Chevy and GMC Duramax Diesel Forum banner

1 - 11 of 11 Posts

·
Registered
Joined
·
10 Posts
Discussion Starter #1
I have a 04 lb7 newer engine has maybe 40k on it. When new engine was installed I had head studs, bd super max turbo, and 15% over brand new injectors. For now I'm running a garbage edge juice with attitude. I'm going to be installing a lift pump. Truck is hazing at idle and think it's the injectors. Have to run a balance test still. But my question is do I send them out for rebuild? Replace with new? Also is 15% over good or do I need to go bigger? I plan on having efi tuning done too.
 

·
Registered
Joined
·
916 Posts
Definitely do EFI live before you start messing with the injectors. EFI live vs. the juice with attitude will be night and day difference.
 

·
Registered
Joined
·
10 Posts
Discussion Starter #3
Efi live wont clear up the hazing at idle?
 

·
Registered
Joined
·
916 Posts
That can all be controlled and adjusted through EFI live by a custom tune from whoever you choose to go with compared to your juice with attitude that isn't oriented towards the air and fuel you are running in the truck.
 

·
Registered
Joined
·
10 Posts
Discussion Starter #5
Ok thank you I will definitely look into having that done. Definaltly cheaper than doing injectors again
 

·
Premium Member
Joined
·
9,817 Posts
If you do need injectors I would look into the new SAC injectors.
 
  • Like
Reactions: Durtynuby

·
Registered
Joined
·
10 Posts
Discussion Starter #7
Update just ran injector balance tests most were about 1.5-1.8 range. Had 1 that was 2.8-3.0. So injectors should be good?
 

·
Former GM Tech and parts
Joined
·
2,578 Posts
Balance rates only tell part of the story- to fully know injector health you need to see what the return fuel rates are from the injectors. Kind of a complicated test on an LB7. Generally the typical LB7 injector haze is due to the return rates being out of spec and not getting the correct amount of fuel into the cylinder, basically. Everyone says the 15% injectors (and up to 40% they say) don't need tuning. But to be fully efficient with bigger injectors, no matter what size, they need to be properly tuned to meter the correct amount of fuel and not have any haze.

A friend of mine has a triple turbo LB7 with dual pumps and 250%s in it. At an idle and just normal cruising it hazes all the time. Feed the beans to it and once it lights its clean.

My LB7 has 60%s in it, and a 63mm stock appearing cheetah. First start up cold and idling its got a little haze to it. Clean as can be when its warm.
 
  • Like
Reactions: tbear640

·
Registered
Joined
·
10 Posts
Discussion Starter #9
I will try and get proper tuning on it to start. Looking at efi live from kory Willis. Any other suggestions or recommendations
 

·
Former GM Tech and parts
Joined
·
2,578 Posts
I think that would be the best place to start. I've not run his tuning, but I would suggest finding a reputable tuner close to you. That way its easy to make changes if something is off or you decide to modify things. It has worked well for me that way
 

·
Registered
Joined
·
10 Posts
Discussion Starter #11
Update on this post. Installed air dog lift pump, and tunes from motor ops. Defiantly seems like the truck is happier now being tuned properly and has very little hazing at idle any more. Think that was the whole issue.
 
1 - 11 of 11 Posts
Top