Quote:
Originally Posted by yousefnjr
Can confirm, I just asked them about this a couple days ago. Their response:
"You actually can't run stepped headers on the MSS70. The O2 feedback is completely whack on those."
Of course I realized this after buying their tune and some stepped headers  |
I have two supercharged Z4M's running stepped headers (SS V1 and CPI), so Z4M's can definitely be tuned for them. I know stepped headers are Supersprint's premier S54 product, Evolve is a Supersprint distributor, and Evolve is ESS's competitor. It's a business decision... they either don't want to tune for them because they pay someone else to do their tuning and they can't tune for them in house; or they can tune for them but don't want to support their competitor's product.
ESS is correct about the O2 sensor location. It just requires additional tuning. The power gains are very real.
Another option is the CPI stepped headers, which have given me great results.