I have compounds on my 97 12v, I have stock hx35 with a 475. I had my 35 waist gate super tight from when it was my single. When I put the 475 on I could produce 70psi but I could tell drive pressure was high. I used a regulator and my air compressor to figure out how tight I wanted the waist gate. I set it so that it started to open and 25psi. It runs so much better, makes more power, has less drive pressure, spools faster, and does it at lower 60psi now.
So badly wanna call you guys up and tell you to send everything i need to make a 1000hp tow/daily monster. Unfortunately I'm not willing to sell my house to make it happen so I'll have to wait lol
Great info. Many times I have played with gates on guys compound turbo trucks and they are amazed after. I would say 50% of compound trucks have the gate set wrong.
From AUS here can you guys do this with your K27 compound kits compared to the other towing compound setups that are available for the 5.9 12V, id love to see the VE pump stuff compared to the P-Pump stuff too. I have a 12V VE with the stage 2 Power jet Nozzles, 4inch exhaust, k27. I do a mix of heavy towing and daily driving, I'm looking at possibly doing a compound setup with a cam as mines damaged. Not chasing more than 450ish hp as my little Toyota 80 diffs and a stock manualized 47re will hate me, thanks and keep rockin on!
I am actually kinda glad I havent been able to afford my parts yet, because I am getting invaluable info prom all these videos from PDD. I have been putting all the data together for optimizing the build on the 94. Can you guys put together a video that addresses matching intake configurations as well as post-turbo exhaust configurations and if it is advantageous to try and scavenge exhaust velocity or if it is a waste of time and better to just dump the exhaust asap. I am trying to figure out how to get the most multi-purpose out of this rig. I love power and kinda want the ability to do everything from hauling a nice big travel trailer to the baja and then unhook and have some real fun. I just don't want to have any doggy spots in performance because of poor planning.
You put out the electronic package to monitor what you are presenting to us... alls I have to go by are boost and drive gages... they both go to 80 from what I see when testing on that street in Mexico
Im very curious how egts and iats as well as how the size of the atmospheric charger would or could change if an inter-stage w/a intercooler was present. Textbook-wise this makes tons of sense. Why is inter-stage cooling seldom used in the diesel world? Because you can just inject water on a race truck? Not worth the gains and complexity on a street truck? Seems like it would be a killer idea on a tow monster setup. Id be curious to know more about that, and if that affects wastegate tuning. Im just doing research on diy-ing my own compound setup and trying to do as much math and figuring as possible and came across this video, which was extremely helpful. Sincerely, Happy PDD customer. Lol
Whoever said you cant make boost without a higher drive pressure obviously needs some educating. You added a butt load of energy to the air in the cylinder and I know an internal combustion engine isn't 100% efficient so that energy exits the exhaust leaving plenty to drive a turbo with a 1:1 ratio for most of the engine RPM.
Remember men- Nothing wrong with tuning for LESS than stock power The payout is a machine that lasts a lifetime. Rather than one that tingles your feels
Id love to see these guys get together with gale banks, i dont think gale would approve of the smoke these guys put out but he will 1000% love all the data and numbers these guys are gathering. Would love to see the outcome and hear some of gales recommendations
"How do you make more boost, but not make more power?" Easy. Don't add any more fuel. Lots of interesting stuff going on with compound turbos. Would be curious to see the lowest boost you can run and still hit ~850hp by 2500rpm. Anything above 'tuned wastegate' boost curve is obviously not productive. Could you start to open the wastegate a hair earlier, target ~5psi less peak boost, hit ~10psi less peak drive pressure, and end up with the same power?
I have an external gate that is pushing open with backpressure on my single turbo system, I have to put pressure on the dome to hold it closed until I want it to open, and I suspect it's leaking a lot before I get to my target boost.
So on a single what do you think makes more power 50psi gate closed drive rising to 70 or 42psi rising to 47 drive? Playing with drive pressure spring gates that was as good as I got so going back to an air assisted gate to try to get better control. My SOP meter seemed to indicate the tight gate made more peak but suffered with rpm while the lower drive was flatter and possibly at higher rpms surpassed the tight gate despite being less boost, much like your tuned twins. Oh yeah tell Todd there are internal gated s400 housings. 🙂