Jump to content
SAU Community

Recommended Posts

And didn't you lift a head or blow your motor?

Squeezing all that pressure into a tiny T3 flange, then releasing all that pressure after the restriction is counter intuitive. That's why as soon as people go to high mounts they pick up power but it's not so much the high mount it's more so the exhaust gasses be bleed off before the collector.

Boost control is subjective, and your 6tits probably doesn't have twin gates off it or the merge between both scrolls to the gate was poor.

If you ever have an exhaust pressure sensor or gauge on the collector you'll understand.

1 minute ago, Griffin said:

Is there any difference having wastegate on manifold at / before collector over the turbine housing?

Yep, you'll reduce exhaust back pressure, make more power, less things glowing on the hot side.

I did that only mod and with the same timing map, same boost, same turbo (except it was a BB centre this time round, same comp/turbine wheel) and made extra 20kW off the bat. 

4 hours ago, Dose Pipe Sutututu said:

And didn't you lift a head or blow your motor?

Squeezing all that pressure into a tiny T3 flange, then releasing all that pressure after the restriction is counter intuitive. That's why as soon as people go to high mounts they pick up power but it's not so much the high mount it's more so the exhaust gasses be bleed off before the collector.

Boost control is subjective, and your 6tits probably doesn't have twin gates off it or the merge between both scrolls to the gate was poor.

If you ever have an exhaust pressure sensor or gauge on the collector you'll understand.

Wouldn't the actual restriction be the actual turbine housing itself?
By my understanding of pressure, the pressure inside the manifold would not be altered depending on where the gate was, as long as it's between the head and the turbine wheel.

I had 1 gate in both setups, and a 45mm gate off the housing vs a 50mm gate off the 6boost. You can tell just by looking at it which gate is in the better spot for flow.

I agree with you, going external gate does free up power, once you start to really get the most out of any specific turbo. IWG's of any kinds (Even on EFR's!) seem to just not cut it once you really, really want to get the most out of a rear housing.


In this example though, the engine is likely to let go before the turbo or gate really even gets involved as a point of discussion

Here's a thought experiment.

Let's say that the exhaust gas needs to be split 50/50 between the gate and the turbine.  If the ext gate is on the turbine housing, then you are shoving double the amount of gas into the housing than if the gate was on the manifold somewhere.  Either way, we want the same 50% to make it all the way to the nozzle, but in the region between the flange and the housing mounted gate, the gas velocity must be double.  Pressure losses go up with the square of velocity.  So whatever frictional losses occur, they are doubled.  The exhaust gas is losing energy before it has even made it to the turbine.  It must therefore not be as good as if it was vented before the housing.

The difference might not be large, but it will be there.

The one big advantage of putting the gate on the housing is that it is easier to put it in a spot where the gas is definitely flowing towards the gate (because all the gas is flowing that way anyway) which makes it a little harder to f**k it up the way that people do when they put ext gate offtakes onto manifolds at bizarre angles.

  • Like 1

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now



  • Similar Content

  • Latest Posts

    • Maybe also really stiffly sprung track cars. Get the inside wheel up in a corner and all the fun stops. Also me sometimes (rarely) when I have to stand on the brake to convince the diff to drive the wheel that is still on the ground when I'm trying to diagonally get over severe driveway entrance, etc.
    • I feel like I'm missing something. You had an authorised installer come out and install a new alarm. Post install the car doesn't start, and you aren't getting the installer back to fix what they did wrong?
    • So either way it is gearbox out and look what is wrong?  I know about the input shaft bearing. Even before swap/new clutch the it sounded exactly like this: So is that inout shaft bearing or the other was installed backwards?  And can some please tell me the part number for that input shaft bearing? The gearbox is small box from R34 N/A and number is FS5W71C. Thank you  
    • I am yet to see anyone ever regret a quaife or helical. ...other than drifting/skidpan duties. I kind of want to upgrade my factory helical with a Quaife (but really it's not ultimately that different, and is a MASSIVE UNDERTAKING), that's how good the hype is about them, that I want to try them 'just to see'  
    • D2 and Ksport are essentially the same thing and basically just generic Taiwanese manufacture. Better than ChinaBay crap, but... not top shelf. Öhlins have got to be some of the best dampers around, so likely to be a good option. It's going to get to the point though where I suggest you buy from Oz. We have at least 2x excellent options here. If I were you though, I'd be talking to KW about doing something for the R33. There's bugger all difference between that and the 32. In GTR land, anyway.
×
×
  • Create New...