mm flanges ?
Reply:I wouldn't worry about it warping it. That housing is going to get WAAAAYYYY hotter with egt's from your 1k hp, than the housing will get from welding with it. It welded on a 3.5 V-band on my T70. Like I said (on TM.com), I forget the rod I Ni rod I used, it was the harder of the two my buddy had. But it was a MS flange to the turbine housing. I'm not sure of the SS to the housing with different expansion rates and all. I know the way I did it worked for me without any ill effects. I din't pre-heat as I read post cool down was most important. Threw it in a turbo blanket that kept it hot for a looong time. Maybe you can do a MS stub to the flange, then MS to cast ? Does JGS make a gate bigger that will fit the same flange like they did with the 40mm on the 35-38mm flanges ?http://img215.imageshack.us/img215/8...dedhosuing.jpgSorry guys, can't edit and I know I re-sized. My kung fu just sucks.
Reply:Welded alot of turbos over the years and yet to have any issues at all.Taking the hot side off the turbo before welding it will prevent any damage to the center section.I have always used SS rod with high amps and never had afailure [email protected]://streetorstripconcept.com/index.htmlhttps://www.facebook.com/streetorstripconcepthttp://instagram.com/streetorstripconcept
Reply:In the pic you posted of the modified turbo it looks like the WG is placed in a horrible location.The feasibility of welding this completely aside, from a fluid dynamics standpoint I have to imagine that would wreak havoc on the efficiency of your turbo.The mani with the cast in WG doesn't seem much better to me. I can only imagine the turbulence and who knows what sort of effects to the gas flow and efficiency.I just can't believe it's your best choice. Sorry if you didn't hear everything you wanted to hear on here but I mean really?My turbo is a lot smaller but it's in the motor bay of a MK1 MR2.The mani and turbo are inches from my firewall.I relocated my oil filter, and battery to make it fit the way I wanted. Almost relocated my alt but made it work.I have internal WG which is nice and made my life easier but if I really needed to I could figure out a way to plumb in 4 externals. The turbo in my car is a $150 junk yard dog. I have no problem experimenting with it but if I had big money into a turbo no way I'd play with something like that. And again I'm not even talking about the welding CI aspect but instead the performance aspect and the unknown variables you are introducing.What is the problem you are having? Creep? Spike?I see there are bigger WGs why not start there first? Do you have it vented to atmos or returning to the exhaust I can't tell from the pic?Why couldn't you T off the WG pipe?Lincoln precision TIG 275Millermatic 140 MIG
Reply:Everything else aside...I`m not a turbo engineer so I`m not up on if this is the best fix for this....but as a welder that HAS welded plenty of turbine housings I can tell you they are welded all the time....typically with 309 or 312 ss. Any ss rod with high Ni content will work for this sort of dissimilar stuff such as cast to ss. I would always preheat them on a hot plate. (coleman stove with aluminum plate on burner)
Reply:This is great hearing of people that have had success welding these.I find myself getting deeper and deeper into the world of turbocharged FI and more knowledge always helps.Brian Nye and or Streetorstrip have you guys done much on used turbos?I have read a lot about cast repair and one thing often mentioned is that old manifolds and such can be a PITA because of the extra carbon buildup.Has anyone experienced this to be a serious issue?Lincoln precision TIG 275Millermatic 140 MIG
Reply:Silver solder or brazeing an option?I would not weld on the turbine housing casting .If you do, you should call the manufacturer and ask what the material is.Be safe. If it cast steel and you are welding stainless to it you would use 309L.312 is the old system that needs a buttering pass of 310 first. and all that was replaced with 309 filler.You always need to know what the parent material is FIRST.You want to add a larger waste gate. Why????What does the waste gate do? Think about it.It helps to slow down the turbine and keep it under control.Is your turbo over speeding? You need to find all of these things out and I would start by asking the manufacturer what they recommend.Last edited by Donald Branscom; 12-22-2009 at 09:03 PM.AWS certified welding inspectorAWS certified welder
Reply:Originally Posted by welderman1Silver solder or brazeing an option?
Reply:im with brian... pre heat, then harris 99 rod or a high ni filler and its good to go..Air vantage 500 on the 08' KWharris torchesl25 pro suitcasecomletely restored 1969 SA200 redfaceon my 08' duramaxPIMPN AINT EASY
Reply:I spend a lot of time over at Supraforums and have seen some posts on this. I know that some manufacturers sell the housings with the wastegate flange on them, but according to some of the knowledgable guys over there, they have some turbulence issues with that placement. Are you sure that your boost creep is due to the wastgate piping and not your controller. Try running only on the spring (bypass the controller solenoid) and see if you still get creep. I just went back and read your posts more thoroughly and realized that you are using a pretty big turbo. That 44 wastegate is definitely too small. Straight from the housing may or may not work out well for you. Have you considered installing a second wastegate, maybe off the front of your collector? As far as the welding goes, I have no first hand experience, but I know that vband flanges are welded to turbo outlets as a normal course of business. Good luck, nice car,Rene
Reply:I was thinking about this a bit more today. I am trying to get motivated myself to finish up my Supra that hasn't been driven in a few years. I am going to replace my existing turbo (single). In the end, I am going with a GT3582r .63 hotside. That setup will deliver close to 500 rwhp and have full boost by 3500 rpm. There are a lot of guys running 1k horse Supras and, to be honest, those cars really are not very driveable. That just takes the fun completely out of it for me. If you are drag racing the car, then bigger is almost always is better. If you are driving the car on the street, a gt4088r or PT67dbb may be a whole lot more fun and be real world faster. You can still get over 700 with race gas and a bit more on the bottle. Waiting for 5500 for the turbo to hit and then just having tires go up in smoke till 4th gear just isn't fast, but it is fun. I know that this isn't the question you asked, but I just like talking cars and am taking a different approach with mine than you are with yours. In any event, good look with the car.Rene
Reply:Originally Posted by yoshimitsuspeedThis is great hearing of people that have had success welding these.I find myself getting deeper and deeper into the world of turbocharged FI and more knowledge always helps.Brian Nye and or Streetorstrip have you guys done much on used turbos?I have read a lot about cast repair and one thing often mentioned is that old manifolds and such can be a PITA because of the extra carbon buildup.Has anyone experienced this to be a serious issue?
Reply:Originally Posted by yoshimitsuspeedThis is great hearing of people that have had success welding these.I find myself getting deeper and deeper into the world of turbocharged FI and more knowledge always helps.Brian Nye and or Streetorstrip have you guys done much on used turbos?I have read a lot about cast repair and one thing often mentioned is that old manifolds and such can be a PITA because of the extra carbon buildup.Has anyone experienced this to be a serious issue?
Reply:Awsome thanks for the info guys.I will be playin around with a couple old cracked housings I have.Lincoln precision TIG 275Millermatic 140 MIG
Reply:You probably don't need a bigger wastegate. The design of your header is wrong. Your wastegate needs to be able to flow smoothly off the uppipe. You have it set like a T. It needs to flow more like a Y. Your exhaust is just flowing over it instead of in to itJust my $.02 as a turbo salesman who designed 2000hp drag cars......What's your backpressure to boost ratio? Is that a 38mm WG? What kind of turbo combo are you running?
Reply:As far as if running the wastegate how he wants to I personaly wouldnt run a set up like that Im just say from the welding side it is possible.I dont know if he is going to get the best results [email protected]://streetorstripconcept.com/index.htmlhttps://www.facebook.com/streetorstripconcepthttp://instagram.com/streetorstripconcept
Reply:Originally Posted by jmtebbensYou probably don't need a bigger wastegate. The design of your header is wrong. Your wastegate needs to be able to flow smoothly off the uppipe. You have it set like a T. It needs to flow more like a Y. Your exhaust is just flowing over it instead of in to itJust my $.02 as a turbo salesman who designed 2000hp drag cars......What's your backpressure to boost ratio? Is that a 38mm WG? What kind of turbo combo are you running?
Reply:Originally Posted by 874crawlerLooks like a tial v44. 44mm wastegate.Having it setup like a Y will help but the way it is it should still work. The exhaust will take the path of least resistance, but I agree you may just be able to reposition your wastegate
Reply:I know this thread has been hijacked (sorry). But if that is a Tial 44, Precision Turbo has a 46mm WG that uses the same flanges. Something to think about before you go cutting up your turbine housing.
Reply:Originally Posted by StreetorstripConceptI have welded on used turbo's and used manifolds before.It doesn't make anything any easier but is possible.If they have been used already I sand blast as much as i can get to wire wheel,grind,etc etc.Pretty much whatever I can do to get the material back to a new clean state.
Reply:Something else I noticed that may hurt his power is the amount of welding involved in the pipes for the exhaust, if there are any protrusions from the beads into the flow of exhaust gasses that will cause turbulence as well I would think as the gas enters the turbo so wouldn't that be an issue?
Reply:Originally Posted by Big65moparSomething else I noticed that may hurt his power is the amount of welding involved in the pipes for the exhaust, if there are any protrusions from the beads into the flow of exhaust gasses that will cause turbulence as well I would think as the gas enters the turbo so wouldn't that be an issue? |
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发表于 2021-9-1 00:39:37