So, I've been running MS for a while now on a turbo 420a with a small 16g, stock cams, 2.0 displacement, trying to get it tuned in.

I noticed cruise speeds are way rich, like 12.8 or so. I've been trying to fix it with auto tuning and making some manual changes, and what I've just now realized is that I'm actually really close to having the AFR match the target AFR of the fuel trim cell I'm cruising in.

The problem is that when I'm in 5th gear cruising I'm at maybe 2200rpm? (Hard to tell actual speed since my speedo is unhooked right now)... anyway, in 5th gear, low throttle, cruise, I'm at like 120% engine load, which equates to about 120kpa, or as some would say "3 psi".

So, my AFR target table is starting to richen things up for safety/knock reasons, but I'm wasting fuel in the process.

So, is this typical to be making boost at cruise on a 420A?

Depends on way too many variables for anyone to answer you. Depends on turbine & compressor, piston compression ratio, can profile, throttle position at that point, etc.

---

2012 2500HD LML

I did not ask "what should my kpa be at cruise" and then not provide any details. I provided most of the details you mentioned, and I simply asked for some boosted 420a folks out there to let me know what the cruise is like on their turbo setups so I could possibly get an idea if what I'm seeing is typical.

I'm glad though that you are so eager to shoot down my question. Your amazingly quick response time is only outweighed by your lack of helpfulness.

---

2012 2500HD LML

I found the answer to my question elsewhere. You can close or delete or lock the thread if you'd like, but please keep in mind that a forum is meant for discussion, which is what I was attempting to start on the topic of cruise vacuum. Though this forum is probably not as happening as it once was, there are still people using this platform to make good power and have a good time. The 2gnt is a starter car these days, so some starter / newbie forum posts are to be expected. I'm sure it gets really old having to flog posts all the time that are utterly ignorant, but please try to understand when a post is not 100% perfect it does not come from a place of disrespect to the forum or its members.

It may seem like I'm overreacting to your first post, but re-read it and consider that it is not actually a request for additional information, it seems it was intended to point out the shortcomings of the OP, rather than addressing the question with an eye to help. Most of your responses to my posts have been of this same nature, and I see it with posts from other users as well.

I know the work you do is thankless and for the good of the community, but I think if this 2gnt community is going to survive the more senior members will have to help the newbies out, sometimes from day 1 of becoming a car enthusiast.