ClassicWR1

iTrader: (3)

hi everyone...

Ive been told the next thing i need for more power from my STI is bigger injectors, so my question being -

do i just put on some 440s(that seem to be quite cheap atm) or am i best waiting and getting the 550s???
Is there really that much difference in regards to the power difference they would make??(obviuosly a re-map would be needed to....)

Also, when would someone need to install a fuel regulator???


All opinions and knowledge very welcome.....

bighead

iTrader: (1)

if yr going high power 320bhp+ then you should fit a fuel regulator and also an uprated fuel pump, and I personally would fit bigger injectors than 550s , so if you decided to go higher up the power ladder , you will not need to change the injectors again ( same applies to the turbo as well )

bighead

iTrader: (1)

just to add injectors don't make power ....the bigger you go the more fuel they are provide the engine ...a must if you are going high power

Marx Mcrae

iTrader: (4)

What year STi do you have? If its a 97 onwards then it already has 440's.
If you add a fuel pressure regulator then the 440's will just about cope with 350bhp (with supporting mods) After that your gonna need some 550's.

It just depends on what power you are aiming to achieve

ClassicWR1

iTrader: (3)

Hi everyone...
my engine was built by BGV Engineering to spec as follows;

FULLY REBUILT FORGED STI ENGINE,
OMEGA FORGED PISTONS,
MANLEY H BEAM FORGED CONRODS,
V9 STI NITRIDED CRANK,
ACL MAINS AND BIG ENDS,
V3 STI PORTED AND POLISHED CYLINDER HEADS,
PIPER CAMS,
NIMONIC EXHAUST VALVES,
NEW TIMING BELT AND TENSIONERS.

new tdo5 turbo and other supporting mods like fmic, fuel pump, uprated clutch, gearbox and centre diff, lightweight pulleys etc etc....

the 2 maps that have been done most recently were just over 300bhp and 320bp.

So what you are saying is i certainly need to be fitting a fuel regulator and if i ever want to go past 350bhp its the 550s yes????
Just out of curiosity people - 350bhp+ would require what else alongside all this....


thank you to everyone for your help!

Andy

bighead

iTrader: (1)

yes uprated fuel pump and regulator

a stronger gearbox, bigger turbo, 550s or 650s even better, aftermarket ecu , free flowing exhaust and a good mapper

Marx Mcrae

iTrader: (4)

Bigger turbo for a start depending on what TD05 you have. 16g 340-350bhp, 18g 360-370, 20g 380-390bhp.
550 injectors.

Please tell me you kept the V3 cams????

Marx Mcrae

iTrader: (4)

Bigger turbo for a start depending on what TD05 you have. 16g 340-350bhp, 18g 360-370, 20g 380-390bhp.
550 injectors.

Please tell me you kept the V3 cams????

ClassicWR1

iTrader: (3)

Unfortuantly i didnt get the engine done mtself, so the turbo i am unsure of??? likewise with the v3 cams too actually... sumfn of which i will have to explore and find out yes???

bigger turbo though, as in???....

stronger gearbox was fitted at roughly same time too accordint to receipts (unless your talking 6speed???), likewise exhaust and also apexi fc and avcr fitted and mapped by paul at zen.

so just to clarify... fuel regulator, 550s or 650s, bigger turbo and remapped!!!!
- HA HA, jeeez, i think i need a second job!!!!!

bighead

iTrader: (1)

if you going over 400 bhp you will need a third job

unless you have a uprated gearset fitted ...you will either need a 6speed box or a PPG kits for yr standard box .

turbo wise you could go MD 321 series...they are good for 400-500bhp or the garret Gt series for even more !!!

dabow

iTrader: (19)

for the spec you listed, id recheck whats fitted mate. the colour of the injector rips will help. also, the turbo

regards the box, upto 350ftlb your 5 speed will be put under alot of stress.
also, depends how far you want to go mate.
if like most, you want to stick with a good 330/340, 440cc injectors and a fpr will do you fine, as with a td05 16g

any thing more, look into boxes and a bigger turbo along with injectors ect

Marx Mcrae

iTrader: (4)

You need to set a target bhp figure, so you can get the parts you need.
what you dont want to do is get a turbo that is way too big for your needs.
What do the reciepts say for the gearbox. You need either a PPG gearbox or a 6 speed to kope with 400+bhp.

If your wanting between 350 and 370 bhp then the TD05 18g is a great turbo for the 2.0 litre. The 20g will produce more boost but os better suited to the 2.5's
if your wanting over 400bhp then you'll need an MD321 series turbo

Marx Mcrae

iTrader: (4)

You need to set a target bhp figure, so you can get the parts you need.
what you dont want to do is get a turbo that is way too big for your needs.
What do the reciepts say for the gearbox. You need either a PPG gearbox or a 6 speed to kope with 400+bhp.

If your wanting between 350 and 370 bhp then the TD05 18g is a great turbo for the 2.0 litre. The 20g will produce more boost but os better suited to the 2.5's
if your wanting over 400bhp then you'll need an MD321 series turbo

ClassicWR1

iTrader: (3)

Well i think thats me question answered thank you, there's Obviuosly alot of you out there that know your stuff thats for sure!

think judging by whats been said here i am probaly just gonna try to reach 350bhp...
anything more and the Mrs wont be going on holiday for a very long time by the sounds of it!LoL
So my shopping list is now as follows...

550 injectors
fuel regulator
and another mapping session!!

Thanks again to everyone who answered this thread, very very much appreciated!!

Andy

BRAVEHEART_STI

iTrader: (20)

550's are fine for that power leve;

ClassicWR1

iTrader: (3)

great news!!!

Will i need a remap if i install a fpr do you know??? or isit just best to wait till i get the injectors anyway???

bighead

iTrader: (1)

get all the mods that you are going to fit and then have the map the car ..otherwise you will be remapping everytime you have a new mods fitted and @£250-£300 a session , its not cheap !!

ClassicWR1

iTrader: (3)

yeah i understand that - commen sense really i know! Just wasnt sure if fitting a fpr would still require one is all???

thanks again everyone!!!!

Butty

iTrader: (2)

With that spec of engine build, I'm surprised higher flow injectors haven't also been added.
Can you see what colour the injector bodies are?

ZEN Performance

They are grey 380cc injectors, I mapped it a little while ago and it maxes them out at 0.95 bar to make around 300hp. The turbo is already a TD05.

ClassicWR1

iTrader: (3)

Thanks again paul!

harvey

iTrader: (48)

Grey 380cc Classic injectors max out with the OE FPR and a new Walbro GS341 255 lph fuel pump between 280 and 300 bhp.
Yellow 440s will run to around 325 bhp.
Side feed 550s which can be several colours including blue or dark red will run to just under 400 bhp on the OE FPR.
740cc injectors will take you well past 500 bhp.
You do not need an adjustable aftermarket FPR unless you wish to extend the range of your injectors. A 16% uplift in pressure will typically give 4% increase in power which means you can get yellow 440s to operate to around 340 odd bhp and sometimes a little bit more.
Fitting injectors on their own will not increase power and if you change injectors you need a remap just as you will have to adjust the fuel map if you change the FPR.
TD05 16G in good condition will max out somewhere around 340 bhp and as Max said an 18G is generrally around 360 bhp and a 20G somewhere past 380 bhp. Good ones occasionally make more than 400. The MD321H does a similar power and the MD321T will do around 450 bhp.
You don't say what model or year of car you have but regardless of what Classic model it is, you will benefit from a front mount intercooler at the 340-350 bhp bracket without any doubt. You should also consider what you are doing with your headers as improving these will make achieving your power target that much easier. Either ported OE headers and matched uppipe or tubular headers with special uppipe at much higher power levels.
Take stock of what you want to achieve and why and then carefully have a specification that will achieve that, cost it well and stick with the proposed spec or you will suffer serious project creep.

ClassicWR1

iTrader: (3)

thanks for all that harvey, that is exactly what i was looking for my friend - informative and to the point as to what certain mods will do for me!

i do already have a/m headers and up-pipe fitted, with a tubular manifold and also a FMIC.
In your opinion though mate....

would i be better going down the 440s and aftermarket FPR or 550s and oe fpr already fitted??? (obviously map is needed too)

340-350 is as far as i want to go, really dont want to get in the situation of things breaking or god forbid - my engine/ gearbox/ clutch going bang!!!ha

dabow

iTrader: (19)

just a quick one, i've seen many scoobs get in the 340bhp, with 440cc injectors
and closer to 350 with a fpr fitted.

or is this different with the injectors being phase 2

harvey

iTrader: (48)

With 440cc injectors, Ph 1 or 2 you will need an FPR and a good bump in pressure to get to 340-350 bhp. Some rolling roads read more than others of course.

ClassicWR1

iTrader: (3)

So in your opinion mate (as you seem to know what your talking about!!ha) - what is best for my car...

440s and aftermarket FPR... or... 550s and standard fpr already fitted??? Obviuosly map needs altering also.

many thanks

andy

harvey

iTrader: (48)

Without doubt, providng there are no issues with your existing FPR you are better with 550 injectors.