Jump to content
SAU Community

Recommended Posts

Hey all,

I am looking at putting an external wastegate on the standard rb25det exhaust manifold,

-just wondering if anyone could tell me how they have gone about doing it.

-e.g. welder type used, method of welding, position on the manifold.

Also Pictures would be greatly appreciated.

-i am doing this because i have a bigger turbo.

-i am a student and cant afford to spend $500+ on a nice shiny exhaust manifold.

-i have searched(for 5hrs), and found very little information on the subject.

thanks, Joe.

If the turbo needs the gate then here's an example of putting it onto the standard manifold. Remember its best to put it in a (manifold < gate, turbo) kind of shape so that the gas's can be split evenly when needed, if you put the gate straight up or off to the side etc the flow distribution would be sh*t.

There is some information on the turbosmart website about it all if you look into it. Get a professional to do this as its not an easy job!

Here's the pic link i uploaded for you and one of the boost line. Boost control with the eboost2/gate is simply awsome :P

http://img81.imageshack.us/img81/651/manigateturbose1.jpg

http://img182.imageshack.us/my.php?image=300rwhpwi5.jpg

There isnt a lot of info because its nothing short of a mission, and the rooting around almost offsets the costs in most cases.

I can only remember in the last 4 years seeing pics of 3 or 4 such setups and they were a while ago when turbo range was not what it was today.

So, you have 3 options

1) Somehow mod the stock manifold nead the collector area

2) Have a spacer plate made up with an outlet that leads to the external gate, and have it run off that.

3) Graft/weld the gate onto the exhaust housing of the turbo

1st, is as i said.

2nd isnt that much difficult than #1, but it will cost you a few hundred at the least as there is a bit of measuring to be done.

3rd can be easily stuffed up if the welder isnt as good as they say they are, and will cost you more in the long run if they stuff it up as it will root the housing and/or gate.

Just a few quick questions though.

Why not use an internally gated turbo to begin with? They will rattle off pretty much upto 300rwkw...

For a poor student, im guessing thats miles out of your league to begin with???

Being you'd need the 10k worth of supporting modifications

Now, because i know people who have had similar ideas too yours...

Sell the turbo, sell the gate.

Purchase an int gated/bolt-on turbo and pocket the change for your school books or a set of injectors/ecu/afm/clutch/diff and the countless other things you need :P

you can buy an adapter that goes between the manifold and turbo and that the wastegate bolts upto there bout 200-250 i think, but thats what it will cost you too get it welded in as the cast iron is hard to well to and can break really easily

you can buy an adapter that goes between the manifold and turbo and that the wastegate bolts upto there bout 200-250 i think, but thats what it will cost you too get it welded in as the cast iron is hard to well to and can break really easily

thanks sinistagtst, an adapter will not work for me as my turbo is allready about 20mm from the chassis. And my dad will be welding it, he is very experienced welder but has not had much experience welding cast, and told me of the same cracking problem that could occur.

does anyone know if it would be possible to drill a hole in the manifold and tap it to accept a thread so welding wouldn't be necessary?

Keep the information coming people, it is extremely helpful.

its just a shit fragile metal........basically apparently the matal has to be heated up for ages and cant be cooled too quickly. even then it can still crack. i mean give it a go and if it doesnt work standard manifolds are cheap as esp on ebay. like 10bucks....

You must weld it. The heat that its all going to see wont like being tapped/thread.

Your dad it totally correct. Hence your going to be paying $$$ to someone as i wouldnt risk your dad if he isnt expirienced in that area.

It will cost you more money in the end

What turbo as you using?

What motor?

strongly agree, why re-invent the wheel and go through the same heartaches as someone else has. buy an already built manifold. if you cant afford the manifold then how do you plan to afford all the other ancillaries to run the new larger turbo, not even thinking about the tune at this stage

thanks R31Nismoid,

the turbo is internally gated(and apparently bolt on- its internal gate was said to be set at 12psi), and on the car atm, and i do have the supporting mods.

My engine is an rb30det and produces too much exhaust gas for the small internal wastegate...therefore boosting up to whatever it wants, e.g. ~20psi at 3000rpm, currently i have the internal wastegate partially open so that it does not boost as quick. But i still cant rev it past 3800rpm as it leans out over that.

-The company i bought the turbo from have kindly sent me an external gate.

-If i want to be able to control boost in the short term this is my only option.

-In the long term i will buy a custom stainless exhaust manifold.

modifying the turbine housing would be no advantage as it is cast iron as well and only further complicates matters, including the possibility of ruining the turbine housing.

i have allready ground out the internal wastegate for maximum flow, it helped but not enough.

im not sure its a good idea to hack an exgate onto it.

you are really band-aiding the problem with another hack solution.

if the gate is too small then fitting an ex gate just moves that to somewhere else, it wont actually fix it. if this is what you are seeing the perhaps the rear a/r housing is too small for the engine?

I had this same prob not long ago. I ended up making a T3 to T3 adaptor with the gate in it as already mentioned, but if you have no room thats not really an option.

Just take it to a workshop and ask them to do it, you might pay like max $100, and then its done properly.

I found this too which might be a good indication as to if you can DIY:

http://www.lincolnelectric.com/knowledge/a...ironpreheat.asp

Your dad it totally correct. Hence your going to be paying $$$ to someone as i wouldnt risk your dad if he isnt expirienced in that area.

Dad is free, the cost of someone else welding it would most probably cover buying another second hand manifold. And yes im going to be asking some people i know about it, which is also why i'm posting on this forum.

thanks again.

im not sure its a good idea to hack an exgate onto it.

you are really band-aiding the problem with another hack solution.

if the gate is too small then fitting an ex gate just moves that to somewhere else, it wont actually fix it. if this is what you are seeing the perhaps the rear a/r housing is too small for the engine?

thanks paul, yes it is a bandaid job, and yes in the future im sure a bigger turbo will go on, when money allows, for the time i just want to be able to control the boost.

http://www.turbosmart.com.au/index.php?s=f...load&id=112

This shows the flow thats best for the wastegate (bottom of page 3, top of page 4)

If you can't get enough flow out of the wastegate flap then blocking up the wastegate flap and fitting an external gate will fix the problem aslong as the gate is big enough of course :P

thanks R31Nismoid,

the turbo is internally gated(and apparently bolt on- its internal gate was said to be set at 12psi), and on the car atm, and i do have the supporting mods.

My engine is an rb30det and produces too much exhaust gas for the small internal wastegate...therefore boosting up to whatever it wants, e.g. ~20psi at 3000rpm, currently i have the internal wastegate partially open so that it does not boost as quick. But i still cant rev it past 3800rpm as it leans out over that.

-The company i bought the turbo from have kindly sent me an external gate.

-If i want to be able to control boost in the short term this is my only option.

-In the long term i will buy a custom stainless exhaust manifold.

modifying the turbine housing would be no advantage as it is cast iron as well and only further complicates matters, including the possibility of ruining the turbine housing.

i have allready ground out the internal wastegate for maximum flow, it helped but not enough.

What turbo/where is it from?

Im interested as with guys playing with 30DET's now and the new Garrett IW's ... its interesting :P

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

    • Next on the to-do list was an oil and filter change. Nothing exciting to add here except the oil filter is in a really stupid place (facing the engine mount/subframe/steering rack). GReddy do a relocation kit which puts it towards the gearbox, I would have preferred towards the front but there's obviously a lot more stuff there. Something I'll have to look at for the next service perhaps. First time using Valvoline oil, although I can't see it being any different to most other brands Nice... The oil filter location... At least the subframe wont rust any time soon I picked up a genuine fuel filter, this is part of the fuel pump assembly inside the fuel tank. Access can be found underneath the rear seat, you'll see this triangular cover Remove the 3x plastic 10mm nuts and lift the cover up, pushing the rubber grommet through The yellow fuel line clips push out in opposite directions, remove these completely. The two moulded fuel lines can now pull upwards to disconnect, along with the wire electrical plug. There's 8x 8mm bolts that secure the black retaining ring. The fuel pump assembly is now ready to lift out. Be mindful of the fuel hose on the side, the hose clamp on mine was catching the hose preventing it from lifting up The fuel pump/filter has an upper and lower section held on by 4 pressure clips. These did take a little bit of force, it sounded like the plastic tabs were going to break but they didn't (don't worry!) The lower section helps mount the fuel pump, there's a circular rubber gasket/grommet/seal thing on the bottom where the sock is. Undo the hose clip on the short fuel hose on the side to disconnect it from the 3 way distribution pipe to be able to lift the upper half away. Don't forget to unplug the fuel pump too! There's a few rubber O rings that will need transferring to the new filter housing, I show these in the video at the bottom of this write up. Reassembly is the reverse Here's a photo of the new filter installed, you'll be able to see where the tabs are more clearing against the yellow OEM plastic Once the assembly is re-installed, I turned the engine over a few times to help build up fuel pressure. I did panic when the car stopped turning over but I could hear the fuel pump making a noise. It eventually started and has been fine since. Found my 'lucky' coin underneath the rear seat too The Youtube video can be seen here: https://www.youtube.com/watch?v=uLJ65pmQt44&t=6s
    • It was picked up on the MOT/Inspection that the offside front wheel bearing had excessive play along with the ball joint. It made sense to do both sides so I sourced a pair of spare IS200 hubs to do the swap. Unfortunately I don't have any photos of the strip down but here's a quick run down. On the back of the hub is a large circular dust cover, using a flat head screw driver and a mallet I prised it off. Underneath will reveal a 32mm hub nut (impact gun recommended). With the hub nut removed the ABS ring can be removed (I ended up using a magnetic pick up tool to help). Next up is to remove the stub axle, this was a little trickier due to limited tools. I tried a 3 leg puller but the gap between the hub and stub axle wasn't enough for the legs to get in and under. Next option was a lump hammer and someone pulling the stub axle at the same time. After a few heavy hits it released. The lower bearing race had seized itself onto the stub axle, which was fine because I was replacing them anyway. With the upper bearing race removed and the grease cleaned off they looked like this The left one looked pristine inside but gave us the most trouble. The right one had some surface rust but came apart in a single hit, figure that out?! I got a local garage to press the new wheel bearings in, reassemble was the opposite and didn't take long at all. Removing the hub itself was simple. Starting with removing the brake caliper, 2x 14mm bolts for the caliper slider and 2x 19mm? for the carrier > hub bolts. I used a cable tie to secure the caliper to the upper arm so it was out of the way, there's a 10mm bolt securing the ABS sensor on. With the brake disc removed from the hub next are the three castle nuts for the upper and lower ball joints and track rod end. Two of these had their own R clip and one split pin. A few hits with the hammer and they're released (I left the castle nuts on by a couple of turns), the track rod ends gave me the most grief and I may have nipped the boots (oops). Fitting is the reversal and is very quick and easy to do. The lower ball joints are held onto the hub by 2x 17mm bolts. The castle nut did increase in socket size to 22mm from memory (this may vary from supplier) The two front tyres weren't in great condition, so I had those replaced with some budget tyres for the time being. I'll be replacing the wheels and tyres in the future, this was to get me on the road without the worry of the police hassling me.
    • Yep, the closest base tune available was for the GTT, I went with that and made all the logical changes I could find to convert it to Naturally Aspirated. It will rev fine in Neutral to redline but it will be cutting nearly 50% fuel the whole way.  If I let it tune the fuel map to start with that much less fuel it wont run right and has a hard time applying corrections.  These 50% cuts are with a fuel map already about half of what the GTT tune had.  I was having a whole lot of bogging when applying any throttle but seem to have fixed that for no load situations with very aggressive transient throttle settings. I made the corrections to my injectors with data I found for them online, FBCJC100 flowing 306cc.  I'll have to look to see if I can find the Cam section. I have the Bosch 4.9 from Haltech. My manifold pressure when watching it live is always in -5.9 psi/inHg
    • Hi My Tokico BM50 Brake master cylinder has a leak from the hole between the two outlets (M10x1) for brake pipes, I have attached a photo. Can anyone tell me what that hole is and what has failed to allow brake fluid to escape from it, I have looked on line and asked questions on UK forums but can not find the answer, if anyone can enlighten me I would be most grateful.
    • It will be a software setting. I don't believe many on here ever used AEM. And they're now a discontinued product,that's really hard to find any easy answers on. If it were Link or Haltech, someone would be able to just send you a ECU file though.
×
×
  • Create New...