Hello,
Like the original poster, I too, am a novice to tuning. In terms of the stratified rev limiter, I like that fast (dn dn dn dn dn, excuse my feeble attempt at computer exhaust sounds) exhaust note. From reviewing several maps, and reading tons of info, I realize that the FiST looses boost and overall HP around 6000 RPMs. Ideally, I would like to set the RL at 5500 RPMs, but I wanted to hear all of your thoughts.
Thanks!
- JR
They can probably set the rev limiter to whatever you want for a little extra fee. However, there is no reason to set it lower than is necessary. If you want to shift at 5500, shift at 5500. The rev limiter is just a fail-safe to protect the engine. Also, just because the boost PSI or HP drop off a bit at 5500, doesn't mean that you should necessarily shift then if you are looking to maximize acceleration. When you shift up, you lose mechanical advantage and go back down the powerband a bit, so for most cars you are generally best going close to redline to maximize acceleration.
As for the stratified tune in general, I just got it a week or so ago, so too soon to judge for sure, but definitely has more pop than the OTS tune. The difference is most noticeable down low and in the middle of the rev range. The throttle mapping is more aggressive as well, so I find it really wants to jump off the line. I haven't taken it on the highway much, but my sense is that it tends to jump into boost more readily just cruising down the road (e.g. going up a small hill) at higher speeds. Again, I've only had a brief time with it, but I'll be curious to see if it affects highway MPGs. My MPGs so far have been lower than with the Cobb OTS, but I think that's cause it just makes you want to hoon it so much! Definitely worth the price for the fun factor.
As for safety, it's a lot of boost to be putting through that little turbo, but I get less knock than on the Cobb tune. Might be different for Stage 1 though as the stock intercooler is pretty prone to heat soak, and that high level of boost is not helping matters. I haven't heard about any failures related to a strat tune, but probably too soon to tell what the long-term implications are. There's always a risk when tuning/modding.