Injector question???

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Jan 31, 2002 | 10:14 PM

onry

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Racer

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From: Overland Park Kansas

Injector question???

I'm running factory LT-4 injectors and turning 397 rwhp. I beleive I should increase my injector size but I'm unsure what to go to. 24, 30 or higher? I'm thinking a set of 24s or so. Aren't the factory LT-4 injectors 22lb? As is, the car runs rich and runs well so I believe the cylinders are being supplied with enough fuel but I'm sure the stock injectors are working their tails off. I'm also only running 45lbs of fuel pressure with the stock ones. Any suggestions on what fuel pressure to use with which injectors? Thanks in advance.

Jan 31, 2002 | 10:22 PM

mackeyred96

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From: Former NCM Drag Racing coordinator, National director Corvette Challenge Spring Hill, Tennessee: Whiting, New Jersey

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Re: Injector question??? (onry)

Before I'd worried about injectors I find a way to get that 60' time down.
I run 11.50s at the MPH.
I'D Go to #30s.

Jan 31, 2002 | 11:19 PM

onry

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From: Overland Park Kansas

Re: Injector question??? (mackeyred96)

The only time I've run it was on Michelin street tires at 35psi and I've also got Carerra coil overs set up for road racing on her. Not the best drag race set up. I'm still running the stock 3.45 rear end also. I'll try some #30s' and see how they do.

Jan 31, 2002 | 11:53 PM

GlockLT4

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From: Dallas TX

Re: Injector question??? (onry)

LT4's come with 3.5 gps (or 28#) injectors.. if you're going bigger, get 36#. LT1's come with 3.0 gps (or 24#) injectors.

[Modified by Glock'94, 5:50 AM 2/1/2002]

Feb 1, 2002 | 05:05 AM

AquaMetallic94LT1

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From: Hillsboro OR

Re: Injector question??? (onry)

Like to know more about your motor. 400 rwhp is about 460 at the crank. You could put the motor on a scanner and see what the injector pw is and then figure out the duty cycle. I think your probably okay for now. If you need to replace them, go to 30 lb FMS injectors. They are good for 32 lbs at the stock 45 psi fuel pressure.

Feb 1, 2002 | 08:45 PM

onry

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From: Overland Park Kansas

Re: Injector question??? (AquaMetallic94LT1)

How would I calculate the duty cycle once I get the pulse width? Excactly where should I check the pulse width? Idle, WOT, part throttle? What should the duty cycle be in order for it to be in spec with my motor? Thanks

Feb 1, 2002 | 09:35 PM

ChrisB

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From: College Station Tx

Re: Injector question??? (onry)

You should have enought injector unless you are turning over 7500 rpm or this is a blown/dry nitrous application. Actually your injector's are sized pretty much perfectly (with a little room for overhead).

Check your injector pulewidth (or duty cycle -however the scan tool reports it) at your max rpm (keep note of that rpm)

Feb 1, 2002 | 10:34 PM

onry

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From: Overland Park Kansas

Re: Injector question??? (ChrisB)

Quote:

Naturally asperated, and my max rpm is 7000. Although I do occasionally hit the 7200 rev limiter. :eek: My motor makes max hp at around 6800 but I usually just hit 7000 anyway.