I was curious what everyone was seeing for boost on their compound setups at higher elevations. I have an lbz with a built motor, heads are reworked with bigger valves, s483 over Danville 4094, 100 overs, dual fuelers, etc. I'm over 7000 feet elevation and I'm seeing about 50-55psi turned all the way up in 5th gear. Never had this setup before so I wasn't sure if that boost level seemed right for the elevation/setup.
Twin turbo boost levels at higher elevation
- Thread starter boosted4life
- Start date
Your build sounds alot like what im going after, how does that setup do towing?
55psi is what most guys run at around here at 780'.
55psi is what most guys run at around here at 780'.
I haven't towed with it yet but I imagine it would do great, it comes on the big charger quickly, I was actually surprised with this elevation how quick it lights.
What is the big turbo making OP?
i make a total boost of 55psi at 7k feet with the big turbo pushing 23psi of that.
i make a total boost of 55psi at 7k feet with the big turbo pushing 23psi of that.
My old truck ran the MPI twin kit gated with the stock vvt. I drove it from the eastcoast around the Midwest and out to the westcoast. The truck ran the same no matter were I was boost stayed the same max and spooled fast.
Have you ran the pressure numbers for your elevation? What's your pressure ratios? At roughly 6500' with my old 67/88 combo and 60% injectors I could spike to 75psi in fifth gear with a loose atmosphere housing. Averaged 65-70psi.
Do you have a gauge on the 83? Need to know what it's making to see how well the setup is working.
Sounds like the waste gate could be adjusted with you fueling that setup with 100 overs and duals it damn sure should be making more than 55 lbs. I would suspect around 70lbs once dialed in. My 66/80 would make 55lbs on stock cp3.
we can only offer so much help without knowing what we are asking for in the bold. if you dont have a gauge there, i highly suggest you put one in UNLESS your tuner is certain they can dial boost in correctly without one (very unlikely though). the vanes are like a gate on a fixed vane turbo. if the tune has them opening up too far, your 483 is building alot of your boost and the 4094 isnt doing much. in the vis versa situation, you can overdrive the 4094, get a lot of drive pressure and the 483 will hardly be moving air. So you can see how needing to know the pressure between the two turbos is important in a case like this. It can also tell you the pressure ratios Dustin asked for with a little math.
I don't have one in there yet, I just got the truck together, but I do have a guage ordered and can post up again soon. Thanks everyone
I ran some numbers and I get about 26 psi on my big turbo and 55psi total. Egts also are high 1750-1800 in 5th gear wot
what do you mean "you ran some numbers"? is the 26psi what you saw on a gauge or did you somehow mathematically figure it out (dont see how that can be done)
Kyle I had no idea you made this much boost. My setup peaks around 75psi and I thought I was pushing it.
It is crazy how the different trucks and combos produce different numbers. Even with triples I barely saw 80psi on boost and when I was twinned with this exact combo I saw 65-68psi iirc.