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We are working on the mold for these currently and will be doing a run of 200+ units to get started. We have already worked out all of the linkage etc, which isn't pictured here. This is a direct replacement for the EFR IWG 74mm turbine housing( 8374, 8474, 9174, and 9274).
Improvements are;
Large A/R; 1.0 ( vs Borg .92)
Much larger Wasetgate runners( better boost control)
Better turbine discharge( interlocking flanges can be used, but one doesn't have to).
This unit will bolt into existing turbo kits without any fabrication changes.
All of our 74mm EFR turbo kits will be using these by default when available. High chance we start on an 80mm version shortly after. We have a long list of turbine housings are are currently developing also, including some Garrett G series models.
Are these housings going to affect the ability to run the air pump with the cast manifold? I'm looking at upgrading to an efr 8374 in the near future, but still need the air pump for emissions.
Very nice! Very keen to see if the improved wastegate runner design means an EFR8374 IWG can be safely run at low boost levels with free flowing exhaust. That would be a massive plus for street cars and make the 8374 IWG and even better all round choice for the 13B.
Are these housings going to affect the ability to run the air pump with the cast manifold? I'm looking at upgrading to an efr 8374 in the near future, but still need the air pump for emissions.
These housings don't change current fitment. So you can still fit an airpump, just required extending the lower tension( or making a new one ) , and some grinding on the casting extensions.
Very nice! Very keen to see if the improved wastegate runner design means an EFR8374 IWG can be safely run at low boost levels with free flowing exhaust. That would be a massive plus for street cars and make the 8374 IWG and even better all round choice for the 13B.
Although we havent tested them yet, they absolutely will help with boost contol. We know this, because simply porting the borg unit fixes 90+ percent of all boost creep issues. The wastegate runners are even larger than when porting, but retains the fully divided orientation( so one doesn't lose the 250+ rpms of boost response ).
Here is probably what most of you want to see in terms of the changes in terms boost control, there is more done than just shown here, but I am not going to show off everything we have worked on.
Did you bail on the internal twin scroll diversion flap design?
It appears that the scrolls shifted out to the side more than vertically relative to the BW design? Just trying to get a feel for fitment in other applications.
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Did you bail on the internal twin scroll diversion flap design?
It appears that the scrolls shifted out to the side more than vertically relative to the BW design? Just trying to get a feel for fitment in other applications.
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Guessing it wasn't that popular and needed tuning effort to avoid surge.
Did you bail on the internal twin scroll diversion flap design?
It appears that the scrolls shifted out to the side more than vertically relative to the BW design? Just trying to get a feel for fitment in other applications.
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Nope haven't bailed on that, just have a million things going on.
As soon as I have a little bit more run time on the new IWG housing, we are transferring some of those new components over into this application.
Here is our first round of back to back dyno tests.
This was all done within 2 hours of runs, and weather conditions barely moved( it was 93 deg F for baseline, black runs on the OEM .92 housing).
It was 95 deg F for the new turbine 1.0 turbine housing( humidity did drop slightly, but the automated weather correction factor was the same. Each run was started at the same coolant temp( 175 deg F). These were with the OEM Borg medium actuator, and the boost controller offer on E85. This is an 8374 Cast V1 kit thats been on this drift car for 4+ years. On a side note it was cool to see zero issues with the kit.
There was a 75 rpm loss of boost response with the new larger turbine housing, I expected more, but this could be because we started the pulls in 4th gear, and 2k RPMS. Chances are there will be more lag differences in the lower gears. We ran out of time, and had a lot going on to think about this while testing.
HP & TQ jumped considerably across the entire rev range past 3k rpms. I was surprised, I was only expecting half this. We even dropped the pre load way down, and did 10 more pulls back to back HOT, and it was still MUCH higher everywhere vs this baseline cold pull. The turbine housing definitely makes more power. Bad news is the boost creep up top is not fixed. The turbine housing WG flow is definitely more, as midrange boost we were able to drop that by several PSI( dropped down to 12, but would go up to 17 psi past 7k rpms). We are going to try adjusting the CNC program and just cut out the WG divider and see how much that helps( as we do know removing both the WG and T4 divider on the OEM borg housing will drop boost creep by 5+ psi). We are also going to adjust the mold slightly to make the WG runners even larger, as I just spotted an area where we can gain a few more MM in the smallest choke point.
We are moving these into production now, and have 100 being made. Also now drawing up the 80mm unit, and we are going to make that a 1.1 A/R.
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