• The site migration is complete! Hopefully everything transferred properly from the multiple decades old software we were using before. If you notice any issues please let me know, thanks! Also, I'm still working on things like chatbox, etc so hopefully those will be working in the next week or two.

Pulsing the turbocharger...

J

jbunla

New member
with this setup:






I do not own this or the pics as it was sent to a member on our fiero board. I was curious why I have never seen anyone look into the technology as another feasible solution to turbocharging.
 




SgtMarshal said:
can you be more specific? not sure what you are asking
Click to expand...

It seems that this setup is running a turbocharger with a split hotside (divided housing) and according to my source a very large turbine housing and wheel. The engine still uses the stock converter which flashes around 2200-2400rpms. The point is I have not seen anyone running setup like this that pulse the turbine efficiently for a street car. So wanted to hear if anyone has seen a working setup on these engines are what are there thoughts

Turbocharged400SBC said:
That's just a funky dual wastegate setup. Usually when yer wg is undersized for the lower boost settings (high bypass/reducing drive pressure)
Click to expand...

Actually these are two functional waste gates used to control each bank of the turbine (housing)


It is actually a 88 beretta GTU, with a 3800, not sure what type or version, but I am told it maybe a series3, getting a custom specific camshaft (no one knows much about the car...I am still digging)
 
jbunla said:
It seems that this setup is running a turbocharger with a split hotside (divided housing) and according to my source a very large turbine housing and wheel. The engine still uses the stock converter which flashes around 2200-2400rpms. The point is I have not seen anyone running setup like this that pulse the turbine efficiently for a street car. So wanted to hear if anyone has seen a working setup on these engines are what are there thoughts



Actually these are two functional waste gates used to control each bank of the turbine (housing)


It is actually a 88 beretta GTU, with a 3800, not sure what type or version, but I am told it maybe a series3, getting a custom specific camshaft (no one knows much about the car...I am still digging)
Click to expand...
I still have a ton of gtu/indy beretta stuff.
 
Ok got more info:







3800 series III twin-scroll (divided housing) turbocharger; the pulses are divided by the sequential firing order. Turbine is a modded p-trim and 58mm or 59mm compressor wheel. The housing is a huge one at 1.09 a/r. No one seems to be running this alternate style of pulse turbocharging in the community, I will start looking at the merit for my fiero 3800 turbo
 


Its just a twin scroll turbo I don't get what this "pulsing" is. Evo guys have been using twin scroll turbos for ages.

Obviously since its divided housings you can setup separate waste gates. I still don't see how using different WG pressure would matter. It would vent to whatever the lower pressure is and defeat the purpose of the higher pressure waste gate so both would have to use same pressure WG springs.

Edit. Does look like a fvck ton of fun in a light car! Wonder what it weighs. 2800#s is the goal for my caged gutted GP. Once engine trans and turbo junk is finished.
 
ImNowTylerTibbets said:
Its just a twin scroll turbo I don't get what this "pulsing" is. Evo guys have been using twin scroll turbos for ages.

Obviously since its divided housings you can setup separate waste gates. I still don't see how using different WG pressure would matter. It would vent to whatever the lower pressure is and defeat the purpose of the higher pressure waste gate so both would have to use same pressure WG springs.

Edit. Does look like a fvck ton of fun in a light car! Wonder what it weighs. 2800#s is the goal for my caged gutted GP. Once engine trans and turbo junk is finished.
Click to expand...

lol "its just a twin-scroll turbo" easier said than done:D

Apparently there are two main ways to apply turbocharging principles. One is constant pressure, while the other is pulse turbocharging. I don't think I said using different wg pressure?!? Anyways the main point is for street cars to use a huge turbo, this method appears to make transient throttle more responsive when using a large compressor and also flattens the power curve (street car), another benefit is keeping the converter (if you are auto) at a lower stall speed. To my understanding the car weighs in at around 2800lbs also; I can't wait to do this to my fiero!
 
Y'all are doing it wrong.
Equal length primaries with consistent cross sectional area at the merge into each scroll.
medusa3.jpg
 
Turbocharged400sbc said:
Y'all are doing it wrong.
Equal length primaries with consistent cross sectional area at the merge into each scroll.
Click to expand...

The jury is still out on equal length headers, especially for a street car; however I can entertain the idea when using a divided housing. A street car needs a lower boost threshold this will be assuming said car can make use of boost in the low rpms range
 


ImNowTylerTibbets said:
how is this not more complicated then necessary. Need to spool a bigger turbo use a 2 step......
Click to expand...

This may or may not be, if you can afford a divided housing...and an extra WG (not really necessary, just have to incorporate a specific kind of plumbing to WG)...so really just the housing and I mentioned "STREET" and "ALTERNATIVE" meaning not what every tom, dick and harry may be doing.
Plus, this has nothing to do with launch control, it is a type of turbocharging application...but I get your point though
 
jdredd said:
Looks like a lot of work for what?

Just buy right sized good turbo and call it a day....
Click to expand...

hahahahaha seems no one is listening...is this just status quo? this is a different way to turbocharge, how is this difficult to understand? Is like telling me to go get a RWD when asking how to make a fwd platform faster...
99.9% of you use the constant pressure setup, it is wonderful but that is just one way?!!?

No one has shown me how getting a divided housing is too much work? or is been innovative dead?
 
  • Pulse type turbocharger:
In pulse type turbocharger, the exhaust gas directly enters the turbine side and drives the turbine with the exhaust gas energy. The connection from the exhaust side of an engine is directly connected to the turbine side of a turbo charger. The pipe connections from the exhaust gas towards the turbine side are generally small in length and exhaust grouping is provided to prevent the blowback of gases from one cylinder to another.

  • Constant pressure type turbocharger:
In constant pressure type turbocharger, the exhaust gases gets collected in a single exhaust gas reservoir, where the pressure is maintained constant so as to avoid any fluctuation in the exhaust gas energy pressure. The exhaust gas is introduced to the turbine side after maintaining the pressure inside the cylinder.




meh, turbo spools you go all that matters
 
You must log in or register to reply here.
Back
Top