Jump to content
SAU Community

Recommended Posts

  • Replies 45
  • Created
  • Last Reply

Top Posters In This Topic

As much as i love my Trust setuo, i think the ball bearing Garret based HKS turbos are newer technology...but thats not to say the Trust turbos dont deliver the goods. Im still yet to see a std RB20 with a 2530 with the response/power of the TD06-20G.

...But, there is always the but, the 2530 makes almost the same power, with similar response all whilst using the std manifold etc etc. I doubt that the bolt on TD06-20G turbos would match a 2530, could be wrong and wait with interest to see the results of someone running one, but the fact that my TD06 uses the manifold and external wastegate i think it helps the overall performance.

From memory, R31nismoids GT30 equipped RB25 sees about 16psi at about 4,000rpm with a tuned length exhaust manifold and all support systems.

The RB25 is 25% larger in capacity than the RB20 so in theory it would see 16psi 25% later in the rev range at approximately 5,000rpm.

So I guess, if funds allowed and you wanted to take that route a GT30 might be a decent match for a no holds barred 9,000rpm RB20.

mine is with the 82 rear housing, with a .63 you'd be limiting power output of the turbo to around 500hp instead of 550/600... but IMO too laggy for the RB20.

you'd need to wring the guts out of it all day to get anywhere.

Oh, and my 24psi isnt on much later than around 4300-4400 where it goes to 8000rpm

just curious as to what the difference is bewteen a garret and HKS gt2530 are

ive seen heaps of hks version but only for gtr/silvia engines, and ive seen heaps of garret version only for rb series engine. can u show my a pic of a HKS gt2530 and NOT a garrett 2530. i just dont want to buy the wrong one

THX

what about a disco??? anyone heard of anyone using one on an rb20? i'm looking for an upgrade but i would like decent low end but an alright output.. i know you can't have the best of both worlds with out some gassy help but i was just curious if anyones tried this combo?!?!?!?!?!?!?!!?!? oh and if you don't know what a disco is its a garrett GT28RS.

Chris

Strange, but extremely well thought out.. The collector is the most important part of a turbo manifold, and positioning the wastegate like this enables a pefectly smooth collector design (ie no funny holes at strange angles that interfere with the gas flow path even when the wastegate is closed)

Ive seen several big HP drag cars with this mod - it works well.

Its perfect - The gasses going out the wastegate have a clear, unimpeded shot stright through the turbine housing.

 

Thats the problem. You dont want the air going straight out the turbine housing. You want the air to go thru the scroll of the housing, spin the turbine then out the exhaust. When there is a a certain amount of pressure in the housing you want the wastegate to open and bleed of airflow/pressure so that the turbine does not continue to accelerate.

Wastegates work on basically back pressure (pressure being theoretically equal against all surfaces) whilst the turbine relies on airflow which is directional...

Thats why my gut feeling is that is not the ideal orientation of the wastegate, but could be wrong...just curious to know why it was done this way?

"Thats the problem. You dont want the air goign straight out the turbine housing."

Well, you actually want part going through the housing and a small part going out the wastegate

"You want the air to go thru the scroll of the houisng, spin the turbine then out the exhaust. When there is a a certain amount of pressure in the housing you want the wastegate to open and bleed of airflow so that the turbine does not continue to accelerate."

Thats right - and to get any semblance of decent boost control, the gasses going through the wastegate need to do it easily. If the wastegate gasses have to turn 90 or 180 degrees to go through the wastegate, then they're going to take the easier path and go through the exhaust housing instead, which will cause overboost.

My above post explains why its been done this way. Im sure when Turbine replies he will back me up.

Sorry not convinced. Pressure isnt directional, and wastegates work to regulate pressure. Air is lazy and will piss out wherever/however it can, just look at what happens when you pop a gasket between the turbo flange and manifold.

I have seen this type of setup before, a few old school rotors/VLs etc, and dont have a problem with a wastegate being welded to the housing (very nice welding by the way), but i would have thought the angle at which it has been welded is not ideal.

Anyway, well will see:)

I guess we can respectfully disagree.

In a properly matached manifold, the gasses are traveling at at local speed of sound. They really dont want to change direction. Pressure may not be directional, but flow certainly is, and thats what we're trying to achieve. Flow..

Its a nice job thats for sure...

One thing - Wastegates work to regulate turbine speed, and boost pressure - not exhaust manifold pressure. The wastegate doesnt care what pressure is in the exhuast manifold - it only knows that it has to bleed off exhaust gasses when a certain amount of boost is present.

PS - I Love your Skyline :)

I guess we can respectfully disagree.  

LOL..yeh no problem:) This is a discussion forum:thumbsup:

In a properly matached manifold, the gasses are traveling at at local speed of sound. They really dont want to change direction. Pressure may not be directional, but flow certainly is, and thats what we're trying to achieve. Flow..

I know about Mach numbers, flow etc:) But i thought you would want flow thru the turbine first and foremost not the wastegate.

One thing - Wastegates work to regulate turbine speed, and boost pressure - not exhaust manifold pressure. The wastegate doesnt care what pressure is in the exhuast manifold - it only knows that it has to bleed off exhaust gasses when a certain amount of boost is present.

If there was not pressure in the exhaust manifold then there wouldnt be a pressure differential for the air to bleed off and control the turbine speed. The rest of it i agree with though.:)

Will wait and see i suppose...and thanks:)

"I know about Mach numbers, flow etc But i thought you would want flow thru the turbine first and foremost not the wastegate."

Cant disagree with that one :)

"If there was not pressure in the exhaust manifold then there wouldnt be a pressure differential for the air to bleed off and control the turbine speed."

I should clarify this - theres definitely pressure in the exhaust manifold, I just wanted to say that wastegates regulate intake manifold pressure, not exhaust manifold pressure..

Anyways, i think ive said enough :)

Cheers,

Matt

PS- nice to know people can still discuss things without resorting to a pissing contest :)

Sorry not convinced. Pressure isnt directional, and wastegates work to regulate pressure. Air is lazy and will piss out wherever/however it can, just look at what happens when you pop a gasket between the turbo flange and manifold.

I have seen this type of setup before, a few old school rotors/VLs etc, and dont have a problem with a wastegate being welded to the housing (very nice welding by the way), but i would have thought the angle at which it has been welded is not ideal.

Anyway, well will see:)

Roy, I know you like this mod, but air is not lazy, It's a powerfull mother of a thing wich if controlled properly can be used to develope big horsepower. The air at speed becomes like a solid and will not turn corners in a hurry at high speed.

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

    • From there, it is really just test and assemble. Plug the adapter cables from the unit into the back of the screen, then the other side to the car harness. Don't forget all the other plugs too! Run the cables behind the unit and screw it back into place (4 screws) and you should now have 3 cables to run from the top screen to the android unit. I ran them along the DS of the other AV units in the gap between their backets and the console, and used some corrugated tubing on the sharp edges of the bracket so the wires were safe. Plug the centre console and lower screen in temporarily and turn the car to ACC, the AV should fire up as normal. Hold the back button for 3 sec and Android should appear on the top screen. You need to set the input to Aux for audio (more on that later). I put the unit under the AC duct in the centre console, with the wifi antenna on top of the AC duct near the shifter, the bluetooth antenna on the AC duct under the centre console The GPS unit on top of the DS to AC duct; they all seem to work OK there are are out of the way. Neat cable routing is a pain. For the drive recorder I mounted it near the rear view mirror and run the cable in the headlining, across the a pillar and then down the inside of the a pillar seal to the DS lower dash. From there it goes across and to one USB input for the unit. The second USB input is attached to the ECUtec OBD dongle and the 3rd goes to the USB bulkhead connected I added in the centre console. This is how the centre console looks "tidied" up Note I didn't install the provided speaker, didn't use the 2.5mm IPod in line or the piggyback loom for the Ipod or change any DIP switches; they seem to only be required if you need to use the Ipod input rather than the AUX input. That's it, install done, I'll follow up with a separate post on how the unit works, but in summary it retains all factory functions and inputs (so I still use my phone to the car for calls), reverse still works like factory etc.
    • Place the new daughterboard in the case and mount it using the 3 small black rivets provided, and reconnect the 3 factory ribbon cables to the new board Then, use the 3 piggyback cables from the daughterboard into the factory board on top (there are stand offs in the case to keep them apart. and remember to reconnect the antenna and rear cover fan wires. 1 screw to hold the motherboard in place. Before closing the case, make a hole in the sticker covering a hole in the case and run the cable for the android unit into the plug there. The video forgot this step, so did I, so will you probably. Then redo the 4 screws on back, 2 each top and bottom, 3 each side and put the 2 brackets back on.....all ready to go and not that tricky really.      
    • Onto the android unit. You need to remove the top screen because there is a daughterboard to put inside the case. Each side vent pops out from clips; start at the bottom and carefully remove upwards (use a trim remover tool to avoid breaking anything). Then the lower screen and controls come out, 4 screws, a couple of clips (including 3 flimsy ones at the top) and 3 plugs on the rear. Then the upper screen, 4 screws and a bunch of plugs and she is out. From there, remove the mounting brackets (2 screws each), 4 screws on the rear, 2 screws top and bottom and 3 screws holding in the small plates on each side. When you remove the back cover (tight fit), watch out for the power cable for the fan, I removed it so I could put the back aside. The mainboard is held in by 1 screw in the middle, 1 aerial at the top and 3 ribbon cables. If you've ever done any laptop stuff the ribbon cables are OK to work with, just pop up the retainer and they slide out. If you are not familiar just grab a 12 year old from an iphone factory, they will know how it works The case should now look like this:
    • Switching the console was tricky. First there were 6 screws to remove, and also the little adapter loom and its screws had to come out. Also don't forget to remove the 2 screws holding the central locking receiver. Then there are 4 clips on either side....these were very tight in this case and needed careful persuading with a long flat screw driver....some force required but not enough to break them...this was probably the fiddliest part of the whole job. In my case I needed both the wiring loom and the central locking receiver module to swap across to the new one. That was it for the console, so "assembly is the reverse of disassembly"
    • But first....while I was there, I also swapped across the centre console box for the other style where the AV inputs don't intrude into the (very limited !) space.  Part# was 96926-4GA0A, 284H3-4GA0B, 284H3-4GA0A. (I've already swapped the top 12v socket for a USB bulkhead in this pic, it fit the hole without modification:) Comparison of the 2: Basically to do the console you need to remove the DS and PS side console trim (they slide up and back, held in by clips only) Then remove the back half of the console top trim with the cupholders, pops up, all clips again but be careful at the front as it is pretty flimsy. Then slide the shifter boot down, remove the spring clip, loose it forever somewhere in the car the pull the shift knob off. Remove the tiny plastic piece on DS near "P" and use something thin and long (most screwdrivers won't fit) to push down the interlock and put the shifter down in D for space. There is one screw at the front, then the shifter surround and ashtray lift up. There are 3 or 4 plugs underneath and it is off. Next is the rear cover of the centre console; you need to open the console lid, pop off the trim covering the lid hinge and undo the 2rd screw from the driver's side (the rest all need to come out later so you can do them all now and remove the lid) Then the rear cover unclips (6 clips), start at the top with a trim tool pulling backwards. Once it is off there are 2 screws facing rearwards to remove (need a short phillips for these) and you are done with the rear of the console. There are 4 plugs at the A/V box to unclip Then there are 2 screws at the front of the console, and 2 clips (pull up and back) and the console will come out.
×
×
  • Create New...