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ported WG atill boost creep

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Old 03-05-10, 01:15 AM
  #26  
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The S5 turbo has practically double the wastegate flow potential over the S4. I don't see why it would actually cause that much trouble with good exhaust/intake. And on top of that, a hybrid stock turbo will be able to push higher boost levels effectively anyway instead of dumping heat into the charge. 15psi wouldn't be nearly as big of a problem as it is with a strictly stock turbo. I guess at the high BNR upgrade level that is why they clip the turbine wheel, but still.
Old 03-05-10, 03:18 AM
  #27  
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Did you back-cut the runners when you were porting it?

Just opening it up where the flapper seats isn't enough, you have to open it up along the whole length of the runner.
Old 03-05-10, 07:51 PM
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Originally Posted by MaczPayne
Did you back-cut the runners when you were porting it?

Just opening it up where the flapper seats isn't enough, you have to open it up along the whole length of the runner.
if your refering to the hole that was ported, yes it is the same diamiter all the way through
Old 03-05-10, 08:22 PM
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Originally Posted by florotory
if your refering to the hole that was ported, yes it is the same diamiter all the way through

Did you use an endmill to go all the way thru the hole or did you use a boring bar? Looks nice! Was it CNC cut or did you do it on a manual mill?
Old 03-05-10, 09:27 PM
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mines 37mm, backcut, and still creeps, but way better than stock
Old 03-05-10, 10:44 PM
  #31  
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S5 turbo here ported to about a 35mm equivalent, but I also milled out the back plate an 1/8th of an inch to allow the door to open further. 3" TID & 2.5" downpipe, and I have virtually no boost creep.

The other thing that hasn't been mentioned is that the S4 wastegate path only connects to one runner in the turbine housing, while the S5 has separate paths for each.
Old 03-06-10, 07:51 AM
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Originally Posted by RotaryRocket88
The other thing that hasn't been mentioned is that the S4 wastegate path only connects to one runner in the turbine housing, while the S5 has separate paths for each.
While I didn't specifically say it, I alluded to it at the top of this page.
Old 03-06-10, 09:21 PM
  #33  
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Originally Posted by RotaryRocket88
S5 turbo here ported to about a 35mm equivalent, but I also milled out the back plate an 1/8th of an inch to allow the door to open further. 3" TID & 2.5" downpipe, and I have virtually no boost creep.

The other thing that hasn't been mentioned is that the S4 wastegate path only connects to one runner in the turbine housing, while the S5 has separate paths for each.
I thought about milling out the back plate but forgot about it till i put it all back together. I took the car out tonight and it only crept up to 7psi. Im gona try again tomarrow and see how it does
Old 03-07-10, 07:50 AM
  #34  
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ok i lied it still boggs and creeps
Old 03-07-10, 08:20 AM
  #35  
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Originally Posted by SpeedOfLife
The S5 turbo has practically double the wastegate flow potential over the S4. I don't see why it would actually cause that much trouble with good exhaust/intake. And on top of that, a hybrid stock turbo will be able to push higher boost levels effectively anyway instead of dumping heat into the charge. 15psi wouldn't be nearly as big of a problem as it is with a strictly stock turbo. I guess at the high BNR upgrade level that is why they clip the turbine wheel, but still.
the ports on my BNR stage 3 looked like they were not even touched, he just clips the wheel to let more exhaust past the turbine wheel so you dont get creep. the S5 would have a good wastegate setup if it werent for the door literally only cracking open at full travel
Old 03-07-10, 08:23 AM
  #36  
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I wonder if it would be possible to build a spacer for the backplate to allow the flapper door to open more? Any thoughts on that?
Old 03-07-10, 08:42 AM
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I'm sure it would, but would it be worthwhile? eh, idk. You COULD try cutting the wastegate's external flapper arm and welding it back together, shorter than before, that way for the same amount of actuator travel you get it to open farther.
Old 03-07-10, 09:12 AM
  #38  
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Correct me if im wrong here but since i used a pretty big exhaust valve wouldnt it hit the back plate causeing it to only open a small amount which inturn would basically be like porting the WG a small amount?But if it were to open up more it could use all or most of the 30mm or whatever i have it ported too. Just throwing out ideas to get feedback. Maybe if i can get this issue fixed it will help someone else later down the road as well,
Old 03-07-10, 10:48 AM
  #39  
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I typed a bunch of stuff but kinda had a lightbulb go off that you wouldn't understand what i was talking about.

Pick up this:




I dont get it. I've known people to slap 3" exhausts and downpipes on their rotaries for a long time now.....atleast 8 years and i cannot count how many i've seen pop due to boost creep. Ported wategate or not, the hot sides are too freaking small.

https://www.rx7club.com/2nd-generation-specific-1986-1992-17/stock-turbo-wheel-size-818137/#post9498080



Some of you act like it KILLS you to spend $1500 or LESS (yes i said less) on a decent USED aftermarket setup but can afford to put a $500+ exhaust on your car that doesn't benifit you in any way other than teaching you how to rebuild your own engine? Looks shiny and it's jdm so it must be cool.......

No amount of porting that tiny *** piece of **** is going to keep it from creeping when post turbine gas is able to get away from the engine unrestricted where as pre-turbine pressure could probably build boost on an ht-18 with NO wastegate flapper at all.
Old 03-07-10, 01:13 PM
  #40  
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Originally Posted by NoPistons!
I typed a bunch of stuff but kinda had a lightbulb go off that you wouldn't understand what i was talking about.

Pick up this:




I dont get it. I've known people to slap 3" exhausts and downpipes on their rotaries for a long time now.....atleast 8 years and i cannot count how many i've seen pop due to boost creep. Ported wategate or not, the hot sides are too freaking small.

https://www.rx7club.com/showthread.php?p=9498080



Some of you act like it KILLS you to spend $1500 or LESS (yes i said less) on a decent USED aftermarket setup but can afford to put a $500+ exhaust on your car that doesn't benifit you in any way other than teaching you how to rebuild your own engine? Looks shiny and it's jdm so it must be cool.......

No amount of porting that tiny *** piece of **** is going to keep it from creeping when post turbine gas is able to get away from the engine unrestricted where as pre-turbine pressure could probably build boost on an ht-18 with NO wastegate flapper at all.
Maybe they have a budget that doesn't include an aftermarket setup.
Maybe they want stock spool, not the extra lag of an aftermarket setup.

Maybe the world doesn't just work exactly the way you think it should, because if you spend any time reading Corky Bell you will find that he complains about boost creep on most all setups, even his current Miata's.

Here is a thread from a creative guy who has a tight budget. He now has NO boost creep, and stock spool. Why, he could even go with a hybrid turbo with no clipped exhaust turbine. In this thread you will find a link to yet another solution to the problem. Creativity is about to overcome all your objections. Don't live in the past.
Old 03-07-10, 06:47 PM
  #41  
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Originally Posted by NoPistons!
I typed a bunch of stuff but kinda had a lightbulb go off that you wouldn't understand what i was talking about.

Pick up this:




I dont get it. I've known people to slap 3" exhausts and downpipes on their rotaries for a long time now.....atleast 8 years and i cannot count how many i've seen pop due to boost creep. Ported wategate or not, the hot sides are too freaking small.

https://www.rx7club.com/showthread.php?p=9498080



Some of you act like it KILLS you to spend $1500 or LESS (yes i said less) on a decent USED aftermarket setup but can afford to put a $500+ exhaust on your car that doesn't benifit you in any way other than teaching you how to rebuild your own engine? Looks shiny and it's jdm so it must be cool.......

No amount of porting that tiny *** piece of **** is going to keep it from creeping when post turbine gas is able to get away from the engine unrestricted where as pre-turbine pressure could probably build boost on an ht-18 with NO wastegate flapper at all.
i really dont want to to put out the money right now for an aftermarket kit, id rather put that money toward boosting the my e46. So if you wanna be a douche feel free to do it elsewhere. Your entire post did nothing but TRY to insult people. There was absolutley no useful info in it.
Old 03-09-10, 09:11 PM
  #42  
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Originally Posted by RacerXtreme7
SERIOUSLY?? stupidist damned advice I've ever heard.. add a bunch of performance enhancing devices, then weld RESTRICTORS to cancel them out so you can control boost. WTF?? Yeah, go ahead and downgrade every thing you've done, screw doing it the right way and maintain performance.. REALLY? You think a free flowing 3" exhaust with RESTRICTORS performes better then stock 2.25"?

~Mike...........
A bunch of performance parts?

I bought a $170 WG and 10 dollars in metal. Then welded restrictors ( to keep my engine from going to **** ). The only thing that got canceled here was the over boost.

I dont know if a 2.25 stock exhaust flows better or not....whatever. Never had it.

Also, not everyone has disposable income to build engines the best way possible. If that was the case, florotoary wouldnt be asking how to fix his problem. Instead he would be buying a complete turbo upgrade..

Originally Posted by RacerXtreme7
Nice job porting the gate. I have a failsafe solution to your problem. Take the back plate off the turbo, cut a hole out where the flapper is and make sure the flapper when it opens actually opens further then stock and into the new hole you just made. Now weld a tube over the hole and plumb that back into your down pipe 18" or so further downstream. Now make a little divider and weld it to the backing plate effectively separating the turbine discharge hole from where the waste gate used to flow into the same hole. This solves a couple problems. 1: Being it allows your flapper to open farther. 2: It gives your waste gated exhaust a straighter path instead of the hard 90* out the flapper hole, then 90* out the down pipe. 3: It also keeps high heat and velocity of the exhaust existing the turbine from inhibiting waste gate flow. It also enhances turbine discharge if you port the turbine discharge to be shaped like a smooth cone from the turbine wheel to matching diameter of the downpipe. I've suggested this to several friends over the last 10 or so years and all of them it worked and they had rock steady boost of 7 psi on large hybrids running 3" or larger exhaust running after market EMS so no TID. My buddy DCEE on this forum did it about 7 or 8 years ago, you might be able to find his write up. He has a 13b turbo'd 1st gen with a T04E hybrid.

~Mike.............

Interesting.......See I did something like that exept I pitch the flapper door and the actuator to the garbage....and I still had over boost untill I welded my RESTRICTORS. There is one on the top of that crush bend and on the bottom...









This guy has a stock turbo.....

Originally Posted by florotory
If I am unable to keep boost from creeping what should my next step be? Aftermarket WG? Upgrade injectors (or have mine sent out to be cleaned) ? Thanks again for all the help. This boost creep is a pain in the ***
Fuel upgrade will keep your engine a little safer but your little turbo wont last long overboosting all the time.
Old 03-09-10, 09:48 PM
  #43  
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putting the stock TID and air filter back on can help control boost creep.
Old 03-09-10, 09:53 PM
  #44  
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Thanks for the laugh guys!
Old 03-09-10, 11:14 PM
  #45  
whats going on?

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sigh. just run a stand alone ecu and never worry about boost creep.

i run bnr stage one and it creeps all the time. so what? haltech compensates for it and i find it more fun.
Old 03-10-10, 07:02 AM
  #46  
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Originally Posted by K-Tune
putting the stock TID and air filter back on can help control boost creep.
thats no better than welding restrictors in the exhaust.. re-read RacerX's post

Originally Posted by SirCygnus
sigh. just run a stand alone ecu and never worry about boost creep.

i run bnr stage one and it creeps all the time. so what? haltech compensates for it and i find it more fun.
eh thats what Im doing now, i have no low boost setting. I set my wg solenoid to open up at 13psi and let creep do the rest haha
Old 03-10-10, 09:17 AM
  #47  
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I realized that my first attempt with using an exhaust valve was most likely not opening far enough. Durr hurr hurr. I had to extend the actuator rod nearly a 1/4" to reach the closed position of the flapper. So I cut and ground all the extra crap out, making the flapper arm go pretty low. I think it came out well. I was so sad, though, the port was so BEAUTIFUL before I started welding. All shiny and ****. I have a 30mm port now, before it was around 24mm, and it opens farther. It doesn't seal perfectly, but it ought to get the job done quite well. .5mm gap or less. Anyway, I put her all back together last night, but I haven't driven it yet because my driveway is a ******* mud pit. It's not enough that the snow is starting to melt, it has to RAIN, too. Bah.



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Old 03-10-10, 10:24 PM
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I finished the waste gate port yesterday. I STILL creep a little in 4th gear. I have the stock actuator hooked up, no boost controller, so it's as low as it gets without disconnecting the rod and leaving it open all the time. I can run WOT through 3rd hitting about 10-12psi then in 4th it'll try to go to 14-15psi. Haven't fiddled with 5th yet, but it won't be any better. I'm disappointed, but it's a lot better than it was. Just go S5. This **** is ridiculous.
Old 03-11-10, 07:36 AM
  #49  
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Originally Posted by SpeedOfLife
I finished the waste gate port yesterday. I STILL creep a little in 4th gear. I have the stock actuator hooked up, no boost controller, so it's as low as it gets without disconnecting the rod and leaving it open all the time. I can run WOT through 3rd hitting about 10-12psi then in 4th it'll try to go to 14-15psi. Haven't fiddled with 5th yet, but it won't be any better. I'm disappointed, but it's a lot better than it was. Just go S5. This **** is ridiculous.
is that just running on wg spring?

also how much psi were you using in the video? what if you shortened the wg lever so it opens more at lower boost. when i tested my wg actuator, it really didnt get to full travel until 15psi. at stock boost it was only half-way open. or if you found an aftermarket actuator that had more throw?
Old 03-11-10, 09:11 AM
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Yes, that's just the waste gate spring, no controllers. I tested it with 10psi, then 15psi. I don't remember which I used for the video, but I do know that it didn't open any farther using 15psi, so it doesn't make any difference for mine. I do realize I should have tested it at about 7psi, but I don't know what I would have changed if it wouldn't have opened all the way at that pressure, except maybe modify the lever like you mentioned. Kind of wishing I'd done that because there's room for it to open at least another 1/8" at the tip, and I now know that it just barely wasn't enough.

An aftermarket actuator sounds like a decent idea to me, especially in your case. But I think I'm going to leave mine as is for now. It's basically safe to flog through 3rd gear and almost completely for 4th. I don't want to take the turbo out a THIRD TIME if I'm not replacing it with something markedly better.


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