masterx81

iTrader: (4)

Hi!
I'm trying to figure out what turbo are avaiable on stock position with ball bearings for made 500bhp on a 'wiseco' stroker 2.123 engine...
I've found the ATP gt3076r, but maybe it's a too bit small for that power.
What are the other competitors?
Thanks!

banny sti

iTrader: (68)

MD321V

Banny

masterx81

iTrader: (4)

With what core is made the MD321V?
The ATP has also a nice version with integrated EWG (that maybe can help discharging the exhaust gas with the 'small' .72 housing...)

Other alternatives?

Thanks mate!

banny sti

iTrader: (68)

It is garret core afaik but best to double check with Mark @ Lateral performance. You could also speak to engine tuner regardinf their S206 turbo.

Banny

masterx81

iTrader: (4)

Uhm, i'd suppose that all this turbos are built with the gt30 core.... All ball bearings, all similar power ranges... So i'd suppose that also spool time are quite similar...
I've checked the s206, it need a custom downpipe

Ian

iTrader: (10)

the s206 down pipe is around £225 deliverd, and the cost of the turbo is cheaper than the v

joz8968

iTrader: (13)

Also, there're these...

SC50 billet ................£1350.00..(roller bearing)
SC54 billet.................£1425.00..(roller bearing)

Plus VAT.


See here:-

https://www.scoobynet.com/799025-sco...better-18.html

Shaun

masterx81,
Not ALL of these turbo's have a GT30 core.

You could also look at the AET unit that uses a 3076 core and is what I use (standard position and fitment). The power figures in my sig relate to what is possible with this turbo, that I have achieved.

masterx81

iTrader: (4)

Looks nice, on the site the say that are based on the gt30 core (that it's bb), but say also that are roller bearings.... Custom core?
The possible candidates are growing so much!

I think most of them.. It's easyier to use stock core and put custom covers that develop a custom chra
The AET unit looks so good... I'll go to see on their website...
Would be nice to know of every unit the trim of the wheel, diamaters, ar of the covers and so on, but only few publish this data

masterx81

iTrader: (4)

The AET unit looks so good... I'll go to see on their website...
Would be nice to know of every unit the trim of the wheel, diamaters, ar of the covers and so on, but only few publish this data

Maybe i've also forgot to say that the engine will be full built, with ported heads/kent sub03 cams, and every sort of mod that it's possible

Shaun

You should take into account the complete build though. I would not try to make out that the kind of power I have achieved is the norm on all engines specs.

masterx81

iTrader: (4)

And that's is why i'm searching also full specs of the turbos (like wheel diameter, trim, a/r, etc), or at least know what's the core that is used
A complete compressor map would be better, but for an hybrid unit, maybe it's too much, most of the people put what seem better...
And this is why i've opened the thread

masterx81

iTrader: (4)

Someone have some info's on the AET biggest unit or know where i can find them?
Thanks!

Lateral Performance

iTrader: (20)

I would recommend that anyone considering buying ANY turbo, base their decision on a turbo that has been proven to produce consistent results, across numerous engine builds, and different mappers.

If you buy anything based on a "one off" result, that no one else has achieved, you may well end up being very disappointed !

Whilst the GT3076/ GT30R works really well in it's original Garrett housings, it's consistently AVERAGE when converted to a "bolt on", and this applies to EVERY version I have come across, including the numerous versions of it we have tried.

Shaun has had the only good result I've seen on this turbo, but he's also using £3500.00 of Cosworth up rated heads/cams, and this should be absolutely taken into account when being considered.


Mark.

Shaun

If you want details on the that turbo call AET Turbos and ask for Andy Taylor (MD) on 01924 228042. I believe AET are working on updating their website with the various turbos available for the Subaru. Just tell him you have been speaking to "Shaun from ScoobyNet" and he will know what turbo you are referring to.

masterx81

iTrader: (4)

I'd totally agree... Changing only a cover of the turbo for sure modify the way that garret has engineered it... Hybrids are always a compromise...
I've not intention to use that expensive heads, but i've done a bit of work on mine, using as base the v3/v4 heads, that from what i've read over the net, as original are already quite good. I've a set of supertech valves waiting, bronze guides, seat work, kent sub03 cams, etc...
I'm only triyng to figure out what it's considred the best bet to try... I'm restricted to use oem location as here in italy it's illegal made any mod on the car, and i'm trying to get the best in the most invisible way that i can, else a rotated setup gt3076r was my first choose (due to some calculation and from experiences that i've read over the net...)

Uhm, i've forgot to compile the profile, but i'm italian, and i'm quite bad speaking english (as maybe you have seen, i'm not that good also writing ).
I'll hope that they update theyr website soon

joz8968

iTrader: (13)

On the contrary, I was actually thinking your English, what it with being your 2nd language, is very good. (I hope that doesn't come across as condescending BTW - not meant to ).

In any case, don't apologise to us British, as we're lazy buggers who baulk/are generally crap at learning other languages.

MartynJ

Couldn't agree more Mark

masterx81

iTrader: (4)

[OT MODE ON]
Thanks mate
I don't think the british people are lazy, simply the english language can be used to comunicate all over the world, so there isn't a real need to learn other languages... If an italian want to speak with other people, MUST learn something else
I'd like too much to exchange my ideas with other people, and using internet it's a really good way, but i'm only 'good' to write, as i've never the occasion to speak with someone with this language... Maybe sometimes i try to listen some tv shows in the original untranslated language, but something is always missing
[OT MODE OFF]

Shaun

OK.... with me being a total engineering numptie how can heads with bigger ports and valves provide me with an advantage powerwise, when it has already been proved that the standard STi heads are capable of flowing more than enough air for this type of power. Cams I accept can move the band around.

I would appreciate fact not theories.

This is not a dig but a genuine question as the "but your using £3500 of Cosworth Heads / Valvetrain" keeps popping up.

masterx81

iTrader: (4)

Also if the heads aren't the 'choke' point, working on them (increasing the valves, porting, etc) has a SIMILAR effect as use cams with more aggressive timings.
See the power that an head can flow as a 'time-area' relation. Time that the cams mantain open the valves, plus the area that the opened valve allow. As using aggressive cams shift up the powerband, working on the heads have a similar result.
More you are near at the 'choke point', and more are the restriction that air encounter entering in the cylinders.
For sure you can't get power all over the rev range. If you tune the heads for have good velocity at high rpm, you have less turbolent (and also less homogeneous charge) air at lower revs, while using small ports, you are having a choke (or at least, nearest at the choke point), but at lower revs you are getting more power due to the more turbolent airflow.
The same high flowing heads will have more power on EVERY turbo that you bolt on. But if you go too 'large' for the power that you want to made, you have move too far the rev range, losing power where you need.
This is theory, but it's also 'pratical'. If you work your heads, you WILL gain top end power (up to a limit)
All depends on the velocity and turbolence of the air/fuel mixture.
Plus, there are other factors that the ducts in the heads are tuned for, like swirl and tumble effects, and changing them can change drastically how the heads can perform.
See it as more you are far away from the chock point, more you are gaining power (maybe loosing it in other rev range). Move too far, and at the same rev range you are gettin less power (but maybe more power upper on the rev range).
The best thing that a tuner can do on the heads is gain flow, but maintaining a good turbolence. Actually, it's quite difficult. Speaking about heads, flow isn't the only thing that made power....
EDIT
Just for curiosity: Some time ago i've done some calculations on the mach indexes of the subaru ej20 valves (not the simple calculation that can be found on the net, calc found on an egineering book), and in the worst condition they was able to cope also a 2.2 displacement engine at 8000+rpm... So the valves are the last thing that you want to enlarge (if you remain in that rev range with that displacement). Note, this are only valve calculations, porting the ducts still can made better usage of that massive valves...

Uhm, the MD321T+ isn't rated for 500bhp, but a bit under. Reading over here seem a quite good turbo (and well proven), how can be compared the spool times with the other 500bhp turbo's ? 500 will be my mark, but if i made 480bhp with the turbo playing hard 1000rpm sooner, i'm also quite satisfied

joz8968

iTrader: (13)

Indeed.

That's why we're "complacent" (lazy?) when it come to learning languages - as we don't really have any need to.

I best embark on my Chinese Mandarin course..... lol

Shaun

I understand all of that, to a degree.

It's interesting that even though my heads have been opened up and valves are bigger, I do not appear to have experienced any issues with any decrease in power / torque lowdown, when comparing against others who have the OE STi heads as a benchmark. This was even apparant before I moved to higher compression.

I still don't understand how the statement of "you have Cossie heads/cams so no wonder you have more power" is the ONLY reason why I have achieved the levels I have, on the turbo I use.

Unless you literally took my engine and replaced the heads with OE STi heads, could you ever substantiate the previous remark. Let's be honest that is never going to happen on my engine.

The only other option would be to try another turbo by another supplier..... if the logic is sound then surely whatever previous results that "other" turbo has achieved on other builds, will be increased on my engine!

So a turbo with a GT32 billet turbine should make a shedload more power on my engine... right?!

masterx81

iTrader: (4)

Don't worry, i do know only italian and english Maybe a bit of french, because my local dialect (piedmontese) have some common things with french

Maybe when you have put on the heads you have made some other things than can have increased the low end torque, only a bigger turbine can contribute increasing VE in the low revs, due to less restriction on the exhaust and less backpressure. Or also better intake...
It's quite difficult to compare 2 engines, too many variables to take in account
The only way to valuate the benefits of a mod it's to change only one variable at time, but also in this way isn't accurate... For example, in you open up a lot your heads, but for take advantage of them you need a bigger intake headers, using this heads with a smaller headers made the mod quite useless (and maybe can have also negative effects)

Shaun

Nothing different to the heads other than what I have stated. Intake has been "cleaned up" as regards to filter type and location, as the original inner wing filter was causing a restriction. I am also still using the original JDM twin scroll (untouched and standard) tubular headers, which seem to be very good and certainly reliable (they have done over 40k miles so far). The up-pipe is custom to go from twin to single scroll for the current turbo.

As you say, it is hard to pin point exactly any single item that "makes the difference".... but as a complete package it certainly works.

MartynJ

This is a graph from a recent S206 install. As usual, DON'T try and interpret spool from it, as you can't from a dyno test. The power output speaks for itself!
This is from a 2.1 stroker, based on an open deck block!
He's tracked it, dragged it and flung it all over Cornish roads, so I think we can safely say that our view on these blocks is justified.

masterx81

iTrader: (4)

Maybe they was able to increase the flow while maintaining a good mixture of charge, with a good combination of cams and port shape/seat diameters. I don't know. Maybe a rubber mold of the ports can explain how they have worked...

masterx81

iTrader: (4)

The open deck block has survived on that power levels? Quite strange, i've seen some 400bhp engines with cracked cylinder walls .
For strightenin my block, i'm doing a closed deck 'coversion' using some custom milled 15mm block guard (milling also the blocks for have a good 0 interference fit).

I'm a lot interested on the spooling characteristics of this turbos.
Actually i don't think that a 500bhp engine will beat a 470 bhp engine that spool (and so have torqe sooner) for example 1000 rpm sooner...
I'm trying to get the best match for that power levels...
Actually, i'll do know that spool time can change A LOT based on the type of mods that there is on the engine (portings, heads, etc).
But i'm trying to figure out an 'Average' result...

Shaun

Welcome to the world of the UK tuning scene. I also do not use a CDB, oe 2.5 standard linered block case.

masterx81

iTrader: (4)

It was an uk tuner that has advised me first to not try to go over 400bhp on an open deck block... Doh!
After that i've seen some bad shots of broken cylinder walls, and before destroy the engine, i've converted it in 'closed deck'....
Here in italy the 2.5 engine has quite a bad reputation... Some people have reported that also as stock the cylinder walls have cracked, and with power increases are a really weak point...