Advantages Of Upgrading Injectors?

[ontheranch]

Hey guys,

What are the advantages of upgrading injectors and is it normally a big job?

Cheers!

Pen

[Damo_R34]

on a stock car? nil. only necessary when fuel to air ratio required exceeds 100% injector duty, so unless your gonna shove a whole lotta boost through it, i wouldnt bother.

[Weezy]

very random question? "i feel like upgrading injectors"

[Import S13]

yeah only do it if your running more power then your stock injectors can handle or you need to change your injectors cause theyre stuffed.

[heslo]

Keep in mind, you'll need a retune. They aren't a plug and play affair

[Dohmar]

an upgrade in cc never hurts if ur current ones are out of life

however, it will require a retune, as whenever you replace an AFM or injector CC it changes the K constant, which is the coefficient between the fuel pumped into the cylinder and the standard amount of air aspirated (these things are calculated off boost)

bigger injectors have no reliability improvements over brand new replacements of the same size

however you can run more boost with a bigger injector, and the duty cycle is reduced (which probably means something technical but i cant be stuffed looking it up).

if ur not modding the car tho, id say stay with std size, simply so u dont have to pay for a retune.

if ur gonna change stuff, get the big uns

-D

[jrm]

On a related note, I've seen my R34 hit 93% duty cycle on a cold night. Scary for what's essentially a stock car + exhaust :S

(I imagine a retune will get that down though, as R34's are known to massively overfuel as soon as the boost increases..)

[SLED]

Penny, if the existing ones aren't stuffed and not running anywhere near 100% duty cycle (which they won't be on a stocky) then the gain of bigger injectors is zero.

[ontheranch]

Thanks :-)

yeah random question, I like the education but also I have had a strange small hesitation when I go to take off fast, just before it hits boost and as soon as the turbo kicks in then it's all good. It doesn't do it all the time and it's minor but I heard it could be injectors. I may be imagining it but the last two days it seems to have stopped, but it feels I've lost some power....

[SLED]

going from NA to Turbo, you're probably experiencing what we get every day Penny......Turbo Lag.

Welcome to Forced Induction

[Dohmar]

going from NA to Turbo, you're probably experiencing what we get every day Penny......Turbo Lag.

Welcome to Forced Induction

this is true however the transition stage should not be providing a drop in power

it happens often, either because of too much fuel or not enough -it has to be precisely tuned to ur turbos

that said, if its already as tuned as u can go, camgears and possibly poncams will help mitigate that

;D

-D

[SLED]

poncams on a stocky will push the power further up the RPM......will make it worse down low

[ontheranch]

Nah I've had a turbo before (R32) and I know lag. Haha

It's like a small hesitation/stutter in low revs when I try and boot it. Just before the boost.

Sounds like I'll need to hook it up to some software.

Might try injector cleaner first. Any recommendations?

[Damo_R34]

i thought of stock ecu boost cut, but its at low revs/boost. hmm.

[Dohmar]

Nah I've had a turbo before (R32) and I know lag. Haha

It's like a small hesitation/stutter in low revs when I try and boot it. Just before the boost.

Oh. THAT...

thats too much fuel

its running so rich in thatpart of the map it burns slower rather than combusing quickly. and hence spewing soot out the back

i know it well atm (dont even ask) but if u take it to boostworx they can fix it, even on NA

-D

[ontheranch]

I don't know about the soot but I can't see it when I'm driving.

Do they just tune it or replace something?..

People always talk about knock sensors on WRXs, oh I have so much to learn becoming a Rexowna

and the forums arnt half as helpful as here.

[Damo_R34]

lol,

SAU:Yes Penny, so therefore you can see from my long equation that a standard vehicle does not require an injector upgrade.

WRXOC: MY goooooooooooooood bro, r they genuine vault chromies? You put Wanlis on coz they are cheap? i hear ya bro, need cash for my new gold necklace and autosalon entry fee.

/stereotype

[Dohmar]

I don't know about the soot but I can't see it when I'm driving.

Do they just tune it or replace something?..

People always talk about knock sensors on WRXs, oh I have so much to learn becoming a Rexowna

and the forums arnt half as helpful as here.

knock is something u get when ur standing on a serco bus next to a fat bastard

every engine knocks under poor environmental circumstances, provided the ecu has been taught to compensate

dunno who is the wrx tuner of choice in adelaide

sorry

-D

[ontheranch]

The Rex forums I have gone to are pretty quiet... It's not much of a community from what I can see.

I'll give S&J a call tomorrow and have a chat.

Thanks for the advice and stuff. Hope it's nothing serious. It runs awesome besides that dam Split second hesitation.

[SLED]

I think Sean from S&J Auto (WRX Shop) tunes at Brett Wests shop.

I had a Rex, can't tune the stock ECU (self learning) I also had issues with AFM & exhaust sensor sending wrong signals back to the ECU.

S&J or a tune shop should be able to find a faulty part if any.