Correct, I cannot back this up without a compressor map. But you cannot back up your argument without a compressor map either.
In case of the bottom charger overspeeding why not put a bigger one on?
twin setup?
- Thread starter motohed
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Correct, I cannot back this up without a compressor map. But you cannot back up your argument without a compressor map either.
In case of the bottom charger overspeeding why not put a bigger one on?
Well then how do you plan to use a gate to put it in the efficiency island if it can't be done without a map? Do you have a map? I do
The math is very simple. Could you please show us how you crunch the numbers.
Simple problem: Both chargers in a compound setup are being run at 3:1 pressure ratios. Assuming 15psia for baro pressure what amount of boost would they be putting out?
no, the two turbos have to work together to have a 1:1 ratio. i guarantee that my large turbo is not small. it is a s480 with a 80mm inducer and a 110mm exducer ett comp wheel, and the turbine wheel is a 88/96mm.
please enlighten us. the rest of us are dumb and have built twins the wrong way according to you
No im not bashing anyones twins im sure they run fine, but are they as efficient as they could be??? If nobody ever questioned anything, there would be no advancement, hopefully someone will learn something from this thread and apply it to their truck.
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For those that would like to know
A bottom charger running at a 3:1 P/R will make 45 PSIA or 30 PSI of boost
15*3=45psia
Them a top charger reciving 45psia running at a 3:1 P/R will turn that into 135 PSIA or 120 PSI of boost
45*3=135
then
135-15=120
ANSWER: 120 pounds of boost
Most turbos are still in their efficiency range at 3:1 P/R
Most D-Max guys run around 2:1 P/R. Your turbos are barely working and are super forgiving at this level. Tuning to make 50 or 60 pounds is far from rocket science, it very easy and leaves a lot of room for error. Tuining a Cummings for 130 pounds or a C15 for 160 pounds if far more dificult because you are on the verge of breaking chit if you dont run your turbos at the same P/R
OK, the wifey is yelling at me, time to go to bed
A bottom charger running at a 3:1 P/R will make 45 PSIA or 30 PSI of boost
15*3=45psia
Them a top charger reciving 45psia running at a 3:1 P/R will turn that into 135 PSIA or 120 PSI of boost
45*3=135
then
135-15=120
ANSWER: 120 pounds of boost
Most turbos are still in their efficiency range at 3:1 P/R
Most D-Max guys run around 2:1 P/R. Your turbos are barely working and are super forgiving at this level. Tuning to make 50 or 60 pounds is far from rocket science, it very easy and leaves a lot of room for error. Tuining a Cummings for 130 pounds or a C15 for 160 pounds if far more dificult because you are on the verge of breaking chit if you dont run your turbos at the same P/R
OK, the wifey is yelling at me, time to go to bed
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fancy gating can help out if you have lots of free time on your hands (i dont). and no turbo charging isnt perfect and efficient as it can be, but most of the time it works
Ok DUDE i dont know what your agenda is but I DID NOT post here to BASH YOU. Dont take every thing so personal.
not at all. i was stating that i dont have alot of free time. no agenda here, just stating that to have everything just right, you will need alot of free time on you hands and alot more tuning. thats all! no bash, nothing personal
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balance the pressure ratios.........If you try and push the big turbo to do all the work, you're in for high drive pressure....unless my drive pressure gauge has been lying to me
