I agree, keep the info coming here. I am learning something!!
So you have all the data. I have a BV43 housing(BV43A center section), Passat 2.0 exhaust manifold.
I have very little data, just some personal experience screwing around with junkyard garbage with zero budget.
IIRC the BV43 is already a bit of a step above the 1749v family, still pretty small but better.
you should be able to make an adapter plate from that manifold to basically anything with relative ease
So you'd recommend a newer Wastegated turbo over a vnt? If im understanding correctly. Or is there another type i don't know of?
This is all interesting to me because most people push for the vnt17, or a bigger turbo (gtb whatevers) i dont understand all the numbers and letters that usually follow on them things.
nope, the td04 I recommended up there is '90s tech
its just physically a better size match for the flow requirements and happens to be very available right now as those particular saabs are all meeting the crusher
gtb is newer generation and the vane mech is way different, gtc and gtd are even newer revisions
iirc the numbers are generally something like this
2060 = "20" turbine family, though gt 15, 17, 18, 20, 22, and 25 are all pretty wishy washy in that the shaft dimensions are all the same so you can do a lot of mixing and matching, some gt17 turbines are larger than some gt20 pieces so its kinda a more meaningless number
then the 60 is compressor wheel exducer diameter which is at least a concrete measurement
the letters are a mess as well with some turbos not fitting into the conventional lettering schemes
I'm far from anyone you should listen to on those sorts of things, I just throw the numbers into google (or ebay) to get dimensions of the compressor and turbine wheels and to a lesser extent the factory application power output, then base my choice on that.
turbos are something that you can do a lot of math on sizing, but if your budget doesn't allow for picking and choosing brand new $1500 turbos then there isn't much point to the math
you can get extremely good results by just choosing a factory application turbo (so the wheels are well matched to each other size-wise) for a power output in the range of what you want to make
though you should keep in mind expected duty cycle of the engines, something like a generator, tractor, or pump motor is going to have a turbo that's sized to be the most efficient at near 100% rated output.
Something on a car will be sized much smaller as they're only looking to make a small percentage of peak output for any length of time, so they can run it way too hard completely wrung out on the top end and it doesn't matter to them that you're basically just throwing fuel at forcing exhaust through it because its such a small percentage of the operation time. They want zero lag. They want easy emissions tuning.
basically, something on a 170hp genset is going to have a compressor inducer around say 50-55mm whereas a 170hp car motor can be well under a 40mm inducer
you're running your engine at a much higher duty cycle than it was being run in the car it came out of (and the car that your turbo came from) so you're running the turbo a lot harder than it'd be most efficient doing, throwing fuel at moving air
look at it like you're asking the engine (injecting fuel) to make 150hp, but because of the high exhaust pressure relative to the intake pressure you're only getting 100hp out of the crankshaft to actually pull the vehicle up that hill.