Fueling & Injection Fuel Pumps | Injectors | Rails | Regulators | Tanks

Do I need to get bigger injectors?

Thread Tools
 
Search this Thread
 
Old Mar 9, 2003 | 04:19 PM
  #1  
TAGOES11S's Avatar
Thread Starter
Launching!
iTrader: (13)
 
Joined: May 2002
Posts: 238
Likes: 0
From: Niles, Michigan
Default Do I need to get bigger injectors?

I recently installed dual walbro intank pumps and my presure it sitting at 70lbs. Just wondering if its time to put pull the 26lb injectors and put in SVO 30lb injectors? Mods are as follows.

99 T/A MTI stage II heads, C2 cam, MTI programing, slp headers, Ls6 intake, Ported TB, FTRA, pulley, best so far 11.62 @ 118 TNT Kit - no times yet.
Reply
Old Mar 12, 2003 | 08:54 PM
  #2  
TAGOES11S's Avatar
Thread Starter
Launching!
iTrader: (13)
 
Joined: May 2002
Posts: 238
Likes: 0
From: Niles, Michigan
Default Re: Do I need to get bigger injectors?

ttt ????
Reply
Old Mar 13, 2003 | 04:31 PM
  #3  
last of the Z28's's Avatar
TECH Enthusiast
 
Joined: May 2002
Posts: 508
Likes: 0
From: rochester,ny
Default Re: Do I need to get bigger injectors?

ttt 4-u
Reply
Old Mar 26, 2003 | 09:50 AM
  #4  
Murdock's Avatar
TECH Apprentice
iTrader: (2)
 
Joined: Nov 2001
Posts: 377
Likes: 0
Default Re: Do I need to get bigger injectors?

I think I'm in a similar boat. I logged some runs last night and calculated >90% duty cycle.
<img border="0" alt="[shoot]" title="" src="graemlins/gr_guns.gif" /> 26lb

Have you logged your injector pulse widths?
Reply
Old Mar 26, 2003 | 10:39 AM
  #5  
Pro Stock John's Avatar
LS1Tech Co-Founder
20 Year Member
Community Influencer
iTrader: (34)
 
Joined: Nov 2001
Posts: 45,361
Likes: 1,792
From: Chicago, IL
Default Re: Do I need to get bigger injectors?

The smaller 26lb OEM injectors are on the small side for heads and cam, and if it were me I'd consider getting some 30lb injectors... I'd get Delphi, Bosch or Siemens before I'd get SVO's... Delphi's tend to have the best reputation out there.
Reply
Old Mar 26, 2003 | 01:34 PM
  #6  
Kylekay's Avatar
Teching In
 
Joined: Jun 2002
Posts: 27
Likes: 0
From: Pearland, Texas
Default Re: Do I need to get bigger injectors?

I am in the same boat as you, I have MTI S2 heads, C2 cam, LS6 intake, Mac headers and MTI LS1Edit tuning and I logged a pulse width of 23mS @ 6400 rpms, that works out to a duty cycle of 122% <img border="0" title="" alt="[Eek!]" src="gr_eek2.gif" /> My next mod will be new injectors about 42 lb/hr @ 58 psi.
Reply
Old Mar 26, 2003 | 01:39 PM
  #7  
JNorris's Avatar
Moderator
iTrader: (4)
 
Joined: Nov 2001
Posts: 2,074
Likes: 0
From: Montgomery, AL
Default Re: Do I need to get bigger injectors?

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by Kylekay:
<strong> I am in the same boat as you, I have MTI S2 heads, C2 cam, LS6 intake, Mac headers and MTI LS1Edit tuning and I logged a pulse width of 23mS @ 6400 rpms, that works out to a duty cycle of 122% <img border="0" title="" alt="[Eek!]" src="gr_eek2.gif" /> My next mod will be new injectors about 42 lb/hr @ 58 psi. </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Does your engine cutout/pop like you are hitting the rev limiter (but not as bad) when the injectors are operating at this level?

Thanks

John
Reply
Old Mar 26, 2003 | 04:59 PM
  #8  
Kylekay's Avatar
Teching In
 
Joined: Jun 2002
Posts: 27
Likes: 0
From: Pearland, Texas
Default Re: Do I need to get bigger injectors?

Not yet, but they are not designed to work at is level and will not last long. MTI said I'm not lean at top RPM so the injectors are handling it for now, however I have read that the injectors become inefficient over 100% dc.I have had a loss of power, (over time), that I am trying to fix, may be related but I think its probably the Mac cats.

<small>[ March 26, 2003, 05:03 PM: Message edited by: Kylekay ]</small>
Reply
LS1 Tech Stories

The Best V8 Stories One Small Block at Time

story-0

6 Gifts Neither Your Dad Nor Grad Will Shove Into the 'Trinket Drawer'

 Brett Foote
story-1

Topdon ONE vs. Artidiag 800 BT2: Which is the Diagnostic Tablet For You?

 Pouria Savadkouei
story-2

Gas Monkey Built a 6-Wheel Ferrari Testarossa With a Corvette LT4 Engine

 Verdad Gallardo
story-3

7 Most Reliable High-Performance Engines GM Has Ever Built

 Verdad Gallardo
story-4

Amazing '71 Camaro Restomod Is Modern Muscle Car Under the Skin

 Verdad Gallardo
story-5

6 Common C5 Corvette Failures and What's Involved In Repairing Them

 Pouria Savadkouei
story-6

Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph

 Verdad Gallardo
story-7

Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked

 Pouria Savadkouei
story-8

Top 10 Most Powerful Chevy Trucks Ever Made!

 
story-9

Hennessey's New Supercharged Silverado ZR2 Has 700 HP

 Verdad Gallardo
Old Mar 27, 2003 | 08:37 AM
  #9  
Murdock's Avatar
TECH Apprentice
iTrader: (2)
 
Joined: Nov 2001
Posts: 377
Likes: 0
Default Re: Do I need to get bigger injectors?

PSJ, I thought Bosch = SVO. No?
Reply
Old Mar 28, 2003 | 12:13 AM
  #10  
Camaroholic's Avatar
TECH Senior Member
iTrader: (1)
 
Joined: Nov 2001
Posts: 6,449
Likes: 1
From: Waco, TX
Default Re: Do I need to get bigger injectors?

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by Murdock:
<strong> PSJ, I thought Bosch = SVO. No? </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">You are correct. <img border="0" title="" alt="[Wink]" src="gr_images/icons/wink.gif" />

-Andrew
Reply
Old Mar 28, 2003 | 12:21 AM
  #11  
red ws6 99's Avatar
TECH Fanatic
 
Joined: Nov 2001
Posts: 1,190
Likes: 0
From: Las Cruces, NM
Default Re: Do I need to get bigger injectors?

Kylekay, just to let you know the injectors cant physically run more than 100 percent dc thats impossible. In fact your not supposed to run them over 80% If you are seeing 120 percent duty cycles then thats what the computer is commanding so you really need at least 20 percent more injector, but in reality you would want about 40% more. Of course this assumes you did the math correctly.

Gary
Reply




All times are GMT -5. The time now is 06:19 AM.

story-0
6 Gifts Neither Your Dad Nor Grad Will Shove Into the 'Trinket Drawer'

Don't get dad new socks or a grill brush this year.

By Brett Foote | 2026-06-04 18:13:20


VIEW MORE
story-1
Topdon ONE vs. Artidiag 800 BT2: Which is the Diagnostic Tablet For You?

Slideshow: We take a close look at the ONE and Artidiag 800BT2 diagnostic tools from Topdon and the reasons to buy one over the other.

By Pouria Savadkouei | 2026-05-28 11:05:11


VIEW MORE
story-2
Gas Monkey Built a 6-Wheel Ferrari Testarossa With a Corvette LT4 Engine

Slideshow: The controversial Ferrari F6 swaps its original flat-12 for a Corvette Z06-derived LT4 V8 and sends power to four rear wheels through a custom-built drivetrain.

By Verdad Gallardo | 2026-05-26 18:23:54


VIEW MORE
story-3
7 Most Reliable High-Performance Engines GM Has Ever Built

Slideshow:These GM engines didn't just make huge power, they survived abuse, boost, track days, and six-digit mileage with a reputation for refusing to quit.

By Verdad Gallardo | 2026-05-21 16:45:27


VIEW MORE
story-4
Amazing '71 Camaro Restomod Is Modern Muscle Car Under the Skin

Slideshow: This heavily modified 1971 Camaro mixes classic muscle car styling with a fifth-generation Camaro interior and modern LS3 power.

By Verdad Gallardo | 2026-05-12 18:06:42


VIEW MORE
story-5
6 Common C5 Corvette Failures and What's Involved In Repairing Them

Slideshow: From wobbling harmonic balancers to failed EBCMs, these are the issues that define long-term C5 ownership and what repairs typically involve.

By Pouria Savadkouei | 2026-05-07 18:44:57


VIEW MORE
story-6
Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph

Slideshow: A modern Camaro transformed into a retro icon, this limited-run "Bandit" build blends nostalgia with brute force in a way few revivals manage.

By Verdad Gallardo | 2026-04-21 13:57:02


VIEW MORE
story-7
Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked

Slideshow: Cadillac didn't just crash the high-performance luxury vehicle party, it showed up loud, supercharged, and occasionally a little unhinged...

By Pouria Savadkouei | 2026-04-16 10:05:15


VIEW MORE
story-8
Top 10 Most Powerful Chevy Trucks Ever Made!

Slideshow: Top ten most powerful Chevy trucks ever made

By | 2026-03-25 09:22:26


VIEW MORE
story-9
Hennessey's New Supercharged Silverado ZR2 Has 700 HP

Slideshow: Hennessey has turned the Silverado ZR2 into a 700-hp off-road monster with supercharged V8 power and a limited production run.

By Verdad Gallardo | 2026-03-24 18:57:52


VIEW MORE