itschrisfoo

did you have any issues taking off the wheel on the rotor master turbo. doesnt want o pull off as easy as the stock s5 turbo. am i missin someting. i took off the housing but now cant get the wheel off

RotaryRocket88

iTrader: (7)

Progress has been slow with my build, but last weekend I took care of the machining work that had to be done. My dad and I bored out the compressor housing to accept a larger wheel (going from 54.1mm U-trim to 55.4mm V-trim). At first I thought a CNC setup would be needed to follow the curve inside the cover, but after some measurements it turned out that the larger T04b wheels are also shorter. So all that was needed was a straight cut down the middle, and it would blend into the curve without any extra work.

Here are some pictures of the compressor cover after boring out the center, and cleaning up all the rough parts of the casting to squeeze every last drop of efficiency out of the intake path. A mill with a boring bar was used for those interested.

198713bt

iTrader: (2)

Awesome thread! Over the last few weeks I have torn a spare turbo down, and I have been looking for a decent T04B candidate to use as a donor to build myself a hybrid. I have had no luck finding one for a decent price. Does anyone have a decent place to buy one for relatively cheap? I don't want to spend $400 on a turbo that I'm only going to use the cold side off of. If that is the case I'd be better off sending mine to BNR

AGreen

iTrader: (11)

Just be patient and keep searching Ebay. You'll come across one soon enough. Don't just limit yourself to searching for "TO4B", search for "used garrett", "used turbo", "T3/T4", etc.


I found a chinese T04B/T3 hybrid go for $50 shipped the other day. It was brand new, but someone bought it and returned it because it leaked oil. They don't rebuild them, so they just let it go at minimum. Now, don't let it scare you, you're only going to use the wheel, housing, and backplate. No seals or bearings from China can be trusted. Buy a good rebuild kit from GPopShop and get one of those fake china-chargers and call it a hybrid.

198713bt

iTrader: (2)

Thanks for the advice! I'm a little leery of buying a chinese knockoff even for the wheel. From the sounds of it you think the compressor wheel is safe to use out of one? If thats the case I'll broaden my search


Also, is it worth paying the extra $60 for a 360 thrust bearing instead of the 270 thrust bearing?

AGreen

iTrader: (11)

I think on the first page alot of guys were saying it's perfectly fine to use the compressor housing and wheel. Not like air's going to damage it

I found a big one. You'll experience some lag, but damn will it flow at the top end:

http://cgi.ebay.com/ebaymotors/Garre...item45fb5ca8ee


Here's a backplate:
http://cgi.ebay.com/ebaymotors/Garre...item1c12a31294

A v-trim wheel:
http://cgi.ebay.com/ebaymotors/Turbo...item415acab06c

And now to find a v-trim TO4B housing.....

198713bt

iTrader: (2)

I saw that 60-1 on there. It is pretty tempting lol. My car is still quite a ways from getting back on the road so I think I'll just keep my eye out. I would rather buy a used turbo to salvage all the parts off of instead of piecing parts together. Should hopefully be cheaper that way.

incubuseva

iTrader: (13)

I'm wondering how BNR modifies the 270 degree thrust washer for better oil flow. Any clue about this?

bumpstart

there is several holes for oil pickup in the 270 bearing ,, heavy duty examples have three holes ( so does stock mazda )
as a educated guess i would expect any mods here would be to oversize these holes with a carby jet drill bit
- not that i see any issues yet with the current oil supply,,esp at high rotary engine oil pressures
the big issue with the 270 bearing is fast wear on either side of it caused by the thrust collar
caused by axial movement of the shaft when you overspeed them,, or oversize the compressor comparatively to the rear ,, or have excessive backpressure ratio
one of the methods to combat this ( with a 270 bearing ) is to double up on the spider washers within the cover plate

the other is to make the 270 bearing from steel and not bronze

and the third is to modify the CHRA with carefull drill and tap and fit the 360 bearing and its 2 part thrust collar

gxl90rx7

iTrader: (1)

why does the 360 bearing need bolting down, can u just use the spider washer thing like stock?

RotaryRocket88

iTrader: (7)

Good question. I always thought the 360 thrust bearing needed grub screws added because they wouldn't line up with the existing locator pins, but they actually fit right onto the pins used by a 270 bearing. This builder makes it sound like they may even bolt down 270 bearings instead of using the thrust spring: http://www.tamparacing.com/forums/bo...-upgrades.html.

bumpstart

and here is one of those "oil mods" ,, the restrictor pill for oil supply to the 270 bearing is removed on this hitachi CHRA
( i expect it is there because rotary oil pressure is so high , to limit the flow on to the front seal )

younG_Gunner

iTrader: (2)

Apologies first and foremost for the noob questions about to commence.

I've only recently started reading into turbo and begining to understand the dynamics of them. I was just wondering how big a turbine compressor would fit in an S5 housing? I'm unclear as to the measuring of things. I read up on FC3Spro and read that the H-trim compressor wheel would be a decent upgrade for the power I'm looking for (3-350hp) however what size compressor housing would I need?

Again, I'm a noob with this talk.

bumpstart

the H is off memory about 58 mm in the minor inducer ,, and 71 mm at the major exducer
this is beyond the practical limits of the mazda front cover,, the inlet will be paper thin and unable to hold the clamp for the inlet pipe

V is usually the one that can be hifi ( mazda cover ) ,, or added with the correct 0.60 garret cover and backing plate

so for H,, find the correct to4B backing plate and compressor cover set,, dont bother making it fit into the mazda cover

your other options for that sort of power are the 60-1 wheel which can be had hifi ( into a 0.6 AR to4B cover ) or into a 0.70 to4E/S cover

younG_Gunner

iTrader: (2)

So a t04b h-trim compressor wheel with a t04b compressor housing & backing plate should be ok with the stock turbine compressor? I'm only looking to make moderate power and the t04e seems like a high boost application turbo. I've read that the t04b setups work generally well in low boost applications.

younG_Gunner

iTrader: (2)

Stock turbine wheel. I believe that's what its called.

bumpstart

yes,, though you will need to port the wastegate,, and make a large dump pipe as it will be prone to creep
i find V ( one smaller ) is the point where you can sit in either camp
,, and the H is really starting to push the limits of the stock rear and you must make all the other little tricks to limit the back-pressure ratio to prevent a very peaky boost curve

if you look at the professionally built turbos at BNR they also sort of hint the same in their stage options

younG_Gunner

iTrader: (2)

Disregard this post.

younG_Gunner

iTrader: (2)

http://www.atpturbo.com/mm5/merchant...egory_Code=GCH

Would this be the correct compressor housing for the v-trim? V-trim comp wheel is 55mm on the inducer and 70mm on the exducer. Again, just learning.

AGreen

iTrader: (11)

look.... a candidate!

http://cgi.ebay.com/ebaymotors/Used-...item3cb9c9a6ac

RotaryRocket88

iTrader: (7)

No, that's for a GT28 turbo. The inside of the housing must match your compressor exactly. It can't just be close. If you have a 5mm gap between the inducer and the housing, the turbo will be horribly inefficient. The tolerance will be less than 1mm.

This is a T04B v-trim housing: http://massivespeedsystem.com/turbon...3/i-77489.aspx.

You can see there are others for use with H-trim or 60-1 wheels too, but these are fairly pricey. I haven't been able to find new Garrett housings, or even any vendors that know how to find one. That's where finding an entire used turbo has its benefits. You can get all the parts you need for ~$100.

198713bt

iTrader: (2)

Time to beat a dead horse.... which (if any) of these would be best for a mild upgrade (all around power, good driveability)
http://cgi.ebay.com/ebaymotors/T3-T4...Q5fAccessories

http://cgi.ebay.com/ebaymotors/Turbo...Q5fAccessories

http://cgi.ebay.com/ebaymotors/GodSp...Q5fCarQ5fParts

http://cgi.ebay.com/ebaymotors/T3-T4...Q5fCarQ5fParts

http://cgi.ebay.com/ebaymotors/Garre...Q5fAccessories

thanks in advance

RotaryRocket88

iTrader: (7)

I wouldn't buy any of those. They're all listed as "T3/T4", which basically tells you nothing. Seaching "T04B", and look for ads with dimensions on the compressors.

jal301

iTrader: (4)

For future reference - and for those of us considering the same build...

There are aluminum cleaners specifically for bare aluminum (note that there are some for painted aluminum which would not be applicable). I had some given to me for the vert wheels but never used it because I didn't believe that the wheels were bare aluminum. Was told by the guy who gave it to me that it works extremely well for campers / trailer cleaning.

I'd suggest finding something designed for the application instead of risking the use of a cleaner that isn't guaranteed safe for aluminum.

younG_Gunner

iTrader: (2)

Anyone using an s5 turbo with a 60-1 compressor? What's your supporting mods?