Begi s4 overboost > looking for advice.
#41
Boost Czar
iTrader: (62)
Join Date: May 2005
Location: Chantilly, VA
Posts: 79,736
Total Cats: 4,126
I'm pretty sure if you remove that extra divdier they added, you'll be able to control boost better since diverted gas can just flow through the main tube as well...
#42
I agree. If you google image downpipe you'll end up staring at a ton of diesel and subaru dps but a vast majority of them collect into one big collector.
I'm kind of fair weather when it comes to my miata cause it's just a project but maybe some day i'll update my build thread and throw some logs in there. I understand the benefits of an EWG but since i put that spacer in my IWG has been rock solid.
The efr lineup is regarded as having a good internal wastegate right? I have been in and out the last year so unless the consensus has changed perhaps take a look at that turbo. The reason it has that long profile is in part because of how the wastegate operates. It opens inside the turbo body and flows with the exhaust unlike the gt series that needs a little porting help. At least that's my take/analysis on it at first glance.
I'm kind of fair weather when it comes to my miata cause it's just a project but maybe some day i'll update my build thread and throw some logs in there. I understand the benefits of an EWG but since i put that spacer in my IWG has been rock solid.
The efr lineup is regarded as having a good internal wastegate right? I have been in and out the last year so unless the consensus has changed perhaps take a look at that turbo. The reason it has that long profile is in part because of how the wastegate operates. It opens inside the turbo body and flows with the exhaust unlike the gt series that needs a little porting help. At least that's my take/analysis on it at first glance.
#46
Former Vendor
iTrader: (31)
Join Date: Nov 2006
Location: Sunnyvale, CA
Posts: 15,442
Total Cats: 2,104
The efr lineup is regarded as having a good internal wastegate right? I have been in and out the last year so unless the consensus has changed perhaps take a look at that turbo. The reason it has that long profile is in part because of how the wastegate operates. It opens inside the turbo body and flows with the exhaust unlike the gt series that needs a little porting help. At least that's my take/analysis on it at first glance.
https://www.miataturbo.net/prefabbed...2/#post1272746
If you don't speak datalog, this is a 2-3-4 pull showing 141kpa (6psi) at redline. Zero creep. EFR IWG FTW.
6ENsM8Y.png
#53
LownSlow I think you are better off looking into porting. From my reading that seems to solve most people's creep issues on similar setups. Thats what I would do if I were you anyways.
Those EFRs are awesome. Do want.
I get carbide burrs in the mail today. Ill probably have the car back on the road this weekend and see how well opening up the wastegate hole a little and smoothing out the current port job does. I think krissetsfire is onto something though. I bet the flapper itself is blocking flow when open.
Those EFRs are awesome. Do want.
I get carbide burrs in the mail today. Ill probably have the car back on the road this weekend and see how well opening up the wastegate hole a little and smoothing out the current port job does. I think krissetsfire is onto something though. I bet the flapper itself is blocking flow when open.
#55
When you buy a turbo kit from BEGI one of the things they do as part of their setup is port the turbo if it is one that needs it. I got my 2560r from them and Corky did a fine job with getting it to flow properly.
Before I modified my downpipe I would creep from 6 to 8 after i upgraded to 3" exhaust. 2.5" exhaust was maybe half a psi creep.
so that means good work on the turbo port.... mediocre on the dp
Before I modified my downpipe I would creep from 6 to 8 after i upgraded to 3" exhaust. 2.5" exhaust was maybe half a psi creep.
so that means good work on the turbo port.... mediocre on the dp
#59
Just put the car back together after opening up the wastegate hole and smoothing out the channel Begi made. Results? Car feels incredibly slow Peaked at 12-14psi where it peaked at 16+psi previously and it made ~2psi less everywhere after turbo spooled. VD puts the power around 240hp on a dynojet. AFRs were very rich so I'll have to retune WOT but I assume after they are dialed in I will be right around 250 again. I can't comfortable run a MBC to help spool anymore (its kinda terrible right now) but if it keeps my motor alive I am a happy camper.
Thanks everyone for your contributions in this thread!
Thanks everyone for your contributions in this thread!
#60
your wg "port" on the elbow is more than enough
Just put the car back together after opening up the wastegate hole and smoothing out the channel Begi made. Results? Car feels incredibly slow Peaked at 12-14psi where it peaked at 16+psi previously and it made ~2psi less everywhere after turbo spooled. VD puts the power around 240hp on a dynojet. AFRs were very rich so I'll have to retune WOT but I assume after they are dialed in I will be right around 250 again. I can't comfortable run a MBC to help spool anymore (its kinda terrible right now) but if it keeps my motor alive I am a happy camper.
Thanks everyone for your contributions in this thread!
Thanks everyone for your contributions in this thread!