I have a uk 2 litre with the following mods:

440cc injectors
Sard fpr
Manifold and uppipe
Down pipe
Hks induction kit
Silicone turbo intake
forged pistons
genome exhaust


What sort of performance would i get out of the 20g?

Is it too big for my engine or will it work perfectly?

I have a vf22 that has gone pop so need to change to something similar or slightly better. Not looking for huge power but 360 would be nice

what you all think? is this one of the better options out there for me?

 

bigger injectors and aftermarket ecu will be needed
but the 20g will flow upto and around 390 bhp on V-power

not sure your gearbox would cope though

 

....for around 360bhp, I think you'd be better with an 18g as I'm sure they have a better spool time than the 20g, especially on a 2.0 rather than the 2.5 engines.


Cheers,
Grant

 

As RS.

 

well the 20 gives me more for the future

is there anything different when fitting it like oil lines etc or are all the bolt on turbos the same, just remove one then bolt another on

 

The oil banjo bolt is different on the VF and TD series turbos.

I believe the TD has a larger diameter restrictor in them allowing more oil into the turbo. If you use the VF one it will starve the turbo of oil IIRC.
Mike

 

where would i get the banjo bolt then?

 

I spoke to my AndyF about this and the VF banjo is fine to retain so I have.

Thinking about it afterwards, I'm guessing the newage STi has a small diameter hole in the banjo, could be to keep oil pressure to the AVCS, no 100% though.

What year UK turbo do you have?

For 360hp, an 18G would be better, with mine, I'm getting 1bar at 2800rpm,

Heres an over lay of my previous VF35 and my current AFP5/6 20G both mapped by Andy Forrest.



As you can see, there not a lot of difference in power or torque apart from the 20g just keeps on going.

The car is an STi 7 Type UK.

 

Oh, in answer to your question, what kinda power would you get from a 20G, I'd have a guess at about 350-360hp.

 

423 bhp on a 20g - Nice !!

 

Thanks

 

I had a 20g on mine and hated it. Lag was daft which made the car pretty rubbish around town.

Swapped for the 18G which suits me down to the ground. May have lost some top end grunt but this is more than made up for in the mid range which is quite frantic.

Was an expensive lesson for me but one I'm glad I tried.

 

cant fault the 20g on mine. 362 bhp at 1.55 bar at the mo

 

but surly the lag is not just solely down to the turbo ...mapping is the key to eary spool up is it not also?

 

That is correct

Along with a number of other things

 

mine is a 1997 uk turbo.

with the vf22 i got 340bhp so hopefully will be able to get a bit more out of the tdo5

does it just have a standard size intake or are there any mods reauired to fit the turbo?

 

Agree. Nothing wrong with the map and was done twice but two very respected mappers. There's just a road that I need to drive on every day with a sharp left up hill junction. In the Mrs' 306 HDi second aint a problem. Used to have no issues with the VF35 but with the 20G had to change in to 1st every time otherwise it would stall.

The 18G suits my driving style. Spool is very similar to the oem VF35 with supporting mods (ported headers etc) but noticeable difference was in the mid range. It really does put the power down well. I'm pleased I made the change.

 

Yeah right

 

there was a comparison graph of the 18g and 20g and tbh the midrange wasnt that different.

dont know where the graph is now but its on here somewhere

 

Just to clarify - Nick is running full decat, 10% methanol in V-Power and a liberal splash of NF

 

Mine is a Forrest 20g & map with Apexi/550 injectors/ Vmax+NF/headers/FMIC etc etc and it musters about 370 bhp, maybe 380 on a cold crisp morning...

Spool deep down can be lathargic, but keep it above 3500 and the car is a flyer.
This is all on a stock Sti V3 long engine.

 

what aboit fitment.
is it just a bolt on replacement no intake mods?

 

I have a 20g in a 1999 sti don't find it much of a problem 380bhp 1.7 bar. we also have all the internals to take the car further if we want to.

 

Yes, it is a straight fit, with the original inlet pipe.

Andy

 

what internals r u running?

 

Very True

 

Running:

Lateral 800cc matched injectors
Aps circ/re-circ dump valve
Apexi power fc ecu
Apexi avc-r boost controller
fmic
3.5 full decat system ( very loud )
uprated oil pump
lightend fly wheel
Racing clutch
Gruppes unequal lenth stainless headers
k & n induction kit
TDO5/O6 20g
Knocklink
Lambdalink

i think that's there maybe more hope this helps not cheap thou

 

u any forged internals?
pretty similar set up though i dont have the clutch or flywheel and I do have forged pistons

 

no forged internals but at some point may take it up to 450-500bhp change bottom end and put in a 6 speed gear box to take the extra power but i want it to be reliable as it's used every day for the school run.

 

380 bhp would be awesome in a classic, i thought 340 was sharp enough lol.

i would love mine to be able to push that sort of power.


What sort of boost are these turbo's capable of then? or is 1.7 bar pretty much it without pushing it to destruction?