can you use an lly CP3 & regulator in an LB7 application? If no, why not?
Cross breeding
- Thread starter TNRGreene
- Start date
Yes I believe you can Todd. I believe all years are interchangeable... I just know the LB7 Regulator has a straight connection where as the LLY+ have the 90*
your fine 
super diesel
<<<< Under Pressure
Idle pressure will need to be adjusted but this is the same as using an LBZ,LMM reg in it. Lb7 and LLY pumps are the same critter. If you do, make sure you match up the ports on the suction pump on the back. These pumps need this unlike the LBZ and LMM pumps.
Running an LBZ pump in my LB7 as we speak. Regulator voltages were re-scaled and only get a hint of lope early on a cold start or really low fuel tank levels.
You will have to alter some plumbing due to the different regulator end. But if you put a LB7 regulator on the LLY pump, that problem goes away. If you can, use an LBZ/LMM pump, not an LLY. Price is similiar, but you get 8% more flow.
super diesel
<<<< Under Pressure
Pats correct. I use dual LBZ/LMM pumps with a set of my moded LB7 regs on them. If you use a LB7 reg make sure to get it moded. It is the most restrictive of all of them. The LLY is next but flows much more. The moded units will flow more than the pump can use.
Thanks all this is not for me it's for a guy that found me & asked
TTT. The truck is now running I saw it last night. It idles great as long as you don't touch the throttle. But if you do as soon as it revs & comes back down to idle it acts like you are unplugging the reg for 2 seconds and then plugging it right back in. Rescaling probably won't help that will it? Who has an answer :hug:
Is he running PPE tuning? My truck did that with an LBZ pump and PPE tuning. anyone elses tuning and it as fine.
No clue what tuning, he bought it used