Anyone know? I have a .82 and would like to get something bigger. Any options? Thank you.

-Chris

Just wondering why you would want to go bigger than a .82 T4? I run a 0.81 T4 P-trim housing on my T70, and I don't think Id ever go bigger.

I'm getting boost creep in 3rd gear+, and changing an exhaust housing is easier than changing my manifold and all supporting hardware.

Sounds more of an exhaust wastegate issue to me.

Yes me too but I've been down every path imaginable to try to solve this. My car has been sitting since december because of this and I'm about ready to throw in the towel. Tonight I made the wastegate open dump and still no better. The light at the end of the tunnel is looking dim.

Yes me too but I've been down every path imaginable to try to solve this. My car has been sitting since december because of this and I'm about ready to throw in the towel. Tonight I made the wastegate open dump and still no better. The light at the end of the tunnel is looking dim.

Ever think about just turning up the boost :D

I think Mike said that open dump would cause more creep than a routed back one.

Ever think about just turning up the boost :D

I think Mike said that open dump would cause more creep than a routed back one.

Not sure how that'd work - dumping you are releasing exhaust pressure to ambient which is much lower pressure, so you don't have any back pressure issues. Routing in can have reversion effects that will create creep.


Chris aren't there like tons of dudes running this manifold? I mean jay and I both have one now with similar design/placement, and jay was able to run like 12 psi or so I think

Chris aren't there like tons of dudes running this manifold? I mean jay and I both have one now with similar design/placement, and jay was able to run like 12 psi or so I think

Yep. Just my luck, huh? On the bright side, I now have a downpipe combo for recirc and dumped. And I can scare children at will. :devillook

Ever think about just turning up the boost :D

Yes but I think 21 psi base boost is a bit much for a stock S50.

mine always creeped. i really don't remember what spring i have, but i think its a 10. i used to hit 13 with it.

Best suggestion. raise the boost and run a boost controller. Then you will have a whole nother set of issues :D

i think the boost rises so fast with the gt35r that its hard to control it at lower levels. and then throw in gear dependencies at it gets :eyecrazy

yeah - but damn 10 to 13 is not bad. I had 8.7 spring and creeped 10 or so. Then I electronically creeped 15

Jay aren't you supposed to be entertaining :)

Not sure how that'd work - dumping you are releasing exhaust pressure to ambient which is much lower pressure, so you don't have any back pressure issues. Routing in can have reversion effects that will create creep.


Increasing the backpressure with hot gases behind the turbo will slow the turbine down. Makes sense to me.

Do have your waste gate signal from the manifold or charge pipe? How much boost are you trying to run and how high is it spiking?

And check your vacuum lines for a tiny cut or puncture. If you have silicone vacuum lines, a small cut can be hard to see until you bend the hose.

Ive found a couple small slices in my silicone vacuum lines, and even had one split right on the waste gate fitting, just barely hanging there(though I think that was mainly from too much heat from the exhaust manifold, its heat shielded and fine now).

tried getting the WG signal right off the turbo? or is that not an option on that one without drill/tap

I've used a vacuum pump on the top port of the wastegate to pin the plunger WIDE OPEN, and it still creeped by rev limiter. Its not a vacuum hose issue unfortunately.

what manifold and wastegate do you have.. just curious

666 bottom mount, genuine TiAL 44mm, GT3582r with .82a/r hot side.

I look at it like I have four options:

1. Hook up my boost solenoid, run a flat 20 - 23psi all over, add water injection for safety.
2. Build a motor and shoot for 25psi at all times.
3. Get a GT4088 / 4094. But-- To utilize the real potential of a 40r, that brings me back to step 2.
4. Change my exhaust manifold, turbine housing (t3), and everything around it (exhaust / intercooler piping / intake). My least favorite option.

You have a 3" exhaust? cat?

Chris I think if you went to a GT40 (which you should have done originally ;) ) you will just fling past that boost level again - the larger the turbo, the more airflow its going to want to breathe - I don't think you could get a GT40 down in psi and if anything you'd be up!

Chris I think if you went to a GT40 (which you should have done originally ;) ) you will just fling past that boost level again - the larger the turbo, the more airflow its going to want to breathe - I don't think you could get a GT40 down in psi and if anything you'd be up!

Well idk, tough call because the exhaust side will need significantly more flow to make the same boost. But yes, the added compressor flow would probably compound the issue. :eyecrazy Really a tough call.

I wonder if switching the vanos off higher could keep it down to say 18psi? Maybe switching it higher would help VE and make less 'boost' because the engine is breathing better?

You have a 3" exhaust? cat?

3" from turbo to a large single magnaflow dual tip. No cat.

Have you tried out your Autronic EBC yet?

Have you tried out your Autronic EBC yet?

Not yet, just running wastegate spring.

i doubt a new housing will make a difference. I ran my car with a .68 housing with a 38mm WG and never had creep issues. just get a proper EBC and call it a day...

what WG spring are you running?

I've used a vacuum pump on the top port of the wastegate to pin the plunger WIDE OPEN, and it still creeped by rev limiter. Its not a vacuum hose issue unfortunately.

just get a proper EBC and call it a day...

what WG spring are you running?

.9 bar (13 psi)

does it ever hold a steady 13 psi? what rpm does it usually spike at?

.9 bar (13 psi)



ok, and it spikes to about 20psi?

that seems a bit odd. does the manifold have a wg port at least 38mm?

when i would run on my wg spring (8psi) i would get about 10psi of boost.


something seems odd, but I DOUBT it's the housing...

does it ever hold a steady 13 psi? what rpm does it usually spike at?

Yes it will. Hard to say though, once the boost is on, I'm trying to stare at the road and not the gauge. I haven't taken any datalogs since I fixed my massive boost leak. I would guess until 4800 - 5000rpm it holds 13psi, the flies up from there.

ok, and it spikes to about 20psi?

that seems a bit odd. does the manifold have a wg port at least 38mm?

when i would run on my wg spring (8psi) i would get about 10psi of boost.


something seems odd, but I DOUBT it's the housing...

I know its not the housing at fault, but a larger housing could keep the boost down as it would require most exhaust flow through the turbine to make the same boost... Then maybe there would be enough headroom, and the wastegate could keep up.

The WG port is 44mm. Unfortunately, because of the space constraints, wastegate placement is less than ideal.

I know its not the housing at fault, but a larger housing could keep the boost down as it would require most exhaust flow through the turbine to make the same boost... Then maybe there would be enough headroom, and the wastegate could keep up.

The WG port is 44mm. Unfortunately, because of the space constraints, wastegate placement is less than ideal.


dont sacrifice your response to bandaid another problem. there is a problem somewhere...

see if you can try another wastegate...just to get an idea

Where are you feeding boost to the WG from?

do you have anymore wastegate springs? see if tial will send you a new one and diaphram?

you can get a 1.06ar

GT35R has 0.63, 0.82 and 1.06 AR turbines.

you can get a 1.06ar

GT35R has 0.83, 0.82 and 1.06 AR turbines.

1.06 AR, In T4 ? I can't seem to find them. Care to share guys? Thank you.

-Chris

Not sure how that'd work - dumping you are releasing exhaust pressure to ambient which is much lower pressure, so you don't have any back pressure issues. Routing in can have reversion effects that will create creep.


Depending on the angle of the recirculation tube - the wastegate can see much lower pressure than atmosheric, even with a static pressure higher than atmospheric in the downpipe.

It's all about the dynamic pressure component of the exhaust gases. It's also how crankcase exhaust evacuation works.

Def, come run some numbers and fix my setup!!! :)

Def, come run some numbers and fix my setup!!! :)

$100/hr engineering fee.



I do have to ask, at what angle does the recirc. tube go into the downpipe. It should be at a 45 deg angle or less. If it's at more than a 45 deg angle, then yea, it is going to creep badly.


I'd also look at going up in wastegate size and porting the WG port a bit. I'd also check to make sure the WG has a full range of travel. If it is binding up without opening all the way that could easily explain the creeping.


I don't think a larger turbine A/R is going to help your creep issue that much if it's as bad as you say now.

How far downstream is your wastegate?

How far downstream is your wastegate?

my 38mm was at least a foot downstream...no problems

I do have to ask, at what angle does the recirc. tube go into the downpipe.

I'd also look at going up in wastegate size and porting the WG port a bit. I'd also check to make sure the WG has a full range of travel. If it is binding up without opening all the way that could easily explain the creeping.

Here is the angle with the WG dump merged:

http://www.smeraglinolo.com/hosted/turbom3/progress/day9/DSC_2293.jpg

I have bench tested the WG and it pins wide open. :(

How far downstream is your wastegate?

I'd guess around 10 - 12 inches from the turbo outlet.

I might see if i can fit another gate on the side of the collector and snake it somewhere. :shifty

Here is the angle with the WG dump merged:
I'd guess around 10 - 12 inches from the turbo outlet.

I might see if i can fit another gate on the side of the collector and snake it somewhere. :shifty
I don't know how much of a diffreence it could make, but my gate pipe runs considerably further downstream than yours and I have no creep with a t3 3582r and a 44mm gate. I can run 12psi all the way to redline in all 5 gears. Good luck.

What does the feed off of the collector look like? If the placement is less than perfect you can have some creep. I couldn't run less than 15psi with my 71mm turbo and a tial 44mm gate(.5bar spring). It wasn't a problem because I need to run in the 20-40psi range.

Hmm, rinochaser-- What turbo manifold are you running?

What does the feed off of the collector look like? If the placement is less than perfect you can have some creep. I couldn't run less than 15psi with my 71mm turbo and a tial 44mm gate(.5bar spring). It wasn't a problem because I need to run in the 20-40psi range.

Mike, here's the mani. Jon even added a little tab after the WG opening in the collector to try to capture more exhaust flow.

http://www.smeraglinolo.com/hosted/DSC_2538.jpg

I'm out of ideas other than another wastegate (which could be impossible) or a new manifold. Would you feel comfortable with 21 psi on a stock S50 ?

time to build an engine and run 20-25psi my friend...i'll help if there's beer..preferably labatt blue...:alright:devillook

time to build an engine and run 20-25psi my friend...i'll help if there's beer..preferably labatt blue...:alright:devillook

That might be my next move, Des. I'm all for it but my bank account is yelling at me. :shifty

the 1.06ar is out there just call a few of garrets distrubuters good luck

Mike, here's the mani. Jon even added a little tab after the WG opening in the collector to try to capture more exhaust flow.

http://www.smeraglinolo.com/hosted/DSC_2538.jpg

I'm out of ideas other than another wastegate (which could be impossible) or a new manifold. Would you feel comfortable with 21 psi on a stock S50 ?

There's your problem. It looks like you'd only be putting the most rearward cylinders into the wastegate tube. The exhaust gases won't want to "stop" and turn from the forward cylinders to get to the WG tube.

Hmm, rinochaser-- What turbo manifold are you running?
I'm using a spa manifold, but I ported the gate port on the manifold to about the same size as the inside diameter of the 1 3/4 dump tube.

1.06 only comes in a T3 not T4

There's your problem. It looks like you'd only be putting the most rearward cylinders into the wastegate tube. The exhaust gases won't want to "stop" and turn from the forward cylinders to get to the WG tube.

So were would a better placement of that WG tube be on this manifold? Or is it really the amount of exhaust gases that is getting him into trouble? I am just trying to figure this out before I run into the same problems down the road.

OT: If you sell the T4 GT35R let me know. I would definitely be interested..:)

OT: If you sell the T4 GT35R let me know. I would definitely be interested..:)

The housing or the turbo? I may be...

So were would a better placement of that WG tube be on this manifold? Or is it really the amount of exhaust gases that is getting him into trouble? I am just trying to figure this out before I run into the same problems down the road.

With a collector that "wide" you likely need to have two tubes coming off the collector to the WG. Probably not possible with the space there, but it'd likely solve the issue.

GT35R has 0.83, 0.82 and 1.06 AR turbines.
.63 nubz;)

if you take a look at rrdawho's? build he just recently got his car runnin and was having bad boost creep as well. He fixed his problem by installing a cat. This could help you out alot by slowing down the flow of your exhaust. also in order fo the wastegate dump to work correctly the dump pipe needs to actualy enter the downpipe so that its able to create a vacuum to help pull out the pressure. looks like your dump is flush to the down pipe. its kinda hard to explain. Id be willing to bet if you installed a cat or resonator it will help aid you in your creep issues.

http://www.vecco.com/products.php?sub_cat_id=11
This site has p-trim, undivided tangential housings in .58, .68, .81, and .96, as well as a Q-trim in .96. Really sounds like you have a different problem, though. Good luck resolving.

Id be willing to bet if you installed a cat or resonator it will help aid you in your creep issues.

Yeah I was debating this. Hmm...

http://www.vecco.com/products.php?sub_cat_id=11
This site has p-trim, undivided tangential housings in .58, .68, .81, and .96, as well as a Q-trim in .96. Really sounds like you have a different problem, though. Good luck resolving.

Very nice find! Thank you for the link. I agree I suppose a larger housing is just a bandaid. Ahh well, I'll figure it out sooner or later... I hope.

.63 nubz;)
Oops, yep sorry typo.

Also that info is good for T3 flange, I don't know about T4.

The housing or the turbo? I may be...

turbo. Although it seems like you are only interested in another housing..

Swap in a gt42R and stop messing around

Damn I was just running some numbers. Parting this stupid car is looking like a nice option at this point..........or built motor? :dunno

Jon, you'll have PM in 1 sec.

Got PM and repliedz

i'll take the WG if you wanna go 60mm :D

Well Chris, Now that I have read through this thread, I am concerned with the 666 manifold. I do intend to run an EBC, so maybe that will alleviate some of the problems you are having.

I see that you are currently suspended. When you get free, shoot me a PM. Since my parts are similar to yours, I'd like to know a few things. Thx

He can PM while in TO, so you might as well go ahead and get in touch with him. :)

Parting this stupid car is looking like a nice option at this point..........

I've been there SOOOOOO many times. :(

He can PM while in TO, so you might as well go ahead and get in touch with him. :)


I didn't know that. I've never been in TO:D

Chris has since PM'ed me ....kthx