I have ordered deadbolt super16g and adviced to use at least 720cc injectors. Would someone please help to choose the right injectors to use with the PowerFC? What brand would be a good choice for a MY98 ? I have also read that bigger injectors makes some idling problem is that true?

 

knock knock knock !!

 

i would say 550cc would more than suffice....they should be able to provide enoug fuel for 400bhp give or take...

 

bigger injectors can have idle probs yeah.

 

I run 550s on a 2,5 with a pfc (99 turbo) I think it probably idles better now with the 550s than it ever did with the 2 litre and 400s. I brought mine online from avo in australia. as for 720s unless you are looking at over 400 horse power which means mega £££, then they are probably overkill. Having said that give a ring to whoever is mapping your pfc and see what they reccomend.

 

550s will be close to maxing out at 400 bhp unless you bump the fuel pressure.
I cannot tell you what make of injectors to get but if the car is properly mapped then there will be no idling issues.

 

As Harvey said, the modern injectors on a decent ECU do not have any idling problems.
I have run both 740's and 850's on my car and it ticks over like a std one, hot or cold.
I'm about to fit 1000cc units which are reported to improve idle over even a std size injector !

Andy

 

have either of you tried power enterprise injectors? i looked at 800cc ones from them that are supposedly dual port so act like 400cc on idle but open up on load?

 

Dual port usually just refers to the spray pattern. I use PE multi port 650's on the WRX and they will be fine for up to 500bhp

 

would you recommend the PE injectors then?

 

I've only tried the 650's so can't comment on the larger ones. Have a look on nasioc for more info ?

 

will do, thanks andy

 

I actually aim for 350 bhp and regarding to deadbolt this turbo makes 370 bhp. They say it is maxing out the 650cc injectors so thats why he suggested me to use at least 720cc or more. (Americans like the big things )

As far as i remember AndrewC has reported that he is maxing out the 550s with a 18G. The Super16G(590CFM) uses the same TD05H turbine wheel used in the TD05H-18G, but it has a slightly smaller compressor wheel. May be it is better to go with the PE 650s. Actually I was concerning about the collars and connectors so thats why I asked specific brand name but i think PEs comes with the connectors and collars.

Cheers
Cuneyt

 

I'm not aware of an off the shelf 650cc for a classic. Thats normally a new age top fed size.
For your application I would use the 740's or the new twin spray 800's if you want a true 'drop-in' set with no connector mods.

Andy

 

Sonica,


STi pink injectors are more than capable of supporting 350bhp, or even 370bhp, although fuel pressure may need to be increased. They can't, and don't flow anywhere near 550cc, even at much higher fuel pressures.

If they are maxing out 650cc injectors (500bhp capable !), on a 370bhp turbo, they either have a fuel supply, or mapping issue.

If you already have 440's, with raised fuel pressure, they should be good for very close to your 350bhp target.

Mark.

 

You've PM Andy.F

I have 380s at the moment so i need to upgrade the injectors obviously. What if i order 800cc instead of 550s? Should I really stay away from bigger injectors? I'm concerning about the driveability and looking for "drop-in" injectors.

Lastly, what should I expect from this setup? I dont know the octane rate of a shell optimax there but Shell has relased 100 octane V-Power Racing yesterday in Turkey so i'll be using that.

Apexi PowerFC
Deadbolt Super16G on the way
Injectors will be ordered shortly
80mm Invidia Downpipe
80mm Mandrel Bent Midpipe
Blitz Nur Spec R
STI8 Intercooler & Waterspray
STI8 Style Scoop hood
Samco IC hoses
Intercooler Splitter
Green Panel Filter
Walbro 255lp/h Fuel Pump

thanks for all the inputs so far

Cheers
Cuneyt

 

Sonica,

With that turbo. 550's are more than enough, and much easier to sort out for the MY98.

Andy will be able to supply them to you.


Mark.

 

Something not right here. I know from personal experience on several classic cars that 550cc injectors will support 400bhp or just over WITHOUT bumping the fuel pressure. 740cc s will give you head room and allow for future "developments". (Maxed out somewhere between 540-580 bhp subject to fuel pressure and fuel) These things are a natural occurrence when tuning, also known as project creep.

650 cc injectors will support over 480 bhp and 500 bhp with a little pressure increase.

Is somebody trying to have your trousers down??? or is there a missunderstanding.
I think 650 cc are top feed and not compatible with your rails.

 

just wondering .. lets say with only small mods like ...arc box filter, hks ssqv bov, custom made downpipe catless and tanabe cat back exhaust system...and now i'm planning to install a blitz r-fit fuel controller and sbc-id boost controller..how much more boost can i increase and are my fuel injectors, regulators and pumps already working at optimum capacity?? just how much horsepower can these injectors and pumps produce and handle? thanks a bunch to anyone who can give me some advice

 

Depends what model and what model-year Smeegen. Check whether your fuel controller gives you IDC (injector duty cycle) values - it's normally a percentage. I wouldn't regularly run more than 90%....unless it's on my own car

 

As Richard says you need to find out your existing IDCs on full power.
What car is it and what injectors?
On your existing set up you may have very little head room with your O/E fuel pump so it would be prudent to start your mods there.

 

My '02 WRX's IDC was hitting 98% with the stock TD04 @ 232whp. I am running Sti 'pinks' with an APS S/R30 turbo (just slightly smaller than Jerry's super 16g) and have hit a max of 71% IDC @ 263whp. We installed a Deadbolt super 16g on my friends 95WRX wagon and he is running 740cc injectors. It has a bit of a rough idle but I kinda like it. The way I see it, your duty cycle will always be low and it would take a long, long time to out grow injectors that big. Most of us mere mortals will never need 740cc injectors or larger.

 

I have ordered 550cc Jecs as most of you suggested and fitted both 550cc and Super16 today. The duty cycle hitted to %79 @ 0.92 bar. I dont know what will happen if I increase the boost to 1.5 bar.

 

Sonica,

What AFR are you running, and have you checked your fuel pressure ?

Mark.

 

As Mark suggests, I would run these injectors at 4.0 bar differential and up to mid 90's IDC in the winter as this is as high as they will peak, the less dense air in Summer will result in lower IDC's.

Andy

 

Thanks
I'm using stock fuel regulator and I dont know the fuel pressure. I think it would be a good idea for me to order a new regulator. I'm running 10.9 at full boost at the moment but there is enough room to run 11.5s because EGTs never passes 1400F(760c).

The real real problem is the boost which i can not pass over 1.11 bar with the new turbo also (tried 1.3 today) and I'm about to eat my head.