cheapest wastegate
05-05-04, 04:37 PM
#3
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Back from the dead! Does anybody have experience with the 'generic' hks wastegates sold on ebay?
eBay item 2476817670 (Ends May-08-04 19:00:00 PDT) - 50mm HKS Greddy style wastegate - FREE SHIPPING
I called the shop selling them and they said they're made by a company called XS Power. Apparently, they've put them on a bunch of cars and haven't had any problems.
I know the wastegate is a critical part so I'm reluctant to take the chance, but I can't bring myself to completely rule it out based on the fact that the 50mm version costs about 2/3rds what the 40mm tial goes for (note, I'm assuming they're both measured the same way).
eBay item 2476817670 (Ends May-08-04 19:00:00 PDT) - 50mm HKS Greddy style wastegate - FREE SHIPPING
I called the shop selling them and they said they're made by a company called XS Power. Apparently, they've put them on a bunch of cars and haven't had any problems.
I know the wastegate is a critical part so I'm reluctant to take the chance, but I can't bring myself to completely rule it out based on the fact that the 50mm version costs about 2/3rds what the 40mm tial goes for (note, I'm assuming they're both measured the same way).
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05-05-04, 11:13 PM
#8
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Originally posted by RETed
If you can't afford a proper WG, be ready to risk blowing your engine.
-Ted
If you can't afford a proper WG, be ready to risk blowing your engine.
-Ted
05-06-04, 12:40 AM
#9
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in most cases knock offs arent worse than the product they are being knocked off of.. however they are not proven like the product they are copying. With something like a wastegate i am inclined to spend teh extra$$ to be sure it wont fail only because a wastegate failure is probably the worst thing that could happen.
I will try to find a used "name brand" one myself for around 250
I will try to find a used "name brand" one myself for around 250
05-06-04, 12:43 AM
#10
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I heard of wastegates going bad by getting sticky. Instead of opening gradually, it pops open, closes, pops open, closes........... So then you get a nice rev limiter type bouncing in your exhaust. I don't know what kind of wg it was or if it's even a true story, but who would make something up like that
05-06-04, 01:07 AM
#11
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Originally posted by CCarlisi
Well, I guess that is my question-is it a 'proper WG.' Really a wastegate is nothing but a spring operated valve. Someone on this forum that had access to a machine shop created one from scratch last year as a weekend project. Is it really necessary to pay $550-750 for something so simple? I'd feel more comfortable saying yes to that question if someone could point out some specific flaws with the $250 knock off.
Well, I guess that is my question-is it a 'proper WG.' Really a wastegate is nothing but a spring operated valve. Someone on this forum that had access to a machine shop created one from scratch last year as a weekend project. Is it really necessary to pay $550-750 for something so simple? I'd feel more comfortable saying yes to that question if someone could point out some specific flaws with the $250 knock off.
It's just a simple pneumatic valve.
If you were going to copy a design, at least copy the Tial one!
"Cheap" is crap like Turbonetics, which seize and reward you with runaway boost that kills your engine...instantly.
If the machining it top-notch, I have no problem getting a "knock-off", minus all the moral arguments.
The problem is, the machining is probably not as good and you risk having an inferior product that could cause engine failure.
Too loose of a tolerance risks the piston valve to eat itself or **** sideways and seize itself at a bad moment.
Too tight of a tolerance, and you have a non-function valve.
Bad, loose, or poor quality diaphram will risk the diaphram blowing out, and you end up with runawway boost - again, engine failure.
I just don't understand how people will pay thousands of dollars for a rebuild or replacement engine, and then try and save a few hundred dollars by skimping on the wastegate.
I find next to the ECU (i.e. stand-alone EMS), the wastegate is probably the next most important thing to preventing engine failure. A crappy turbo just leaves with low boost or spewing oil, neither of which will usually cause an engine failure - and people are willing to spend hundreds more on a turbo than a wastegate...
Sorry, I'm not singling you, but it's just a general rant of mine...
Performance is not cheap.
If you can't afford to pay to play, don't waste your money.
-Ted
05-06-04, 08:05 AM
#12
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If the diaphram blew out i dont think that would be a big issue, you would just revert to spring pressure... the biggest thing you have to worry about is the valve sticking shut.
05-06-04, 11:49 AM
#13
No it's not Turbo'd
I'd rather pay for something to have been "Lab" Tested, than, "hey it worked for that Supra over there ! (Question How many runs has he made with that !?) (Answer: Two) 
05-06-04, 01:26 PM
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I'd like to throw some fuel on the fire:
Maybe I'm wrong...but it seems like most folks with single turbos are using them as a street toy or drag racing car.
Who has done extensive testing on wastegates using a true torture test: road racing/track events? I have heard over the years that folks can "get away" with some of these units on the street/strip and when they take their cars to track events and <cough> drive them hard </cough> that the wastegates like to stick and tend to blow motors.
In particular, I know of the Apexi RX6 and GReddy T-78 being susceptible to this problem.
Anyone who is more than a "casual" track event participant care to shed some light on this?
I've heard that a genuine Tial is the wastegate du jour for this application...
Maybe I'm wrong...but it seems like most folks with single turbos are using them as a street toy or drag racing car.
Who has done extensive testing on wastegates using a true torture test: road racing/track events? I have heard over the years that folks can "get away" with some of these units on the street/strip and when they take their cars to track events and <cough> drive them hard </cough> that the wastegates like to stick and tend to blow motors.
In particular, I know of the Apexi RX6 and GReddy T-78 being susceptible to this problem.
Anyone who is more than a "casual" track event participant care to shed some light on this?
I've heard that a genuine Tial is the wastegate du jour for this application...
05-06-04, 02:08 PM
#15
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Originally posted by XSTransAm
If the diaphram blew out i dont think that would be a big issue, you would just revert to spring pressure... the biggest thing you have to worry about is the valve sticking shut.
If the diaphram blew out i dont think that would be a big issue, you would just revert to spring pressure... the biggest thing you have to worry about is the valve sticking shut.
This means overboost...
-Ted
05-06-04, 02:50 PM
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Originally posted by bond007
I'd like to throw some fuel on the fire:
Maybe I'm wrong...but it seems like most folks with single turbos are using them as a street toy or drag racing car.
Who has done extensive testing on wastegates using a true torture test: road racing/track events? I have heard over the years that folks can "get away" with some of these units on the street/strip and when they take their cars to track events and <cough> drive them hard </cough> that the wastegates like to stick and tend to blow motors.
In particular, I know of the Apexi RX6 and GReddy T-78 being susceptible to this problem.
Anyone who is more than a "casual" track event participant care to shed some light on this?
I've heard that a genuine Tial is the wastegate du jour for this application...
I'd like to throw some fuel on the fire:
Maybe I'm wrong...but it seems like most folks with single turbos are using them as a street toy or drag racing car.
Who has done extensive testing on wastegates using a true torture test: road racing/track events? I have heard over the years that folks can "get away" with some of these units on the street/strip and when they take their cars to track events and <cough> drive them hard </cough> that the wastegates like to stick and tend to blow motors.
In particular, I know of the Apexi RX6 and GReddy T-78 being susceptible to this problem.
Anyone who is more than a "casual" track event participant care to shed some light on this?
I've heard that a genuine Tial is the wastegate du jour for this application...
-The Tial 38mm flows as good or better than the 40mm. Apparently this is because the 38mm uses a different design than the 40.
-Assuming a 38mm can control boost, no horsepower will be gained by going with a larger wastegate; the turbo is the only thing that significantly effects backpressure on the motor.
-Aside from increased capacity, the 46mm sheds heat and maintains the valve tolerances better than the 38mm wg due to the design of the cooling fins and the material it is constructed from. For this reason, they usually recomend the 46mm to people that do a lot of track events (road not drag). However, the 38mm will hold up fine if it receives good airflow and isn't too close to the exhaust manifold.
-The diaphrams are the weak link. The diphrams can sustain temps of 500-550 for a long time, and 600-650 short term (he didn't give any specific time limits)
-The design and material of the metal parts effects not only the tolerances for the valve, but also how much heat the diaphram sees and for how long.
-Many of the HKS and Greddy wastegates use cast construction, which sheds heat much slower than the stainless steel machined(?) construction used by Tial.
05-06-04, 02:53 PM
#17
Senior Member
Originally posted by XSTransAm
If the diaphram blew out i dont think that would be a big issue, you would just revert to spring pressure... the biggest thing you have to worry about is the valve sticking shut.
If the diaphram blew out i dont think that would be a big issue, you would just revert to spring pressure... the biggest thing you have to worry about is the valve sticking shut.
05-06-04, 03:41 PM
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Originally posted by CCarlisi
-The diaphrams are the weak link. The diphrams can sustain temps of 500-550 for a long time, and 600-650 short term (he didn't give any specific time limits)
-The diaphrams are the weak link. The diphrams can sustain temps of 500-550 for a long time, and 600-650 short term (he didn't give any specific time limits)
So, to increase reliability of a primarily track-driven single turbo RX-7, one would need to "optimize" WG placement or increase your service checkup interval on the diaphragm (or use an internal wastegate which has its own set of issues).
How much are diaphragms in general?
The critical parameter to observe is the temperature that the diaphragm is exposed to, which sounds like a temperature datalogging experiment (albeit a complicated one) to try on several manifold designs with the same wastegate.
Any volunteers?
--Ashraf (not quite convinced to run a single...yet...)
05-06-04, 04:34 PM
#20
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So that being said, what would be optimal placement for a wastegate? (single turbo / single wastegate application)
I'd imagine too far away and your boost control wouldn't be as accurate.
I'd imagine too far away and your boost control wouldn't be as accurate.
05-06-04, 10:20 PM
#22
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Originally posted by 82streetracer
What about jacketing the wastegate and cooling it with engine coolant.
I believe the apexi piece is like this.
should be simple to set up and should greatly increase longevity.
What about jacketing the wastegate and cooling it with engine coolant.
I believe the apexi piece is like this.
should be simple to set up and should greatly increase longevity.
If anyone figures this out, drop us some hints!
-Ted
05-06-04, 10:26 PM
#23
No it's not Turbo'd
Wow something else, that's really hot increasing my coolant temps ! Great ! Where do I sign up !?
I think it's a cool idea, but personally if you go to the track every weekend, a 46mm wastegate and proper placement, so that the fins grab some cool air from under the car shouldn't be a big deal.
If you do a couple of track events a year, have the wastegate checked once in a while just for your own peace of mind... same as you would with brakes, and treadwear... belts etc... Racing a Car is tough on the components, that's why most show cars aren't race cars...
I think it's a cool idea, but personally if you go to the track every weekend, a 46mm wastegate and proper placement, so that the fins grab some cool air from under the car shouldn't be a big deal.
If you do a couple of track events a year, have the wastegate checked once in a while just for your own peace of mind... same as you would with brakes, and treadwear... belts etc... Racing a Car is tough on the components, that's why most show cars aren't race cars...
05-08-04, 08:10 PM
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bond007, I think that's a good idea.
I'm still hoping someone will chime in with more details on optimal wastegate placement. Obviously too close and the heat will damage the wastegate (re: diaphram sticking), would too far away cause erratic boost control? slow response?
You can mount it lower, to help promote cooling from air under the car, and as you suggested I don't see a reason why a simple sheet metal scoop underneath wouldn't help direct air in it's direction.
I'm still hoping someone will chime in with more details on optimal wastegate placement. Obviously too close and the heat will damage the wastegate (re: diaphram sticking), would too far away cause erratic boost control? slow response?
You can mount it lower, to help promote cooling from air under the car, and as you suggested I don't see a reason why a simple sheet metal scoop underneath wouldn't help direct air in it's direction.