Maximum boost v. external wastegate spring
#28
This thread is a ******' trainwreck. I'm thinking about posting the same thing on ClubFagster just to see what sort of bullshit comes out for the lulz.
#29
I thought about stacking them, but they're too similar in OD.
The GOOD news is that i will be able to stack the 14psi and 7psi springs if i end up having enough fuel to want to crack 30psi.
#30
Ok, say you dont put the vac line on the wastegate at all. It will stay closed until the exhaust backpressure pushing on the diaphragm is greater than the spring pressure then it will start to crack open. It will spool like a normal car with a boost controller up to this point. After that point it will spool like a car without a mbc that is getting wastegate cracking. Now if you connect it like normal then the car will spool like normal until the the exhaust pressure + the boost pressure (coming through the mbc) is high enough to overcome the spring pressure. If the requested boost (from the mbc) is higher than that cracking exhaust pressure I mentioned earlier then it wont spool as hard. Eventually you'll make enough gas pressure that no matter what you set the mbc to the wastegate will be all the way open and you wont be able to make more boost.
So right now if it spools perfectly fine to 14 psi if you then set the mbc to like 24 psi then at the very least it would spool like normal to 14 psi and then get as high as 24 psi or till the exhaust pressure forces the wastegate all the way open.
So right now if it spools perfectly fine to 14 psi if you then set the mbc to like 24 psi then at the very least it would spool like normal to 14 psi and then get as high as 24 psi or till the exhaust pressure forces the wastegate all the way open.
#31
Ok, say you dont put the vac line on the wastegate at all. It will stay closed until the exhaust backpressure pushing on the diaphragm is greater than the spring pressure then it will start to crack open. It will spool like a normal car with a boost controller up to this point. After that point it will spool like a car without a mbc that is getting wastegate cracking. Now if you connect it like normal then the car will spool like normal until the the exhaust pressure + the boost pressure (coming through the mbc) is high enough to overcome the spring pressure. If the requested boost (from the mbc) is higher than that cracking exhaust pressure I mentioned earlier then it wont spool as hard. Eventually you'll make enough gas pressure that no matter what you set the mbc to the wastegate will be all the way open and you wont be able to make more boost.
So right now if it spools perfectly fine to 14 psi if you then set the mbc to like 24 psi then at the very least it would spool like normal to 14 psi and then get as high as 24 psi or till the exhaust pressure forces the wastegate all the way open.
So right now if it spools perfectly fine to 14 psi if you then set the mbc to like 24 psi then at the very least it would spool like normal to 14 psi and then get as high as 24 psi or till the exhaust pressure forces the wastegate all the way open.
Just stop posting..
OP,
Can't you also shim the original spring? I know it has to "seat" but doubt it would go anywhere if it didn't. The possible downside is boost creeping to death if current setup requires full range of motion on the valve.
#32
Ehhh... i could maybe look into shimming.
Stupid question: Shim goes under or on top of spring? I might be a little worried about seating, since i'm paranoid like that, but fueling would be more the issue than strength of motor if i DO run into creep issues.
To maybe hopefully illustrate what i'm talking about in terms of how the car responds... (and hopefully not to further confuse)
When i first hammer it in 2nd, you'll see the boost gauge hit 14psi pretty much immediately. You might be able to hear it, maybe not, but the car doesn't really "hit its stride" until maybe 1/4-1/2 a second after it's already achieved max pressure. It's not dependent on RPM, does it all the time. It'll kinda start moving as it spools up, but it just feels weird. Starts to move, hits full boost, wait for it.... SLAM. My Miata doesn't do this. (But of course, it's a baby dick motor with a baby dick turbo on the Miata.)
Stupid question: Shim goes under or on top of spring? I might be a little worried about seating, since i'm paranoid like that, but fueling would be more the issue than strength of motor if i DO run into creep issues.
To maybe hopefully illustrate what i'm talking about in terms of how the car responds... (and hopefully not to further confuse)
When i first hammer it in 2nd, you'll see the boost gauge hit 14psi pretty much immediately. You might be able to hear it, maybe not, but the car doesn't really "hit its stride" until maybe 1/4-1/2 a second after it's already achieved max pressure. It's not dependent on RPM, does it all the time. It'll kinda start moving as it spools up, but it just feels weird. Starts to move, hits full boost, wait for it.... SLAM. My Miata doesn't do this. (But of course, it's a baby dick motor with a baby dick turbo on the Miata.)
#37
Ehhhh.... maybe? If i go with the South Bend, i've driven that one and it's not a ton more pedal effort.
On the flip side, my clutch already never felt stock, but i have no idea what was in it. PO said it was stock, but i don't believe him.
But i've got the **** here to boot 25-30psi through this thing now, and there's no way i'm NOT doing that.
On the flip side, my clutch already never felt stock, but i have no idea what was in it. PO said it was stock, but i don't believe him.
But i've got the **** here to boot 25-30psi through this thing now, and there's no way i'm NOT doing that.
#39
Ehhhh.... maybe? If i go with the South Bend, i've driven that one and it's not a ton more pedal effort.
On the flip side, my clutch already never felt stock, but i have no idea what was in it. PO said it was stock, but i don't believe him.
But i've got the **** here to boot 25-30psi through this thing now, and there's no way i'm NOT doing that.
On the flip side, my clutch already never felt stock, but i have no idea what was in it. PO said it was stock, but i don't believe him.
But i've got the **** here to boot 25-30psi through this thing now, and there's no way i'm NOT doing that.
I fully support this statement