Tuning for high elevation?

greyford1979 · May 25, 2021

Going to be headed out to Colorado and Utah in a few months, and was just wondering if I would be able to get some tuning that would help in the mountains? Last year when I was in Colorado, I had a hell of a time getting the truck spooled since I had no load on it. Felt like when you blow a turbo boot and just smoked like crazy, then all of a sudden you had boost and took off like a bat outta hell. Made for some butt pucker moments when it did that coming up on a curve with a thousand foot drop and no guard rails lol. Currently running some Jelibuilt tunes and 1023 tunes here in Ohio, and truck runs great, in the mountains it was hating life lol. I can hit 40 psi no problem just getting on the expressway, out there 5-10 psi was a struggle. Can't really think of anything else to help with my current setup, besides going to a smaller exhaust housing, which I'm not gonna do for a yearly trip lol.

cjfarm111 · Jun 1, 2021

Great question. I live at higher elevations and would think tuning could be adjusted to help with less air at higher altitudes

Addicted4 · Jun 1, 2021

What is your setup currently? Injectors, turbo, hpop

PABowhunter · Jun 1, 2021

^What he said

My buddy just got back from a 6,000 mile trip out west from PA and noticed quite a difference at high elevations. Out here in PA we have plenty of air for power. He was running 238/80's and an SXE 366.

Have you talked with Brian or Dusty yet? I'd say whichever tuner is the most responsive and is willing to work with you. That's getting harder and harder though I feel like with the older the 7.3 platform gets.

greyford1979 · Jun 2, 2021

Yeah I haven't tried getting a hold of either one yet to see if anything could be done tuning wise. My current setup is 238/80 injectors, KC38R, Adrenaline hpop, complete Irate fuel system, intake with the blue Donaldson filter, and 5 inch straight exhaust. Also running a Sam Wyse trans with a DPC billet converter. Stock 3.73 gears and for tires a 295/70R18. I know I could benefit a bit from gearing, but for here in Ohio I don't need any reason to regear. Main thing that helped when I was in Colorado last year was turning overdrive off on the steep grades.

BS Hauler · Jun 21, 2021

You just have to keep the RPM's higher in high altitudes.

greyford1979 · Jun 21, 2021

BS Hauler said:
You just have to keep the RPM's higher in high altitudes.

Yeah that's what I ended up having to do by turning off OD in some areas. What did me in when was that I didn't even think about it till I was up over around 10,000 feet and slowed down in some curves and lost boost. When I got back on the throttle I thought my trans went and was slipping. Glanced over at my boost gauge and realized I screwed myself. After that first day I always turned OD off to help.

Dieselboy. · Sep 13, 2021

Altitude brings in a few issues with these old girls. There is a few MAPs we can tweak as far as the tuning side, but at the end of the day you are getting far less air in the mix to get a good efficient burn. Combine that with a much larger than stock injector/turbo and it makes it even worse.

The 38R based turbos in my opinion are the worst. If this is going to be a common thing towing at alititude I suggest changin up turbochargers. I have said this many times before that no dropin can do everything a properly sized T4 kit can do and still stand by it.
In my opinion the best drop in on the market is KCs 63mm charger as the factory exhaust housing/wheel will always be the restriction.
Ive done many live tuning sessions where you can see how much faster a T4 charger comes to life and still out shines it on the top end. Alot of people say that the T4 kits are only benficial when big power goals are set. And I disagree, the T4 charger gives you a much broader powerband and frees up usable RPM.

You can fudge timing tables to help things, but its margionally different, as lets face it. To get this side of things nailed down a said tuner would need to be live tuning in that exact situation. And lets face it, unless it was our own truck no one is gonna wanna pay for a session to go through and entire mountain pass/return trip.

You could try having one of the two guys mentioned play with the SOI tables and or manipulate the PW table. But sometimes subtracting fuel makes things worse.

euroford · Apr 19, 2022

I'm out here in CO and drive my truck extensively in the mountains, loaded and unloaded. Properly done, these things will fly up and over Vail pass. I'm running 250/100 injectors and a KC300x for my E99 with numerous supporting mods. My tuning was done by Dave back when he was still with Swamps, i pulled several datalogs for drives over Vail and Berthoud passes and for 1/4 mile runs at bandimere, he revised the tuning several times and I feel like its dialed. I really only run either the "hot street" for all of my driving and the race tune for the occasional fun pull. EGT's are really well managed so I have no reason to run the lower power tunes. I can sustain high speeds and 35psi over Vail pass, the EGTS pretty much hit a wall at about 1200 and climb no further.

I do also run a wastegate and a turbosmart boost controller. I think this helps, but is not something that has caught on.

So, good parts, good tuning and your good to go. As mentioned above, you do need to keep your RPM's up to keep the turbo lit in thin air. I think slightly easier for me as i'm a three pedal truck.