Hey guys, I searched and got some mixed results, i see some people running 720s with mods like mine and others who say its too big. Hoping for a guru to help me out.
I have an 03 with hks carbon ti, helix v.2 heatcoated downpipe, test pipe coming soon, hks rs intake, turbo xs blowoff valve (recirc), dejon tool mbc set at 20, and going to be tunning off an SAFCII or SAFC NEO. Based on those mods are 720s too big? If so what is the downside of running 720s as I do plan on eventually going to a slightly bigger turbo (perhaps a 9 20 g tme like the one sold on turbocharger.com)

 

You have no need for injectors with those mods while on the stock turbo. They should be fine when tuned by the SAFC as long as you know how to do it for both low and hi throttle. 720s aren't too big, but they are about as big as you want to go. They also will work when you get a 20g-9, but please don't get the 20g-9-6 from turbochargers.com. Make sure you get the 20g-9-5.

 

no, 720s are not too big, but u are maxing out pretty much what u need.

 

I was also thinking about going the Larger Injector Route , but was given mixed advice from different tuners I both trust.

I currently Have a set up that looks like this:
264's
K & N drop in
Helix TBE w test
Hallman MBC sitting at 1.8 bar
FP
and Custom Tuned By Dan Harman

I am sitting at 330 // 330 on 104 Octane Unleaded.

My power is low from what I understand. RRE made a comment stating that the Injector duty Cycle may be maxed and that is why the car isn't getting the most timing it could be. I have no freaking idea what the hell is going on and I prolly should have started a new thread.

 

Kilterman, at your level of mods and running high boost 24/7 without alky, I'd suggest injectors, personally - 660s, 680s, or 720s.

 

To the original poster- Getting bigger injectors would be a complete waste of money with the mods you have. Spend that money on something else.

 

Thats What RRE had stated aswell. Harman Said that I am getting the right amount of Fuel and that he doesn't remember me maxxing out the duty cycles of the injectors ( granted I was tuned 4 months ago , and I asked the question today) SO I don't know wtf to think and believe , tuners are like doctors. Both have excellent points and I will be at Harman Thursday to Do a run thru, now is the debate on when and if to get injectors

 

Well, the truth is you don't really need injectors on the stock turbo, but that doesn't mean you can't be near the edge of their utility, especially when running such high boost. Plus, if your tune isn't really lean and pulling out a lot of fuel, then your IJD is probably pretty high. I run high boost, too, but with alky, I have to pull out a TON of fuel, so my IJD stays down...

Is there a reason you haven't just gone with alky instead of spending so much on 104oct all the time? That would remove the injectors question, but if you only drive the car occasionally, then I suppose doing 104 all the time isn't an issue (if that's the case).

 

the gas is expensive yes but I am a safer than sorry type fellow and I look at alky like NOS , the risks out weigh the gains. I would rather pay the 4.79 a gallon for a weekend racer than risk a crummy or clogged Nozzle dilly. Plus With gas the way it is Race gas is almost a dollar more expensive than 91 here. I am cool with that.

 

Yea, $4.79 isn't much. It's $6.50/gal here. Also, the "risk" you refer to is not as much as you make it out to be. There are solutions that have failsafes, and there are solutions that set the tune so that the engine doesn't immediately give way if the alky fails.

Obviously, race gas has no risk in these terms, but the IJD could be an issue...

 

Yeah I got really lucky on the Gas issue. I thought you were Moving a while back ? Alky just isn't for me. Its prolly alot safer than I think as I have no first hand knowledge. At this point I am content with the Gas, plus checks dig the sweet smell of the Race Juice.

Also, whats your word on the IJD? I ain't worried but mixed results from two respectable tuners drives me nuts. Especially when I don't know to much in the Area and am looking for Guidence

 

You need to physically check it probably, then determine if that is too high for you and your safety concerns or not.

I also don't pay much attention to dyno numbers without verifying my power at the track. Your 330 could be great, bad, or average, but you won't know without trap speeds.

 

I understand completely the problem Is My weak *** clutch from a crummy driver :ahem: But in the real world I have never had an issue with beating "over powered " cars. My 330 ate a 400 supposed whp sti so I am but I am not worried about the numbers.

 

Btw, I did move to Colorado Springs. Browse the drag forum to see my sickening loss of power and resulting loss of ETs. I also did some Dynojet comparisons before and after, which show the massive loss of area under the curve.

 

Thats right I forgot you were moving to the high altitude of Colorado. Atleast you can swing by and see that monster that whats his face is building, 3240 is his screen name.