We've been trying to do this for a while, and finally followed through for all of you guys;

https://turbosource.com/blogs/news/e...yno-comparison

 

For lazy people who aren't inclined to click the link-

The linked content shows a lot more than the attached picture!

 

great data mate

 

Good stuff! The 8374 continues to be my idea of the best overall powerband. I only wish it didn't appear to surge on anything less than a half-bridge port. Although it doesn't seem to be causing people issues so far, not that I've seen reported anyway.

 

My guess is that, the surge only happens in a split second (2500-3000RPM with a stock port?) that virtually no one will notice it. As long as the engine is not loaded with low rpm and high load (e.g. 5th gear 40 roll), the surge will not be noticable.

 

We are going to do the 8374 vs 9180 next on our shop FC. Large streetport this time, both high and low boost.

 

i'm trying to decide between the 9174 or 9180, any ideas?
the 9174 in theory should have better spool, but the wheel ratio is not ideal.

 

Porting, and power goals all affect this. If you want to know more, and are looking to purchase one just call our office. 763 753 9939.

 

Or just hit me up. There's plenty of documentation on both. Absolutely depends on what you're doing with the car, where you plan on driving it, motor porting, exhaust system capabilities (size/fitment and noise level), and overall budget. Looking back at my build, I would personally go EFR9180 w/ Aluminum CHRA and 1.45 A/R given my newer power plans. It's less responsive than a 9174 w/ 1.45, but overall output should be higher throughout the curve. Really depends on WHERE and HOW you drive.