S5 Wastegate Porting Concern.
03-13-13, 04:33 PM
#1
Freshly Built Streetport
Thread Starter
Join Date: May 2010
Location: Minneapolis, Minnesota
Posts: 206
Likes: 0
Received 0 Likes
on
0 Posts
S5 Wastegate Porting Concern.
So I picked up a S5 turbo in great shape for my S4 TII. Since I'm waiting for warmer weather to install my turbo, I figured why not port it since it was out. I have ported wastegates before. A couple of summers ago I ported my stock S4 wastegate which helped the boost creep issues I had been having. It was not a super aggressive port, but it helped keep the boost levels in check.
So just like with my S4 wastegate porting, I followed the write-up here:
FC3S Pro v2.0:  Main How-To Section
When I did my S5 wastegate, it was again more conservative than what the write-up showed. I enlarged the smaller opening to be pretty close in size to the bigger one, and I didn't even get close to the edges of the flapper for the port. I know the S5's flow pretty well and the flapper wiggles around a bit when it's moving, so no need to go for broke and port to the edge of the flapper.
Here's my issue. After I had cleaned up the port and smoothed everything over, I tested how well it closes a number of times. The flapper sat flush with the port with plenty of flapper clearance over the ports. But when I attached the wastegate arm to the flapper lever, it pulled it shut in such a way that it's now ever so slightly off from level over the smaller hole. Basically, since it's under pressure from only one side, it lifted the opposite corner up just a little bit. High enough that I can push a piece of credit card in there and it'll hold it. I'd take a picture, but it's not really going to help.
I know this will bleed some boost even when closed now. But will it cause slower spooling issues for me? I'm aware that I could just bolt it on as is and it'll work. And for all I know I'm just being paranoid and it won't cause any noticable issues regarding unwanted boost bleed. Just figured I'd ask since I've never heard of this one happening before. Thanks for the help.
So just like with my S4 wastegate porting, I followed the write-up here:
FC3S Pro v2.0:  Main How-To Section
When I did my S5 wastegate, it was again more conservative than what the write-up showed. I enlarged the smaller opening to be pretty close in size to the bigger one, and I didn't even get close to the edges of the flapper for the port. I know the S5's flow pretty well and the flapper wiggles around a bit when it's moving, so no need to go for broke and port to the edge of the flapper.
Here's my issue. After I had cleaned up the port and smoothed everything over, I tested how well it closes a number of times. The flapper sat flush with the port with plenty of flapper clearance over the ports. But when I attached the wastegate arm to the flapper lever, it pulled it shut in such a way that it's now ever so slightly off from level over the smaller hole. Basically, since it's under pressure from only one side, it lifted the opposite corner up just a little bit. High enough that I can push a piece of credit card in there and it'll hold it. I'd take a picture, but it's not really going to help.
I know this will bleed some boost even when closed now. But will it cause slower spooling issues for me? I'm aware that I could just bolt it on as is and it'll work. And for all I know I'm just being paranoid and it won't cause any noticable issues regarding unwanted boost bleed. Just figured I'd ask since I've never heard of this one happening before. Thanks for the help.
03-14-13, 10:27 AM
#4
im sure it would effect spool a tad. perhaps you can bend the end of the wg arm slightly so that it closes better?
if it was me id just install it see how it does... I don't think it will effect spool drasticly or anything... if you have full exhaust, an intake, and or port work it will spool quite fast anyway
if it was me id just install it see how it does... I don't think it will effect spool drasticly or anything... if you have full exhaust, an intake, and or port work it will spool quite fast anyway
Trending Topics
03-14-13, 01:12 PM
#8
and this is one reason i don't consider the S5 turbo to be "superior" as so many people seem to think it is. worn wastegate bushings are pretty common to the S5 turbo and hurt its performance.
it can be repaired but the process is somewhat extensive, requires marking and cutting the arm off, drilling out the old bushing and finding a suitable replacement to modify and press in then welding the arm back on.
it can be repaired but the process is somewhat extensive, requires marking and cutting the arm off, drilling out the old bushing and finding a suitable replacement to modify and press in then welding the arm back on.
Last edited by RotaryEvolution; 03-14-13 at 01:15 PM.
03-14-13, 02:30 PM
#9
Freshly Built Streetport
Thread Starter
Join Date: May 2010
Location: Minneapolis, Minnesota
Posts: 206
Likes: 0
Received 0 Likes
on
0 Posts
Thanks for all the comments guys. I looked at it again last night and I think I may have an option for improvement. Since you have to bend the flapper arm a little to open the flapper all the way for porting, I think the arm didn't bend back to exactly the same spot when I put it back together. It has a slight angle/twist to it that I know with a vise grip I can bend back to a better angle. That may be causing it. Maybe not. We'll see. I do have a front mount, DP, racing beat pre silencer, and HKS silent high power single exhaust. So I have pretty good air flow. I'll take a look at it here soon and I'll let you know what happens.
03-15-13, 06:01 PM
#11
Freshly Built Streetport
Thread Starter
Join Date: May 2010
Location: Minneapolis, Minnesota
Posts: 206
Likes: 0
Received 0 Likes
on
0 Posts
^^^When I test closed mine it fit flush just about any way I tried. And I'd say I limited my porting somewhat as well. The issue I'm having isn't a result of porting out or making the hole wider. It's a combination of possibly porting down a little bit and how the wastegate arm torque's the flapper shut. When I ported out to enlarge the hole, the edges weren't super clean. So I slightly rounded the edges to soften the transition from open to close. I didn't port it down really, just rounded the edge.
I've talked to someone with an S4 engine with S5 turbo running about stock boost, maybe 10 psi, and he said he doesn't have any issues with boost creep. So you may not have to port yours if you plan on lower boost levels. I think I'll end up around 10-12psi and since I had it sitting on my work bench, I decided to port this one too just to be safe.
And I ported both my S4 and S5 turbos without taking them apart. I know this isn't the preferred way, but I wedged paper shop towels down the runners and covered the rear of the turbo wheel. I vacuumed out the shavings every couple of minutes and indirectly used compressed air to blow them out as well. I have thousands of miles on my S4 turbo with no ill affects. Just be careful.
I've talked to someone with an S4 engine with S5 turbo running about stock boost, maybe 10 psi, and he said he doesn't have any issues with boost creep. So you may not have to port yours if you plan on lower boost levels. I think I'll end up around 10-12psi and since I had it sitting on my work bench, I decided to port this one too just to be safe.
And I ported both my S4 and S5 turbos without taking them apart. I know this isn't the preferred way, but I wedged paper shop towels down the runners and covered the rear of the turbo wheel. I vacuumed out the shavings every couple of minutes and indirectly used compressed air to blow them out as well. I have thousands of miles on my S4 turbo with no ill affects. Just be careful.
03-15-13, 10:36 PM
#12
^^^When I test closed mine it fit flush just about any way I tried. And I'd say I limited my porting somewhat as well. The issue I'm having isn't a result of porting out or making the hole wider. It's a combination of possibly porting down a little bit and how the wastegate arm torque's the flapper shut. When I ported out to enlarge the hole, the edges weren't super clean. So I slightly rounded the edges to soften the transition from open to close. I didn't port it down really, just rounded the edge.
I've talked to someone with an S4 engine with S5 turbo running about stock boost, maybe 10 psi, and he said he doesn't have any issues with boost creep. So you may not have to port yours if you plan on lower boost levels. I think I'll end up around 10-12psi and since I had it sitting on my work bench, I decided to port this one too just to be safe.
And I ported both my S4 and S5 turbos without taking them apart. I know this isn't the preferred way, but I wedged paper shop towels down the runners and covered the rear of the turbo wheel. I vacuumed out the shavings every couple of minutes and indirectly used compressed air to blow them out as well. I have thousands of miles on my S4 turbo with no ill affects. Just be careful.
I've talked to someone with an S4 engine with S5 turbo running about stock boost, maybe 10 psi, and he said he doesn't have any issues with boost creep. So you may not have to port yours if you plan on lower boost levels. I think I'll end up around 10-12psi and since I had it sitting on my work bench, I decided to port this one too just to be safe.
And I ported both my S4 and S5 turbos without taking them apart. I know this isn't the preferred way, but I wedged paper shop towels down the runners and covered the rear of the turbo wheel. I vacuumed out the shavings every couple of minutes and indirectly used compressed air to blow them out as well. I have thousands of miles on my S4 turbo with no ill affects. Just be careful.
I only want 9 psi or less since my ecu and fuel pump are stock. I do have a fuel cut defender and bigger secondaries (gsl se 680cc, which are 720cc on fc).
I still have to get them all cleaned and flow tested.
03-20-13, 04:00 PM
#15
Freshly Built Streetport
Thread Starter
Join Date: May 2010
Location: Minneapolis, Minnesota
Posts: 206
Likes: 0
Received 0 Likes
on
0 Posts
Update. I spent some serious time working with the wastegate arm and flapper arm to see if I could find a way for the flapper door to close flat and seal the openings. I unbolted one of the 2 wastegate actuator bolts to allow me to try different angles of the arm pulling the flapper shut. There were a couple of angles that closed it flush, but if I put any pressure on the flapper door, it would open back up a little. So that wouldn't work under any exhaust pressure. I tried different washer/spacer combos on the actuator bolts as well. Still no luck.
The issue was still the flapper arm and door having way too much play due to a worn out bushing in the housing as suggested above by a few people. So I took the tiny clip that holds the wastegate arm on the flapper arm and wedged it in between the flapper arm and housing. That acted as a second bushing, held the flapper in place, and allowed the flapper to close correctly with the original amount of pressure of the flapper. But after a few test openings, the clip fell out.
So I went and bought a few 'e' clips of various sizes for testing. All were too thick, so I tried thinning them with my dremel. It was very tedious, but as I was just about to get it to the right thickness, it snapped in half, flew out of my vice, and disappeared into my rafters. Next option was a thin piece of stainless shim metal. I cut that into a U shape and slide it into place. It worked. It takes no more effort to open the wastegate than before, keeps the flapper from sliding around, and it seals flat every time. After a number of test openings, it started to work its way out, so I took 2 little dabs of JB weld to hold the shim to the flapper arm. It's a very small amount that can easily be removed if I have to. And if it fails, it'll just fall out my engine bay and my boost reponse will be slower.
Sorry for the novel. But I figured I'd share my fix. It looks DIY for sure, but my wastegate seals right and hopefully it'll work. Thanks for all the help above and I'll update in a couple of months when everything is put back together.
The issue was still the flapper arm and door having way too much play due to a worn out bushing in the housing as suggested above by a few people. So I took the tiny clip that holds the wastegate arm on the flapper arm and wedged it in between the flapper arm and housing. That acted as a second bushing, held the flapper in place, and allowed the flapper to close correctly with the original amount of pressure of the flapper. But after a few test openings, the clip fell out.
So I went and bought a few 'e' clips of various sizes for testing. All were too thick, so I tried thinning them with my dremel. It was very tedious, but as I was just about to get it to the right thickness, it snapped in half, flew out of my vice, and disappeared into my rafters. Next option was a thin piece of stainless shim metal. I cut that into a U shape and slide it into place. It worked. It takes no more effort to open the wastegate than before, keeps the flapper from sliding around, and it seals flat every time. After a number of test openings, it started to work its way out, so I took 2 little dabs of JB weld to hold the shim to the flapper arm. It's a very small amount that can easily be removed if I have to. And if it fails, it'll just fall out my engine bay and my boost reponse will be slower.
Sorry for the novel. But I figured I'd share my fix. It looks DIY for sure, but my wastegate seals right and hopefully it'll work. Thanks for all the help above and I'll update in a couple of months when everything is put back together.
03-20-13, 04:13 PM
#16
try calling Bryan at BNR and see how much he would charge to redo the bushing, you've gone this far you may as well get it done right.
that area will melt just about any adhesive and even most e-clips will warp under the heat and eventually fall off, so they're just temporary fixes for the real problem which is the worn bushing.
that area will melt just about any adhesive and even most e-clips will warp under the heat and eventually fall off, so they're just temporary fixes for the real problem which is the worn bushing.
03-20-13, 04:22 PM
#17
I'd be interested in how much that'd cost myself, I still havent ported my wastegate.
Kevin told me you can port it without taking it apart because the exhaust side only goes out not in, and I could just blow out/suck up what metal is left inside?
I'd be more comfortable taking it apart to do it but I'm worried about breaking bolts. How often.do they break?
Regardless I think my bushing is f'ed because it.doesnt feel tight.
Kevin told me you can port it without taking it apart because the exhaust side only goes out not in, and I could just blow out/suck up what metal is left inside?
I'd be more comfortable taking it apart to do it but I'm worried about breaking bolts. How often.do they break?
Regardless I think my bushing is f'ed because it.doesnt feel tight.
03-20-13, 04:27 PM
#18
they don't often break but sometimes they will bind on the way out.
i have ported them without disassembling but i always prefer to just take the snail off and not get debris inside the turbine housing/wheel, some metal may get under the carbon shield and float around in there indefinitely. you also have to cover up any open ports like oil feed and return lines as well as compressor inlet and outlets. it takes almost as much time sealing up the turbo as it does taking the snail off.
the arm on the S5 needs to be bent to port the wastegate regardless, so either method still doesn't get around that fact.
the S5 turbos are almost all getting to the point that the bushings need attention, otherwise i see little benefit having it for the additional response although it will still have better boost creep elimination capability.
i have ported them without disassembling but i always prefer to just take the snail off and not get debris inside the turbine housing/wheel, some metal may get under the carbon shield and float around in there indefinitely. you also have to cover up any open ports like oil feed and return lines as well as compressor inlet and outlets. it takes almost as much time sealing up the turbo as it does taking the snail off.
the arm on the S5 needs to be bent to port the wastegate regardless, so either method still doesn't get around that fact.
the S5 turbos are almost all getting to the point that the bushings need attention, otherwise i see little benefit having it for the additional response although it will still have better boost creep elimination capability.
Last edited by RotaryEvolution; 03-20-13 at 04:30 PM.
03-20-13, 04:40 PM
#19
Freshly Built Streetport
Thread Starter
Join Date: May 2010
Location: Minneapolis, Minnesota
Posts: 206
Likes: 0
Received 0 Likes
on
0 Posts
I got this turbo practically for free, and the intent has always been to get a BNR stage 2 anyway. Though I didn't mention that above. I just figured I'd run the turbo as is this summer since there is basically no shaft play. It'll probably see 1,000-2,000 miles max this summer.
03-20-13, 04:45 PM
#20
then just run it as is and forget about the sloppy wastegate arm. last thing you want is the wastegate to bind up and overboost just for the sake of some responsiveness. as the turbo heats up and if the clip doesn't fall out it may wind up being the pin out of the grenade, metal expands and it needs room to breathe.
03-28-13, 08:17 PM
#23
Digging up this old thread since I didn't want to make a new one since I have a question.
I'm going to be porting my s5 Turbo wastegates shortly in the future and I need to know how much porting is required to run stock boost 6-7psi with a full exhaust (3" I believe) , with a stock intake/air box.
I know you're probably wondering why I have a full exhaust if I want to run stock boost and the reason is because the car came with it.
I'm going to be porting my s5 Turbo wastegates shortly in the future and I need to know how much porting is required to run stock boost 6-7psi with a full exhaust (3" I believe) , with a stock intake/air box.
I know you're probably wondering why I have a full exhaust if I want to run stock boost and the reason is because the car came with it.
03-28-13, 08:48 PM
#24
I have full 3inch turbo back exhaust with the stock TID/airbox with my s5 turbo waste gate slightly ported.
On warm days I boost 7-8 pounds in 3rd and 4th gear.
On a cold night I have seen 10-11 pounds in 4th gear.
I completely regret getting a full 3inch exhaust because of the boost creep.
So now I have RC 750cc's, I just need a FD pump and Rtek 1.7 so I don't blow my fresh engine. Which is fine because I have upgrades planned for the future.
I should have started with a more conservative exhaust in my opinion.
On warm days I boost 7-8 pounds in 3rd and 4th gear.
On a cold night I have seen 10-11 pounds in 4th gear.
I completely regret getting a full 3inch exhaust because of the boost creep.
So now I have RC 750cc's, I just need a FD pump and Rtek 1.7 so I don't blow my fresh engine. Which is fine because I have upgrades planned for the future.
I should have started with a more conservative exhaust in my opinion.
03-28-13, 09:10 PM
#25
I have full 3inch turbo back exhaust with the stock TID/airbox with my s5 turbo waste gate slightly ported.
On warm days I boost 7-8 pounds in 3rd and 4th gear.
On a cold night I have seen 10-11 pounds in 4th gear.
I completely regret getting a full 3inch exhaust because of the boost creep.
So now I have RC 750cc's, I just need a FD pump and Rtek 1.7 so I don't blow my fresh engine. Which is fine because I have upgrades planned for the future.
I should have started with a more conservative exhaust in my opinion.
On warm days I boost 7-8 pounds in 3rd and 4th gear.
On a cold night I have seen 10-11 pounds in 4th gear.
I completely regret getting a full 3inch exhaust because of the boost creep.
So now I have RC 750cc's, I just need a FD pump and Rtek 1.7 so I don't blow my fresh engine. Which is fine because I have upgrades planned for the future.
I should have started with a more conservative exhaust in my opinion.
The only thing I can do is put gsl se injectors for secondaries (720cc I believe on fc fuel pressure).