Was-Injectors pros and cons, now 300whp with my mods?

[SJCoruja]

Ok, I have done tons of searching and spoken to several of you when I could about this. I did want to open it up one more time in general to compile thoughts and figure out what to do before I get tuned on Tuesday. What are the real pros and cons of injectors? I have seen mulitple cases saying they are absolutely needed for safety and also allow a greater opportunity to make more power. On the other hand, I have seen multiple threads that they are overkill on stock turbo and will actually make the car run bad at low RPMs. Help me out! :)

[evo_dadi]

hmm actually no cons that i can think off not unless you get 1000cc's :shock: :lol: if youre not planning on doing much stock will be okay,but once you start going for more power adders like cams and upping the boost bigger injectors are a must.

[GokuSSJ4]

a car properly tune shouldn't have any problems. the cons behind it is either you will need a piggy back, stand alone or a flash to control the injectors.. if for some reason you try to use them on a stock ecu (no flash)
several of the socal peeps use 720cc with the help of the safc and have 0 problems what so ever... depeding how aggressive and how much boost you plan to run with your set up, that will determine the amount of mpg that you will get from using bigger injectors...

[L84AD8]

Pro's=Mo Powa
Con's=Gas $$$

8)

[earlyapex]

Pro's=Mo Powa
Con's=Gas $$$

8)

I get about 235 miles per 12 gallons (when I fill up), and that's driving the car like I stole it 70% of the time.

[L84AD8]

Pro's=Mo Powa
Con's=Gas $$$

8)

I get about 235 miles per 12 gallons (when I fill up), and that's driving the car like I stole it 70% of the time.

Damn that's pretty good. I'd get 210 on a good week... :( well all in-town driving stop and go. The best I got out of a full tank was 280 for all highway miles. :P

[evo_dadi]

man once i started modding i gave up counting how much mpg i get :P :lol:

[dohcvtec]

Pro's=Mo Powa
Con's=Gas $$$

8)

I get about 235 miles per 12 gallons (when I fill up), and that's driving the car like I stole it 70% of the time.
Thats better than I get, wtf mate? Time for CB toon? haha

[earlyapex]

Pro's=Mo Powa
Con's=Gas $$$

8)

I get about 235 miles per 12 gallons (when I fill up), and that's driving the car like I stole it 70% of the time.
Thats better than I get, wtf mate? Time for CB toon? haha

CB POWA! I get better mph in the winter than the summer. It's been pretty cold lately.

My fuel light comes on at about 11 gallons.

[crctslt]

hmm actually no cons that i can think off not unless you get 1000cc's :shock: :lol: if youre not planning on doing much stock will be okay,but once you start going for more power adders like cams and upping the boost bigger injectors are a must.

There's something wrong with 1000's? 8)

[evo_dadi]

hmm actually no cons that i can think off not unless you get 1000cc's :shock: :lol: if youre not planning on doing much stock will be okay,but once you start going for more power adders like cams and upping the boost bigger injectors are a must.

There's something wrong with 1000's? 8)

on stock turbo's :lol: too damn big for it :lol:

[ez76]

It is not so much the size of the injector so much as its response time, and whether your ECU (or aftermarket computer) has been adjusted to compensate.

Any bigger-than-stock injector that takes a longer time to open or close (relative to the stock injector) is going to tend to misbehave a little more e.g. in low load or in throttle/load transitions i.e. you'll tend to run overrich.

I believe as the injector size goes up, so does its response time, and so it becomes more important to compensate for it somehow, for drivability.

[dohcvtec]

I get better mph in the winter than the summer. It's been pretty cold lately.

ooo, me likey more mph!! :) :lol:

[earlyapex]

I get better mph in the winter than the summer. It's been pretty cold lately.

ooo, me likey more mph!! :) :lol:

mpg bic!

[GokuSSJ4]

hmm actually no cons that i can think off not unless you get 1000cc's :shock: :lol: if youre not planning on doing much stock will be okay,but once you start going for more power adders like cams and upping the boost bigger injectors are a must.

There's something wrong with 1000's? 8)

on stock turbo's :lol: too damn big for it :lol:
not if you have an EMS :P since you can control such huge injector, just in case you decide to go with a bigger turbo in the future.

[warpspeed]

Pro's=Mo Powa
Con's=Gas $$$

8)

I think it should be:

Pro's= Mo Powa with a proper tune.
Con's=Lots of Speeding Ticket :lol:

[Jamie@WORKS]

Unless you're running out of fuel, you're not going to get more power out of injectors. The stock injectors are fine for anything using the stock turbo. In fact, we're still using stock injectors on most of our White Rabbit setups. We usually recommend installing them when you go significantly larger on the turbo (i.e. the Time Attack EVO is using 800cc injectors with the GT35/40R setup).

In addition to the cost of the injectors, you've also got to factor in the cost of the tune. It can add up, especially if you want to retain all the part-throttle driveability.

[earlyapex]

The stock injectors are fine for anything using the stock turbo.

Tell that to my 98% duty cycle logs.

80% now with 720's

[Mister_Pants]

For as much as you drive your car Matt I would keep the stock injectors until you really go crazy. Drivability is going to become an issue and on a car that isnt heavily modified. At this point you wont notice a power increase from injectors, and risking losing some drivability for greater margin of safety may not be worth it.

[SJCoruja]

Thanks for all the replies guys, and keep them coming. I realize I should have put my power mods that are in/are going in next week:

Xede (91 & 100 oct maps)
264/272 camshafts
Cam Gears
3" downpipe
Tubular O2 housing
Hi-flow Cat
Cat-back exhaust
Fuel pump
K&N drop in
10.5 hotside (possibly)
720cc injectors (the big debate)

[earlyapex]

At this point you wont notice a power increase from injectors, and risking losing some drivability for greater margin of safety may not be worth it.

My car drives fine... average 18-20mpg driving the crap out of it. EVO's idle perfectly normal with 720cc injectors, well... before you put cams in.

People that say larger injectors hurt drivability either have a crappy tune or a... well, a crappy tune

[dohcvtec]

Like Bryan said. If you're seeing 95% + duty cycles you will need larger injectors. Daily driveability will not be sacraficed going to a 720cc.

[leif]

Thanks for all the replies guys, and keep them coming. I realize I should have put my power mods that are in/are going in next week:

Xede (91 & 100 oct maps)
264/272 camshafts
Cam Gears
3" downpipe
Tubular O2 housing
Hi-flow Cat
Cat-back exhaust
Fuel pump
K&N drop in
10.5 hotside (possibly)
720cc injectors (the big debate)

leave the injectors out. you dont need them since shiv knows what he's doing.

[SJCoruja]

leave the injectors out. you dont need them since shiv knows what he's doing.

Agreed there, but still would like the security and to have them installed and ready to go for when I upgrade the turbo. I actually may skip the hotside and go with the TME instead.

[dohcvtec]

I actually may skip the hotside and go with the TME instead.
DO IT
:)

[Matz]

So are all 720cc injectors about the same? Would you be just as well off with Helix or Denso injectors?

[ez76]

So are all 720cc injectors about the same? Would you be just as well off with Helix or Denso injectors?

Not necessarily. Depending on the design they are going to differ in terms of response time and how well they hold their pattern and flow rate, as a function of fuel pressure and battery voltage. For example, as a rule, disc-metered injectors (e.g. AMS') are going to have faster response time than pintle-metered ("Denso"-type) injectors.

[earlyapex]

So are all 720cc injectors about the same? Would you be just as well off with Helix or Denso injectors?

All I know is the Helix 720cc's sure look alot like my Denso 720cc's. :wink:

[Evotech8]

I haven't heard anyone mention this yet, but does larger injectors (after tuned) affect emmisions??
In another words, does larger injector pass a smog test.

[Gruppe-S]

We have tested the Helix Denso 720cc without any drivability problem. The car idles like stock but with much more safety margin when in the upper rpm range. From my personal experience, an Evo with cams and stock turbo should upgrade its injectors to at least 660cc. You will not lose any mpg or stock injectors feel if the car is tuned properly. With that said, you will not need anything if you were to only to drive the Evo on the street like a grandma.

Thanks,
Tom

[SJCoruja]

OK, last question...can I hit 300whp safely if I don't throw in the hotside or TME? I am thinking no since I have a cat (but it is hiflow) and the 9.8 hotside.

[earlyapex]

OK, last question...can I hit 300whp safely if I don't throw in the hotside or TME? I am thinking no since I have a cat (but it is hiflow) and the 9.8 hotside.

Yea that is going to be tough with the 9.8 and a cat. You could probably get 275-280ish on the gruppe-s dyno

[SJCoruja]

Hmmm...will the 10.5 make enough of a difference, or will I need to do test pipe and hotside to hit the 300 mark with my mods.

Xede
264/272 cams
Cam gears
3" downpipe
Tubular O2 housing
Hi-flow cat
Cat-back exhaust
Fuel pump
720cc injectors
K&N drop in

[earlyapex]

Hmmm...will the 10.5 make enough of a difference, or will I need to do test pipe and hotside to hit the 300 mark with my mods.


Mark said he gained 25whp going to a 10.5 and a helix HFC.

But then again, Marshell is doing 290whp on the Vishnu dyno with a 9.8

[SJCoruja]

OK, hotside it is! Now I just have to find a vendor with a super-cool hooked up price that can get it done today or tomorrow. ;) <checking PMs>

[SJCoruja]

Damn me for not planning ahead more. Everyone local is out of hotsides. :(

Anyone looking for an excuse to upgrade to the TME, WR, or 20G that are on sale now? :)

[SJCoruja]

UPDATE: After giving up a portion of my spleen for overnight shipping, an extremely cool and responsive vendor back East is getting my hotside out today for tomorrow's install! I am going to keep my HFC in and not go test pipe, but I am still hoping to at least meet or beat 301whp/287wtq 91oct...a totally random number I made up as a goal. :twisted:

[earlyapex]

UPDATE: After giving up a portion of my spleen for overnight shipping, an extremely cool and responsive vendor back East is getting my hotside out today for tomorrow's install! I am going to keep my HFC in and not go test pipe, but I am still hoping to at least meet or beat 301whp/287wtq 91oct...a totally random number I made up as a goal. :twisted:

awesome, I look forward to seeing how the tubular 02 housing works!

What dyno and who is tuning it?

[SJCoruja]

awesome, I look forward to seeing how the tubular 02 housing works!

What dyno and who is tuning it?


Thanks! I am meeting up with the Vishnu crew at Full Function for the install of everything, then Shiv will be using their dyno to tune. I'll make sure to post everything up tomorrow night. :thumbsup:

[L84AD8]

awesome, I look forward to seeing how the tubular 02 housing works!

What dyno and who is tuning it?


Thanks! I am meeting up with the Vishnu crew at Full Function for the install of everything, then Shiv will be using their dyno to tune. I'll make sure to post everything up tomorrow night. :thumbsup:

Good luck and have fun! :wink: :P :peace:

[SJCoruja]

Well guys, today REALLY didn't go according to plan. Evo is in bad shape and I'm trying to get everything sorted out tomorrow. Got my fingers crossed though on a save-the-day from some local folks who've always been good to me. :)

[wilson1]

what happened, Matt?

[DRFTR8]

what happened, Matt?

i can just tell you that it didnt go the way he wanted... he is very upset and dissapointed

[missred]

what happened, Matt?

+1 :?