how far can my stock injectors take me?

87gnNV

New Member
Joined
Dec 30, 2001
I have ported heads and stock turbo. Im planning on running 22# will i still be ok? Thanks
 
I would have to say no because I ran 23# on the stock turbo with a stock untouched motor and ran a 12.2 @ 112 mph but I had those stock injectors totally maxed out running 50 psi of fuel pressure. I can't even imagine how lean they would be with ported heads. Do your motor a favor and play it safe and buy a set of at least 42.5# /hr injectors if you plan on keeping the stock turbo or if you plan on upgrading the turbo soon, get a set of 50# squirters and be done with it. I got the 50's and have never looked back. I have PLENTY of fueling for my combo.
 
It sounds like you have the EXACT same combo as me, I plan on upgrading to 009's ASAP. Need a scanner first though.
 
I don't see why anyone goes to any high impedance injector other than a 50 pounder. If you're going to upgrade, leave room and just don't crank the FP to the moon imho. It's not like the 50s have a terrible idle or anything. I guess I AM biased though, heh.
 
No you won't, and you shouldn't even try! Not with ported heads.

I would suggest 55lbs injectors. One of the guys I know on here recently went 11.90's at 113 with a stock turbo, 55lbs, ported heads, and pump gas (alcy injection) on DR's and ONLY 16psi of boost. When you have ported heads, the efficientcy of the turbo maxes out at lower psi. In other words, you'll prolly go faster at 15 psi than 22psi as long as the fuel is their, and you'll be much safer.

Maybe he'll shim in here. :cool:
 
Originally posted by Turbojorge
When you have ported heads, the efficientcy of the turbo maxes out at lower psi.

Do you think a larger turbo would change this to make it more effective at 22-24 lbs?
 
I have 2 friends (GN and a T)running 11's with Stock turbos, Stock IC, ported heads and Factory Injectors BUT I'm sure the injectors are static or close to it on the GN.
I just wouldn't try it w/o keeping a VERY close eye on KR and I would not expect them to get you there unless they are in "new" shape..

Regards..
ks:cool:
 
Originally posted by Brian Mc
Do you think a larger turbo would change this to make it more effective at 22-24 lbs?


Yes. The bigger the turbo, the more efficient it is at higher boost.



:cool:
 
if your heads are well ported, I doubt you could get 24 lbs of boost out of a stock turbo.......boost=restriction.....if you could, it would be blowing nothing but hot air

as stated before, something like 16 lbs boost on the ported heads would make more power than 23 on stockers

the stock injectors are usually way done at 110 mph in a stock weight car (360-380 hp)

get some 50's at a minimum...if going with a bigger turbo, get the ecm modded and get 55's
 
Today's surprise is that the injectors go static with a stock chip.

To actually get enough fuel on hand to run other then static, takes a big jump, in injector size, since your talking about having to drop to about 85% Duty Cycle to to get reliable injector operation. 50s *might* get you there, but 55s make it safe. Only down side is finding a chip guy that that can actually get them to work with your combo.

So you wind up with having to do signifigantly larger injectors, and then need to be able to fine tune things, so that means a ME or Translator Plus.

If you like doing headgaskets, then 36s can be made to go fast static until the headgasket lets go, or stay real mild in what you do timing wise.
 
Totally agree with azgn ... I did it back in the early 90s. Basically the turbo was all done at 19# of boost. Even with the WG puck wired shut it would only barely squeak above 19#.

I had stock injectors, a seventh injector, ported heads and really mild cam (200/200). The car went 12.001 (It was KILLING ME that I couldn't get an 11.999! :)) @ 113.

The bottom end was killer too (1.54 short times on the stock D5!). However, the poor turbo was maxed out very early in the run.
 
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