Yea I don't have any sort of boost controler yet. Will a MBC help out my problem . ..I havn't heard too good of things about mbc's

 

A boost controller won't help, as they can only raise boost from what you have now. Electronic or manual doesn't matter, neither can lower boost.

 

can t you use a MBC to get more boost earlier on in the rpm's??

 

I don't want to lower boost, I guess I phrased that wrong. I want to maintain steady boost. . like a consistant 10psi none on this 10psi bleeding off to 7 or 8 ****. I want stability! lol I don't think a MBC could offer me that. . lol Like I said, I've got the supporting mods, and I also have a set of 720's comming soon for secondaries so I just want to keep boost from falling off. And i'm afraid if I put my 3inch TID on it will get too much boost creap. Maybe I'll play with it and find out. We'll see.

 

If you're reaching 12psi without a boost controller, you will not be able to get a consistent 10psi with one. You might get a consistent 12psi.

 

but wut u dont get is karack is a certified mechanic and has his own rotary shop....so id take his word before just some random person >< but ya i have no idea wut im saying :P

 

Oh man, yes I understand that I can not lower my boost. . I was using the number 10 as a hyothetical number. . haha But anyways, all is going well. No crazy deterioration of the washer hahaa boost is still comming on very smoothly.

 

Maybe I shouldn't have posted pictures of my turbos online!! hehe. I was the only one doing that years ago, now it looks like people are wanting to take my job.

Bryan

 

welds broke. . lol a long time ago so I welded on a new washer my self this time and the welds held great but I took the turbo and manifold off the otehr day and my manifold is cracked like crazy the flange is warped and the washer disintigrated. . lol I had a SSAC mani on there. . just htought I'd take one for the team and see if the new design was any good. . it isnt. . lol but yea the washer did fall apart. I'll have to get a better washer this time.
Dom

 

yeah, thats why i would go with the honduh valve mod. i don't see a valve desintegrating.


but i still don't get it, i don't see why i am able to keep boost creep under control with a smaller wastegate. every wastegate i've modded is holding at 8psi or below even my hybrid with the stock flapper regardless of engine mods because i have customers with varying setups and none of them are having boost creep issues.

 

Ya beat me to it. Thats what I used to port mine.
Jeremy

 

while my turbo is out I'm going to shape the wastegate better and make it so that the flapper can open further. I feel like that is one of the biggest hinderences boost control.

 

i did back cut the door a little but iirc the wastegate actuator just doesn't move that far anyways.

 

I just installed a HDR 3" TID on my TII and I can no longer go past 4.5k RPM's in 3rd gear at WOT without the boost creeping to 13+ psi... Granted, I didn't port the WG--so I have no idea what it looks like. The previous owner of my TII said that it's *not quite* ported to the diameter of the stock flapper, so I guess I should probably have another go at it. I still haven't "tested" to see what the "max creep" is, because I'm paranoid of my 9:4 rotors... It's probably not more than 14psi, but I don't want to find out, lol.

Even with my Profec-B turned off, it's still creeps that much. It used to only creep to around 10-11psi before the TID. Crazy how much difference a $15 HDR TID can make.

 

yea no joke, I'd definetly pull the turbo and port the wastegate more if I were you. Mine's at like 36mm+ I think. I might go bigger. . we'll see

 

we need to clear up some of the common misconceptions with stock turbos and boost control here...


this is because boost control (AKA the altering of the wastegate signal) has nothing to do with how much air the wastegate can physically flow.

hey karack,

the boost control probably has nothing to do with his problem.

the wastegate cant flow enough air in the midrange causing the boost to creep up, then by the time he gets to the high rpms the turbo itself can't flow enough air, causing the boost to bleed down.

stock turbos usually creep AND THEN bleed boost and it has nothing to do with wastegates or boost control or vacuum lines. the stock turbos on these cars will not support enough airflow to hold boost til redline; no boost controller will fix that. the wastegate wont keep up either, which is why the boost creeps up before it drops off.

 

1-2psi of boost creep is still boost creep.

 

Thats nothing, I'm installing a tial 38mm on Node's stock turbo setup

 

hahaha that's great. I think if I end up going with a hybrid I will try to adapt an external setup . . the only thing that sucks is that the stock manifold is cast iron. . and cast iron sucks to weld. Have to pre-heat it and all that good stuff. We'll see though

 

Home Depot Motorsports : Classic!

I should make a trip there soon

 

I believe I posted this somewhere else; but with my recent WG porting, I've gotten the boost down to around 8psi WOT in all gears. I did a lot of back-cutting, took off a fair amount of material on the turbo's back-plate and opened up my port a little more (it was already at the stock-flappers edge. But yeah, a steady 8-9psi with my mods, all the way to redline. That's a 4-5psi improvement from taking off more material from a WG that had already been ported to the edge of the stock flapper. I can now attest that not all WG ports are the same.

 

big intake, big exhaust, and big wastegate. i could hold 5.5psi all the way to redline in every gear. sadly though, the welds were weak and the door is in the middle of the road somewhere. used an exhaust valve.

and boost falling off......you are half correct in that the turbo can't keep up, but that's because the wastegate remains open rather than closing to maintain boost. once the wastegate opens, that's it. i won't close a bit until you let off the gas. i know for a fact that my S4 turbo could maintain 20psi all the way to redline. but ONLY if the wastegate never opens to begin with. EBC, MBC, whatever you choose, your boost will fall off at high rpms. even if the boost controller stops sending a boost signal to the wastegate, the exhaust pressures are too great to allow the flapper door to close. the wategate spring isn't strong enough.

 

you could hold 5.5 til redline because the turbo isnt a limiting factor in airflow for the whole setup at only 5.5psi. it doesnt become a restriction until you are running higher boost like 9,10,11+


that doesn't make sense.

i'm not only half-correct:

if the turbo was keeping up with the airflow demanded by the motor at the given boost level, the wastegate *wouldnt need* to be closed off to maintain that boost level.
the wastegate has nothing to do with how much air the turbo can flow.

the turbo can only flow X air, the engine is demanding MORE air than the turbo can support, so the boost drops down to the point where the turbo CAN keep up.

 

i ported the **** outa mine and it held just barely over stock boost... i also welded a washer in their...this summer (soon) its coming out for my new turbo to take its place..im curious to see whats left of the washer...

 

it's looking like i'll be getting a hybrid to4b soon, the wastegate is already ported but i'll be porting it a bit more most likly. Not making it bigger, just gonna make it smoother and all that good stuff. Does anyone know what's involved in "clipping" the exhaust wheel on our turbos? I know Brian at BNR does this to help hold boost better. . I'd like to look into doing this but don't know what is involved in it. thanks
Dom