Quick Case Study: “NEW” B58 Pure Turbos

We mention briefly in our B58 Build Path to avoid the “NEW” aftermarket core B58 Pure Turbo offerings and this quick case study is meant to provide some insight for this recommendation.

First off, what changed and why is there an issue? The original B58 Pure 800 turbo is our favorite option in the hybrid turbo B58 arena and we continually see great results with this configuration. This configuration requires sending an OEM core to Pure for upgrade. At some point the “NEW” aftermarket casting was created so that clients no longer needed to send in an oem core for modification. This “NEW” aftermarket housing unfortunately has a very poor wastegate flow design and one bank doesn’t have proper flow out the wastegate so this results in very poor boost control.

What is the fix? Quite simply, ordering the oem core turbo…otherwise heavy porting can alleviate the issue if done properly. This can result in a reduction in spool and the mapping for the turbo will be completely different than the OEM core turbos.

This image is the new aftermarket housing before porting.

First shot at porting; turbo still had heavy boost creep and wasn’t ported enough.

Second attempt at porting; this also resulted in a slight drop in spool but we gained proper boost control.

HOW BAD IS IT? CAN YOU TUNE AROUND IT?

There are definitely ways to control this such as various throttle/load/ignition controls however the wastegate control should always be the primary control. Allowing the constant overboost is not the right way to do this. A quick snapshot of an un-ported “NEW” Pure800 seen below:

In this 5th gear dyno log, we are showing that even with the wastegate forced fully open (0% WGDC = fully open), the boost is still increasing and even with the throttle closing in around 50% the boost is still 4psi over target.

Above is a log after initial porting…this is better but still showcases that it still doesn’t have proper control

The above is what an OEM Core looks like for proper control. As you can see there is quite a big difference in these designs. I recommend sticking with the OEM design which works very well.

SUMMARY AND BEST SOLUTION

Stick with the original solution, if it isn’t broke, no need to fix.