GM Engine & Exhaust Performance EFI | GEN I/GEN II/GEN III/GEN IV Engines |Small Block | Big Block |

LQ4 fuel injector size?

Thread Tools
 
Search this Thread
 
Old May 11, 2005 | 08:11 PM
  #1  
Squirrelmaster's Avatar
Thread Starter
TECH Apprentice
iTrader: (2)
 
Joined: Oct 2003
Posts: 360
Likes: 0
From: MSP, MN
Default LQ4 fuel injector size?

Does anyone know the size of the stock LQ4 injectors? I've tried the search with every term I can think of, but with no luck. My 2001 HD has been throwing codes at me like crazy, so I took out the injectors to see if there was any water in the rails, and when I did, a bunch of sand came pouring out of the fuel rails (what can you expect from an ex-oil field truck ). So needless to say, I think the injectors are screwed. I cleaned them out as best I can, but I'm still getting a P0300 code, and so I'm hoping new injectors will fix the problem. Thanks for any help.

Tom
Reply
Old May 11, 2005 | 08:32 PM
  #2  
99Silver6.0's Avatar
TECH Veteran
iTrader: (1)
 
Joined: May 2002
Posts: 4,039
Likes: 1
From: Olathe, Kansas
Default

Originally Posted by Squirrelmaster
Does anyone know the size of the stock LQ4 injectors? I've tried the search with every term I can think of, but with no luck. My 2001 HD has been throwing codes at me like crazy, so I took out the injectors to see if there was any water in the rails, and when I did, a bunch of sand came pouring out of the fuel rails (what can you expect from an ex-oil field truck ). So needless to say, I think the injectors are screwed. I cleaned them out as best I can, but I'm still getting a P0300 code, and so I'm hoping new injectors will fix the problem. Thanks for any help.

Tom
24.7lb/hr.
Reply
Old May 11, 2005 | 10:10 PM
  #3  
Squirrelmaster's Avatar
Thread Starter
TECH Apprentice
iTrader: (2)
 
Joined: Oct 2003
Posts: 360
Likes: 0
From: MSP, MN
Default

Originally Posted by 99Silver5.3
24.7lb/hr.
Ok, thanks. I actually stumbled across one of your older posts that said that (guess I can't use the search very well ) and was going to confirm it when I saw your reply. I'm hoping to get some take-offs from someone who upgraded, but if that doesn't happen, does anyone know where I can get some comparable (read: no tuning required) ones from?

Tom
Reply
Old May 23, 2005 | 05:52 PM
  #4  
Steve Bryant's Avatar
LS1 Tech Veteran
iTrader: (1)
 
Joined: Oct 2003
Posts: 1,172
Likes: 0
From: Wichita, Ks
Default

The only way you can make an injector change and not change anything in tuning is to go with another 24.7 lb/hr injector. If you go with larger injectors, the injector flow rate will be off and your LTFT values will go very negative. You just can't go to bigger injectors to support more HP without changine the IFR to the new appropriate values. Unless, you go to a bigger cam and/or do some head porting or some type of power adder, you don't really need bigger injectors as your stock ones will support max HP of the engine and not exceed a duty cycle of about 80% .

Steve
Reply
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
rojeho
GMT 800 & Older GM General Discussion
4
Aug 8, 2015 07:20 PM
FlowmasterMufflers
Sponsor's Announcements, Sales, and Specials
0
Jul 30, 2015 05:03 PM
lsxmalibu
GM Parts Classifieds
2
Jul 29, 2015 07:08 AM
jrplz
GM Parts Classifieds
6
Jul 9, 2015 12:07 AM




All times are GMT -5. The time now is 07:54 AM.