How to port the wastegate?
 

Just bought new turbos from Mazda, I am going to ceramic coat them but was thinking I should port the wastegate first. I know that porting will help control boost creep, but are there downsides? And how much and where do I take the material off.. Any pictures or tips would be appreciated.

Dan

Get a can of spray paint. spray the flapper door and surrounding area. Open the door and take a look at the wastegate. you will be able to see how much material you can grind away. there is a lot of room to grind and grind and grind and grind.

Port the wastegates first.

Wear safety glasses.

thesaint

Are there 2 waste gates for the turbos, or is that other door for spinning up the second turbo.. If there are 2 do you port them both?

Dan

?

still waiting for the reply saint

Id really like to get the new turbos i this weekend, as so far its nice here in WI... and I'd really like to port the waste gate(s) before I have to do this mod as a separate project.

Any input would be appreciated..

Dan

OK, well I looked in the book, and have decided that it would be a huge mistake to port the turbo-precontrol door (this is the one that is on the bottom of the housing covered by its own plate. I think many people mistakenly port this, and think it is the waste-gate, but its function appears to be to start the second turbo spinning, just before the turbo control door opens exhaust to the secondary turbo.

It is supposed to allow 5% flow to the secondary to start it spinning; I would imagine that if you ported this, it would wreck your transition.

You would serve yourself much better by porting around the larger door (in the exhaust manifold) to increase flow to the second turbo when the door is open.. But I would imagine that this would have the potential to imbalance the flow between the turbos. There is only one way for the exhaust to bypass the turbo, and that is through the wategate, which is inside of the exhaust housing on the primary turbo (you have to take the 3 sections apart to get to it)..


Dan

There aren't two wastegates. The wastegate is located in the cast turbine housing on the primary turbo.

Just make the damn things non-sequential. Get rid of all that rat's nest bullshit and two of the three actuators near the turbos. Makes things a helluva lot simpler.

Im just about to get a FMIC, intake and a MP, and I am planning to do the wastegate porting and port at the same time.

Is it hard to remove the turbos? What will I have to take away to get them off?

When you port the wastegate- you do the hole in the primary exhaust housing-the one looking at you when you look at the engine bay. The most you should have it ported is 1.24. I suggest you go at about 1.21 for sequential use. BTW do not DIY. Bring it to a machine shop-if you mess it up a little, there goes your housing!

When you port the wastegate- you do the hole in the primary exhaust housing-the one looking at you when you look at the engine bay. The most you should have it ported is 1.24. I suggest you go at about 1.21 for sequential use. BTW do not DIY. Bring it to a machine shop-if you mess it up a little, there goes your housing! If you do it too much it will then leak and you won't be able to raise boost even to stock working pressures.

To take off the turbos:get under car, take off downpipe, disconnect oil lines(x2). From top side: remove air intakes, remove airpump, remove Y-pipe, disconnect water+oil lines, disconnect any vacuum hoses. Get under car again:remove aluminium air intake, remove studs or bolts which actually connect turbo to the exhaust manifold. Done. Ok?

1.21 that is about 30.7mm right? How big is it STD?

I was thinking to do it with my grinder but you think its better leaving it to a cnc machine? I have a friend who works with such a things.

Nice to hear I dont have to remove my engine to get the turbos off. cause thats what I have heard.

I got my Pettit ECU today so maybe I will torn my engine compartment apart next weekend to do the job.

I would have sold you mine for 250euros, it's really not that hard if you have something to raise your car onto. I have posted it somewhere else today what to take off and which order. I'd say do it to 31mm and definetely don't do it by yourself. If you look on the european forum I have some things for sale.

Ok. I paid 370 US $ for the pettit and he got my old one, I also got the unlimited chips. (half price) I got it delivered to my door by the guy and tested an my car and everything so I am satisfied.

I think my friend will port it for me with the CNC machine, those computer controlled things will do it.

European forum..WTF you have a seporate forum too.
man.... and you sell stuff. what's teh euro-dollar conversion right now?
what's the web address for that forum?

I ported mine with a dremmel and a metal cutting bit, alternating with a 1" grinding stone on my die grinder. I marked a line around the edge of the "flapper" and ground away about 1/2 way to the line.. I think I went about 10% larger. I have no problem with boost.. I have the normal 12-8-10-9 boost patter (see my dyno plots).. I am concerned that I did not go far enough, but time (and the powerFC) will tell, I am in the process of upgrading my intake now.

I have pictures if anyone is interested. I also have 2 extra exhaust housings (one is brand new stock Mazda). The one on my car is ceramic coated (another DIY) (Had to use the oven when my wife was out shopping though =)

Dan

FYI.. If you have never removed your down-pipe / precat, be careful, use lots of heat when taking the nuts off, the stock Mazda nuts are distorted to help “lock” them on. If you snap one of these, it will probably be ok, as you are taking out the turbo anyways. You can even get away with snapping one in the exhaust manifold, but sooner or later, if you are breaking / stripping studs, your going to have to pull the more to helicoil you rotor housing.

I used stock Mazda studs, and nuts with lock washers from my local ACE hardware, they have saved me tons of frustration in taking on and off the turbos and down pipe.

yes I would like to se some pictures, you can send them to gzon@home.se

I have already removed the Downpipe and made a new one so thats no problem. I removed intake, cast intake, Y-pipe, intercooler and pipings then so it wont take much time to do it again.

all this talk of Sequential turbo's...I CAN'T WAIT to go single.....

Here are some post porting pics, I probably opened it up about 1/2 the way from stock to the edge. I have the housings ceramic coated (grey), and used a blue sharpie to mark the outline of the door...

one

And Another

What a PITA! DAMN!@#$