cheapest wastegate
05-09-04, 12:58 AM
#26
I am just a casual track participant, but I did have the A'PEXi wastegate get stuck. Fortunately, it would get stuck open on the track (really bad low end, but as long as you are up in the revs it doesn't matter that much). It got stuck shut on the street after a long freeway drive home from the track and overboosted like a ****. It wasn't a bad diaphragm, but rather I think the valve would just get stuck when it got really hot.
From my limited research of popular wastegates, HKS and TiAL seem to have the best reputations from a reliability standpoint. The HKS SS Racing wastegate is almost a perfect replacement (bolts right up to manifold, slight ovaling of the holes needed for dump tube) for the A'PEXi one, too, so that is what I have been running for the last 1-2 years.
The reliability of a particular wastegate should not be applied to knock-offs of that wastegate. Just because a knock-off looks like a certain wastegate or is even constructed similarly, that doesn't mean it will perform the same. It is a combination of the basic design and the small details that determine reliability. If the valve guide clearance is 0.002" too small and it causes the valve to stick, you can't see that by looking at a picture on ebay. It would be nice to have more reliable, low-priced wastegate alternatives, but I don't want to experiment with my engine that costs many times as much as even the costliest wastegates. And really, the TiAL wastegates are absolutely top-notch and are rather affordable. Get a TiAL.
A pop-off valve should be a useful defense against a bad wastegate (or perhaps more likely, some problem with the hoses). If the wastegate goes bad, you will know it immediately. But it might be immediately after you pop your motor at 35 psi.
-Max
From my limited research of popular wastegates, HKS and TiAL seem to have the best reputations from a reliability standpoint. The HKS SS Racing wastegate is almost a perfect replacement (bolts right up to manifold, slight ovaling of the holes needed for dump tube) for the A'PEXi one, too, so that is what I have been running for the last 1-2 years.
The reliability of a particular wastegate should not be applied to knock-offs of that wastegate. Just because a knock-off looks like a certain wastegate or is even constructed similarly, that doesn't mean it will perform the same. It is a combination of the basic design and the small details that determine reliability. If the valve guide clearance is 0.002" too small and it causes the valve to stick, you can't see that by looking at a picture on ebay. It would be nice to have more reliable, low-priced wastegate alternatives, but I don't want to experiment with my engine that costs many times as much as even the costliest wastegates. And really, the TiAL wastegates are absolutely top-notch and are rather affordable. Get a TiAL.
A pop-off valve should be a useful defense against a bad wastegate (or perhaps more likely, some problem with the hoses). If the wastegate goes bad, you will know it immediately. But it might be immediately after you pop your motor at 35 psi.
-Max
05-09-04, 09:57 PM
#27
Old [Sch|F]ool
Brainstorm:
You never hear about wastegate diaphragm failure with internal wastegates, do you? The diaphragm/spring/can assembly is remotely mounted.
So how about a remotely-mounted can on an external wastegate?
I think I need to get to work...
You never hear about wastegate diaphragm failure with internal wastegates, do you? The diaphragm/spring/can assembly is remotely mounted.
So how about a remotely-mounted can on an external wastegate?
I think I need to get to work...
05-09-04, 10:35 PM
#28
Moderator
iTrader: (3)
Join Date: Mar 2001
Location: https://www2.mazda.com/en/100th/
Posts: 30,849
Received 2,613 Likes
on
1,852 Posts
Originally posted by peejay
Brainstorm:
You never hear about wastegate diaphragm failure with internal wastegates, do you? The diaphragm/spring/can assembly is remotely mounted.
So how about a remotely-mounted can on an external wastegate?
I think I need to get to work...
Brainstorm:
You never hear about wastegate diaphragm failure with internal wastegates, do you? The diaphragm/spring/can assembly is remotely mounted.
So how about a remotely-mounted can on an external wastegate?
I think I need to get to work...
05-10-04, 12:39 PM
#29
No it's not Turbo'd
Pop Off = Best defense against Boost Creep, Boost Controller Failure, and Wastegate Failure... Basically if you are afraid of overboosting your motor, get one, if you're not afraid, and have modded your motor, start getting afraid... 
05-21-04, 03:33 PM
#31
Senior Member
Join Date: Jul 2003
Location: Edmonton, AB, Canada
Posts: 408
Likes: 0
Received 0 Likes
on
0 Posts
The HKS Racing Blow off valve can act as an pop off valve as well. You just hook up the lower nipple to a boost source. Whenever the boost gets too high it bleeds it out.
-Trent
-Trent
05-21-04, 03:42 PM
#32
No it's not Turbo'd
I think that's the Greddy BOV you're thinking of... Hks is the SSQ, and has one nipple Edit: Well maybe the racing one, I haven't needed to vent 30+ psi
Greddy Makes a Pop off valve, that you adjust the screw on it, just like a BOV, to get it to pop open just like a bov, but unlike a bov, it pops at too much boost. It's kind of like a pressure relief valve on a water heater.. you don't need another hose, it's spring activated...
Edit: Well maybe the racing one, I haven't needed to vent 30+ psi Greddy Makes a Pop off valve, that you adjust the screw on it, just like a BOV, to get it to pop open just like a bov, but unlike a bov, it pops at too much boost. It's kind of like a pressure relief valve on a water heater.. you don't need another hose, it's spring activated...
Last edited by DCrosby; 05-21-04 at 04:00 PM.
05-21-04, 06:16 PM
#33
Ee / Cpe
Join Date: Jan 2003
Location: Gaithersburg, MD / WVU
Posts: 2,843
Likes: 0
Received 2 Likes
on
2 Posts
Originally posted by surfpac
Wrong, it would be a huge issue if the diaphram blew out. The spring holds down the diaphram, which is tied to valve, so if diaphram is ruptured there is no pressure to push open valve.
Wrong, it would be a huge issue if the diaphram blew out. The spring holds down the diaphram, which is tied to valve, so if diaphram is ruptured there is no pressure to push open valve.
HAHAH i just reread my post, I must have been high on crack when i wrote that... sorry guys sometimes i confuse myself
side question, is the tial flange the same as the hks one? im getting a hks cast manifold and want to use a tial valve if possible. (i can get them cheap)
05-22-04, 11:34 AM
#37
Post quality not quantity
Join Date: Feb 2001
Location: Durham, NC
Posts: 521
Likes: 0
Received 0 Likes
on
0 Posts
Originally posted by peejay
So how about a remotely-mounted can on an external wastegate?
So how about a remotely-mounted can on an external wastegate?
http://www.turboneticsinc.com/wastegates.html
The "Newgen" which costs approximately $550 at one online dealer that I saw...
So we go from the tried and not so true (because of a specific known failure) diaphragm type to something that has been tested in OEM turbo applications but not as an external device...
Who is going to bite the bullet in the wallet and try one of these?
05-22-04, 05:17 PM
#38
Rotary Enthusiast
Join Date: Aug 2001
Location: Waiting for Indykid to catch up
Posts: 1,236
Likes: 0
Received 1 Like
on
1 Post
I am curious as to why more people dont fuel cut on the PFC as overboosting protection. It works great for me. I have it set up to come on 2-3 lbs over my max boost.
05-24-04, 11:35 AM
#39
No it's not Turbo'd
Because, fuel cut causes a lean condition in the combustion chamber, and can detonate...
Fuel and Sparc cut, is the best idea, since then all you have is air, and no sparc to light whatever is left on fire ......
Re: Wastegate Discussion
I'm uncertain as to whether he's talking about a new wastegate @ 38mm or whether that was implied, or whether he couldn't talk about it yet...
Fuel and Sparc cut, is the best idea, since then all you have is air, and no sparc to light whatever is left on fire ......
Re: Wastegate Discussion
I spoke to the president of Tial today. He made a couple points I want to share with everyone.
-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.
-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.
Last edited by DCrosby; 05-24-04 at 11:44 AM.
05-24-04, 12:23 PM
#40
Post quality not quantity
Join Date: Feb 2001
Location: Durham, NC
Posts: 521
Likes: 0
Received 0 Likes
on
0 Posts
Originally posted by DCrosby
I'm uncertain as to whether he's talking about a new wastegate @ 38mm or whether that was implied, or whether he couldn't talk about it yet...
I'm uncertain as to whether he's talking about a new wastegate @ 38mm or whether that was implied, or whether he couldn't talk about it yet...
http://www.tialsport.com/wastegates.htm
Here is how I read what CCarlisi posted:
The 40 and 46 are similar design, but different size passages. The 38 is different from the 40/46 but the smaller passage flows equally to the 40.
They also have a placemarker for a 44mm that isn't released yet.
05-25-04, 11:48 AM
#44
No it's not Turbo'd
Originally posted by bond007
They have three models, 38, 40, and 46:
http://www.tialsport.com/wastegates.htm
Here is how I read what CCarlisi posted:
The 40 and 46 are similar design, but different size passages. The 38 is different from the 40/46 but the smaller passage flows equally to the 40.
They also have a placemarker for a 44mm that isn't released yet.
They have three models, 38, 40, and 46:
http://www.tialsport.com/wastegates.htm
Here is how I read what CCarlisi posted:
The 40 and 46 are similar design, but different size passages. The 38 is different from the 40/46 but the smaller passage flows equally to the 40.
They also have a placemarker for a 44mm that isn't released yet.
don't know... but we'll see
05-25-04, 01:50 PM
#45
Rotary Enthusiast
Join Date: Aug 2001
Location: Waiting for Indykid to catch up
Posts: 1,236
Likes: 0
Received 1 Like
on
1 Post
Originally posted by DCrosby
Because, fuel cut causes a lean condition in the combustion chamber, and can detonate...
Fuel and Sparc cut, is the best idea, since then all you have is air, and no sparc to light whatever is left on fire ......
Because, fuel cut causes a lean condition in the combustion chamber, and can detonate...
Fuel and Sparc cut, is the best idea, since then all you have is air, and no sparc to light whatever is left on fire ......
05-27-04, 11:33 PM
#46
Full Member
Join Date: Nov 2003
Location: new york
Posts: 71
Likes: 0
Received 0 Likes
on
0 Posts
i was just wondering how much room do you have around the wastegate? im triing to go single and after this thread im debating to stay single(vaccum lines suck)
anyway i was just wondering if there was a small amount of room what about a small fan set behind or to the side of the wastegate to blow the hot air off. i have no idea about this stuff im triing to learn it before i make my decison. but any kind of air movement would greatly decrease the heat. just my two cents
anyway i was just wondering if there was a small amount of room what about a small fan set behind or to the side of the wastegate to blow the hot air off. i have no idea about this stuff im triing to learn it before i make my decison. but any kind of air movement would greatly decrease the heat. just my two cents
05-28-04, 11:48 AM
#47
Post quality not quantity
Join Date: Feb 2001
Location: Durham, NC
Posts: 521
Likes: 0
Received 0 Likes
on
0 Posts
Originally posted by bludskorge
i was just wondering how much room do you have around the wastegate? im triing to go single and after this thread im debating to stay single(vaccum lines suck)
anyway i was just wondering if there was a small amount of room what about a small fan set behind or to the side of the wastegate to blow the hot air off. i have no idea about this stuff im triing to learn it before i make my decison. but any kind of air movement would greatly decrease the heat. just my two cents
i was just wondering how much room do you have around the wastegate? im triing to go single and after this thread im debating to stay single(vaccum lines suck)
anyway i was just wondering if there was a small amount of room what about a small fan set behind or to the side of the wastegate to blow the hot air off. i have no idea about this stuff im triing to learn it before i make my decison. but any kind of air movement would greatly decrease the heat. just my two cents
05-28-04, 01:29 PM
#48
No it's not Turbo'd
I'd say ducting, since you're not boosting to the point where the wastegate opens much in stop and go traffic And Air flow from the speeds you're going at when the wastegate comes into play is where ducting would work best...
And Air flow from the speeds you're going at when the wastegate comes into play is where ducting would work best...
05-28-04, 01:39 PM
#49
No it's not Turbo'd
Originally posted by radkins
From what I understand fuel cut is a total cut of fuel and not partial, therefore only air is in the combuston chamber so no chance of detonation. I have hit fuel cut dozens of times over the past few years and never had any issue. I have heard the "theory" that it is bad, but I have never heard of anyone blowing and engine by hitting fuel cut. The rev limiter on the PFC as I understand it cuts fuel and I hit that offen as well. Also, Racelogic traction control cuts fuel and I know a few people who run this on there FD with no issues. I agree that spark cut AND fuel cut would be ideal, but anything is better than your boost ramping up to 25lbs on a pump gas map huh?
From what I understand fuel cut is a total cut of fuel and not partial, therefore only air is in the combuston chamber so no chance of detonation. I have hit fuel cut dozens of times over the past few years and never had any issue. I have heard the "theory" that it is bad, but I have never heard of anyone blowing and engine by hitting fuel cut. The rev limiter on the PFC as I understand it cuts fuel and I hit that offen as well. Also, Racelogic traction control cuts fuel and I know a few people who run this on there FD with no issues. I agree that spark cut AND fuel cut would be ideal, but anything is better than your boost ramping up to 25lbs on a pump gas map huh?
The truth lies more in between these two extremes... fuel clings to the metal sides when injected, and not all of it burns away during combustion.
Therfore the danger of fuel cut, with the plug still fireing... as well as that "Pure" Oxygen is combustable without fuel...
If the Plug is no longer fireing, the fact that you're compressing hot air (depending on IC), and making it even hotter, can cause the fuel to ignite by-itself.. (detonation)
I'm just not sure that the question of sparc or fuel cut is as clear cut as some people make it seem.
05-28-04, 11:10 PM
#50
Rotary Enthusiast
Join Date: Nov 2003
Location: Canada
Posts: 814
Likes: 0
Received 0 Likes
on
0 Posts
Originally posted by radkins
From what I understand fuel cut is a total cut of fuel and not partial, therefore only air is in the combuston chamber so no chance of detonation.... I have hit fuel cut dozens of times over the past few years and never had any issue. I have heard the "theory" that it is bad, but I have never heard of anyone blowing and engine by hitting fuel cut. The rev limiter on the PFC as I understand it cuts fuel and I hit that offen as well. Also, Racelogic traction control cuts fuel and I know a few people who run this on there FD with no issues. I agree that spark cut AND fuel cut would be ideal, but anything is better than your boost ramping up to 25lbs on a pump gas map huh?
From what I understand fuel cut is a total cut of fuel and not partial, therefore only air is in the combuston chamber so no chance of detonation.... I have hit fuel cut dozens of times over the past few years and never had any issue. I have heard the "theory" that it is bad, but I have never heard of anyone blowing and engine by hitting fuel cut. The rev limiter on the PFC as I understand it cuts fuel and I hit that offen as well. Also, Racelogic traction control cuts fuel and I know a few people who run this on there FD with no issues. I agree that spark cut AND fuel cut would be ideal, but anything is better than your boost ramping up to 25lbs on a pump gas map huh?