ej20 turbo

[twilightprotege]

well it appears i will be getting an ej20 in the very near future and i'm trying to work out what turbo is best for my car. naturally i dont want earth shattering power, just as much low down and mid range power as possible. since the engine i'm looking at will be either twin turbo or have no turbos at all, i will be doing a single turbo ej20.

having a quick look through the info i can find, it appears the vf35 is the best turbo, although not the easiest to find, for low-mid range power. namely this is because of the smallest exhaust housing, but still a decent size compressor.

any thoughts/suggestions/experiences etc???

[phillatdarwin]

what about a vf28

[twilightprotege]

according to what i've read (even on here) it has the largest exhaust housing (P20) - would certainly take longer to spool and make lots of top end power - opposite to what i want

no other comments???

[phillatdarwin]

from what i have read a vf28 will make boost down low at about 1100rpm and max boost is made at about 3600rpm .But will only make about 17psi boost
have you read this
showthread.php?t=3394
and i have this info as will
http://www.ausubaru.com/wiki/index.php?title=TURBO
have a read of this .good info

[discopotato03]

I think a good budget turbo is to get the std TD04L-13T/6 rebuilt with the TD04HL turbine and maybe the 15T compressor wheel .
It makes a great in between size as in between the Std TD04 and the a bit too big TD05 .

The original TD04HL-15T turbo was I believe only available on some JDM Rex wagons and almost impossible to get .
The turbines and compressor wheels are available and you can have your original 6cm turbine housing profile machined to suit .

If you want a new BB turbo better off with a Garrett core/cartridge because they use more modern wheels IMO than IHI does . GCG sell turbine housings to suit the EJ up/down pipes and a compressor housing shouldn't be too hard to organise .

How much do you want to spend ?

A .

[Outback bloke]

since the engine i'm looking at will be either twin turbo or have no turbos at all, i will be doing a single turbo ej20.

If I have read this the way you mean it I think you need to be advised to not go this way. Seems you are wanting to get a twin or none and convert it to single. An expensive way to go converting the twin and a difficult/expensive way to go converting a non-turbo.

Just buy a single turbo motor to start with then worry about what turbo you want later. Try and buy an under manifold intake motor. This will make it a lot simpler to swap turbos later.

If you are wanting the engine for offroad use then I suggest the VF28 or a TD035 (Forester) Both are very fast spooling. The Forester turbo is no doubt the cheapest option.

the std TD04L-13T/6 rebuilt with the TD04HL turbine and maybe

There is absolutely no need to stuff with any turbo by changing or modifying things. There is two very good options listed for you here and they are readily available if you happen to have one fail. Simply pull it off, throw it away, bolt on the new one and you are done. Buying and then building a turbo will cost as much, if not more, as the motor you are going to be buying.

How soon do you want one? I have a friend that owns a major importers and he has asked me if I have a shopping list for him. I could get him to get you a Forester turbo engine or front cut.

[twilightprotege]

outback - sorry, will definately buy a turbo engine, it'll just either have no turbos on it, or the original twins - i'd definatley get a single turbo over a twin if the price was right, but i havent found any good ones that arent old (really only want an engine thats no more than 10 years old). if you can get me a price on a newer engine or front cut (engine only preferred as i dont want all the extra rubbish, however if the bits can be sold off to make the engine cheaper....i'm all ears) that'll be great and i'll definately be interested - just pm me. and what do you mean by under manifold intake motor? i assume you mean the air intake to the turbo goes under the intake manifold rather than somewhere else?

phil - yeah i did read that page - it's everywhere over the internet, which is why reading through it i thought the vf35 is the best option

disco - basically looking to spend as little as possible! lol i'd prefer to get a new garrett turbo, but they are twice the price of a very good 2nd hand ihi unfortunately

[phillatdarwin]

i do not know if u have read this as the info on this is good to read .
No responsibility is accepted for incorrect data

IHI turbo specifications and comparison sheet


Comp
Inlet
dia
Turbi
ne
casti
ng
ID &
batch
VF22 suwe037e Roller 48.5 A 9.4 94001 0.71 5 11 C395 H
brg PZ20-H H4
15w
VF23 suwe037b Roller
brg
46.7 B 9.4
PZ20-H
94001 0.71 6 11 C395
8psi
TBA
VF24 suwe037d Roller 46.7 B 9.4PZ1894001
0.63 6 11 C418 H
brg H 8psi S4
66
Vf25 Tba TBA 38.2 D 6.2PZ12 62004 0.36 TBA TBA TBA TBA
VF26 suwe037g TBA 38.2 D 6.2B14 62004 0.48 TBA TBA TBA TBA
Vf27 Tba TBA 38.2 D 6.2pZ18 62004 0.63 TBA TBA TBA TBA
VF28 tba Roller
brg
46.7 B 9.4PZ18H
94001 0.63 6 11 C395
8psi
TBA
VF29 SUWE037k Roller
Brg
46.7 B 9.4PZ18H
94001 0.63 6 11 TBA TBA
VF30 suwe037h Bronze
Brg 47.9 C 9.4PZ18H
94001 0.63 6 11 C484 H
S4
IC
F55
Garret
450500
suwe038a Ball
Brg
53 --Outlet
dia 46.9
-7 10 14psi
Garret
400
suwe038b Ball
Brg
53 --Outlet
dia 51.5
-7 9 11psi

Page 1/5

NOTES


Typical applications

The “VF” series of turbo’s all have straight inlet paths, so when fitting to early Legacy/Liberty and
WRX’s they need major changes to the compressor housing to take the elbow inlet. OR a modified
inlet manifold is required.
All VF series turbo’s are manufactured by IHI, Japan
Typically all Sti models come with a IHI turbo, and All WRX’s come with a Mitsubishi turbo.
WRX’s Ver 1,2,3 all came with TD05 turbo’s with a 90 degree elbow inlet, whilst the later Ver 4
and 5 came with a TD04 that had a straight inlet path and was slightly smaller for better bottom end
performance and less lag.
All VF turbo’s and older units have built in waste gates.

Exhaust fitting and design

All VF series turbo’s feature the same bolt pattern and exhaust joints, so swapping them is
relatively easy.
The critical part is the design of the splitter for the exhaust collector. As the VF turbo’s have a
different depth to them when compared to the factory TD04 and TD0505. Meaning if you swap
turbo’s you should adjust the length of the splitter. A Splitter made for a VF turbo will be too long
for a TD04/05 (the exhaust simply wont bolt up) and a splitter made for a TD04/5 will be too short
for a VF and hence allow gasses to mix too early causing an increase in lag and less power. (for
more data on this exhaust feature refer MRT Performance)

If you require a turbo larger than a VF22 MRT recommend a Garret 400 – 450 roller bearing unit, if
you are building a serious drag car then a larger turbo with remote waste gate will be required

General

All of these above turbo’s have a 60mm Outside Diameter inlet to suit the OE inlet pipe.
Size of Turbo should be also considered for gas flow. With high output engines and or large
capacities, the physical size of the waste gate (hole) will be a restriction when added to the turbine
(hole) This is like fitting a big engine with a small restrictive exhaust

Hence the need (in some cases) for remote waste gates.
A remote waste gate will flow more, because it is larger, and effectively give better boost control.
The downside is they are awkward to fit and difficult to tune with the OE ECU.

Page 2/5

VF22


WRX Japanese domestic market
Best turbo for high output engine. Highest capacity of all IHI “STi” turbo’s. OK for high boost or
stroker engines. Best fitted with cars that at least have a front mount intercooler. Not recommended
for really big boost stroker engines or cars that run over 25 psi boost.
Same Turbine housing and wheel as a VF23 (20) with larger Compressor housing.
Only fit this turbo if you have at least an exhaust, front mount intercooler and air inlet mods. Its
good also if you plan internal engine mods.
This turbo has the most lag of all the VF series.


VF23


Sti Ver 3 June 1996
Good all round turbo with straight inlet path
Same compressor housing and wheel as a VF24 with larger Turbine housing (20)
Great turbo for mildly modified cars and those who are unsure of their plans for the future

VF24


STi ver 4, June 1997
Common for Group N rally cars and has good bottom end. Not recommended for stroker engines or
engines with high boost as turbo is small and can over speed.
Same compressor housing and wheel as a VF23 with smaller Turbine housing (18)
Best turbo for Auto’s and cars that want the best bottom end and least lag.


VF28


STi Ver 5, June 1998.
Basically the same as VF24

VF29


WRX Japanese domestic market
Basically the same as VF24 except has a different location for the pressure hose on the waste gate
actuator
Compressor wheel is slightly different.

Page 3/5

VF30


STi ver 7Oct 2000
A totally new design and shape “VF” series turbo
Common on Group A rally cars where more capacity is required than is possible with the VF24.
Good turbo as compromise between the VF23 and VF22, as it has the same size turbine housing as
a VF24 and a compressor housing similar to a VF 22
A relatively new turbo to the market and still being “tried and tested” early indications are it will
replace the VF 23, with slightly more capacity.

Garret 400 HP

Bolts to manifold ok, but requires some modifications to fit due to size of compressor housing.
Also requires minor mods to oil drains and supply lines.
Should only be fitted with at least a Electronic Boost controller and works best with a whole new
ECU
Designed for cars that are going to run over 20 psi and produce over 200Kw at the wheels (4WD 4th
gear)


Garret 450 – 500HP

Similar spec to 400 hp just bigger!
Bolts to manifold ok, but requires some modifications to fit due to size of compressor housing.
Also requires minor mods to oil drains and supply lines.
Should only be fitted with at least a Electronic Boost controller and best with a whole new ECU
For cars that are going to run in excess of 20 psi and over 200Kw at the wheels (4WD 4th gear), IE
Stroker’s, big head work and CAMs.


Page 4/5

VF23 TD05 (left) and VF 23 (right) VF23 TD05 (left) and VF 23 (right)
TD05 (left) and VF 23 (right)
VF24 inlet, 6 blades
VF30 turbo
TD05 (left) and VF 23 (right)
VF22 inlet 5 blades
VF30 inlet 6 blades
MoTeC / Haltech / Link and factory EFI Specialists

NOTE

Refer depth of
castings at
outlet.
VF turbo has
much less cast
steel at outlet of
turbine blade.
A critical
dimension for
exhaust outlet
splitter designs

NOTE

Refer blade
number and
shape

NOTE

Different water
supply pipe to
turbo bearing
assy.


if u want i can email u it in pdf

[discopotato03]

Yep no worries we all have to eat .

I take that much copied list with a large grain of salt because I think it was generated by someone/s that can't see beyond OEM and WRX's .

The manufacturers have all kinds of reasons for making alterations to turbocharger specs and most often it has to do with differing states of tune with their engines and how they went about it . This is why you cant expect to take one test mule engine and run that whole list of dryers and mimic those impressions - the engines themselves can have very different characteristics so its more than just the turbocharger .

For cheap and cheerful I'd stay with the basic TD04L because they are plentiful (read cheap second hand) and boost from relatively low revs which makes them a good general purpose unit on an all round EJ20 turbo engine .

Personally I don't like the TF035 Forrester GT turbo because its basically very small with a large waste gate flap valve so the things boost quickly and run out of puff equally quickly . This is fine on a very low CR engine that needs torque at nothing revs - EJ20 pulling round a reasonably heavy Forrester .
In a car that was a bit lighter and an engine with a better slightly higher CR the TD04 is a better all rounder IMO .

With pricing , I hunted around a found a TD04L with flanges gaskets water plumbing etc for $250 which is real good buying . The cap on backwards REX pilots can't get then off quick enough so easy to buy cheap .
The ball bearing , hate morons quoting roller bearings because NO turbo uses roller bearings , IHI's are dearer second hand and supposedly a good price is $600 plus . IMO the smaller ones don't have a particularly good match of compressor and turbine - or turbine housing size for that matter either .
I'm not sure that you can buy new cartridges for the if you lunch one or if parts exist to rebuild them .

Lastly that insight into the larger TD04HL was aimed at people who want a bolt on turbo that goes better than the std TD04L but looks and fits exactly the same as std - because its only internally different . The compressor and turbine used ARE available std in Mitsubishi OEM turbos for European cars like Volvos and Saabs but the water in/out is slightly different with a factory TD04HL cartridge . I did mention Subaru using it themselves but hard to find an original one with water fittings to suit an EJ engine .

Others won't agree but the twin turbo engines are a lot more complex than they needed to be and were a result of Subaru refusing initially to go town the single twin scroll turbo route like Mitsubishi etc .
It you can find an original twin scroll turbo engine that would be the cats whiskers because most of the goodies are factory fitted , some later Legacy GT engines are twin scroll turbo type and they make real good torque at low revs and still spin freely enough to have a great power range .
It what brings an EJ turbo engine on par power/emissions/consumption wise with a good twin scroll inline 4 engine .

I still have that TD04L here which I don't have a use for and owes me $250 .

Your call , cheers A .

[twilightprotege]

yeah a twin scroll would be a good option - afterall that's what they are designed for, however exhaust work for them is more expensive

and yeah, definately dont want a TT - way too complicated for what it's worth. twice the parts, twice the price (of repair), twice the amount of things that can go wrong (well almost)

but i just have to wait and see what engine i end up with, then decide on which avenue to go down