i've seen a couple lb7 trucks listing they have an lbz cp3 for it's higher press. is this a direct swap ? my stock pump is having trouble keeping up and a friend works at the local dealer. my truck is still under warranty so if i buy an lbz pump he'll put it in and get paid and give me the lb7 pump. i've done several lb7 replacements but, 1 why do work i don't have to and 2, i will get the lb7 pump to sell on ebay or something.

Believe it is a direct replacement, one is just designed to flow more.

Pardon my ignorance...What is the CP3?
Also do you know where to get a manual on the DMAX?

While not disagreeing with dieselson, I do not think u can "directly" swap these over. Reason being, I attempted this last year and after talking to eric he said its not a direct replacement bc of something on the back of the pump. He said it could be done, just have to mod it some to make it work. I may have my information mixed up some so just take it for what its worth. I had my truck torn down ready to swap and well, ended up staying stock.
Josh

cp3 is the high pressure fuel injection pump. It takes the fuel from tank, applies great pressure to it and sends it to the rails to be injected through the injectors. Thats in a nutshell of course. It can be referred to as the "injection pump" as well.

Its NOT to be confused with what some call "lift pumps" or "fuel pumps" as those are fuel pumps added to the fuel line between the tank and the the CP3. Without these, the CP3 sucks (yes in vaccum) the fuel all the way from the tank. As you may guess, the lift pumps are a welcome hand to the CP3 and lifts some of the "load" from it and allows it to focus on its job - pump high pressure fuel to the engine.

Hope that helps a little.



One question on I have on the topic is the fitment and switch of the LB7 FPR on the LBZ. Is there any issue there? I've heard of loping and idling troubles in this regard. Although it could have been due to using the LBZ FPR as well. Can't fully remember.


C-ya

Thanks for the quick replies!!
Helps alot!!

josh2002cc, who's eric can u or i contact him on this?

josh2002cc, who's eric can u or i contact him on this?

I'm going to assume he is talking about Eric Merchant of Merchant Automotive. He is a vendor here and goes by the screen name of "dmaxallitech". ;)


C-ya

IIRC there is only about $6 in actual cost difference between an LB7 and LBZ CP3. I have been told that the LBZ CP3 flows about 8% more.

I do not know if they are interchangeable without modification. If I had to guess I would say yes. I would think if modiffication is required, it would be minor.

IIRC the LBZ CP3 is rated to flow 115 mm3, and the LB7/LLY CP3 is rated for 110 mm3. Fuel pressure regulators are different between the pumps.

Im in the middle of the swap right now. From what i understand (and hope) its a direct replacement. The loping from what ive heard also depends on your lift pump and how much it pushes at an idle. I guess ill find out.:o:

-Rob-

Keep me informed please, I would love to know the outcome.

Im in the middle of the swap right now. From what i understand (and hope) its a direct replacement. The loping from what ive heard also depends on your lift pump and how much it pushes at an idle. I guess ill find out.:o:

-Rob-


The Fuel Pressure regulator is different and the LBZ FPR will cause a lope at idle on an LB7

The Fuel Pressure regulator is different and the LBZ FPR will cause a lope at idle on an LB7

Yeah i know, but it wont lope too badly with a lift pump that has low pressure at an idle, im running superdiesels, which has no pressure at an idle. You can also mess with tuning and make it quit.

-Rob-

I think it can be done.........;)

Just takes a little tweaking to make it happy...........:D

T:cool: NY

is it worth the efforts ? or should i just put the lb7 pump in it. i'd rather not put dual fuellers on it, seems like that leads to short rods and more money. how much power can i make with 1 stock pump?

You can make enough power with one CP3 to shorten the rods. If you want to keep a good life for the engine keep the power down around 500RWHp above that your playing with fire.

thanks i think i'm over that now with drugs !! anyone know the average price for rods and pistons ?

;) i think it can be done.........;) just takes a little tweaking to make it happy...........:d t:cool: ny

thanks i think i'm over that now with drugs !! anyone know the average price for rods and pistons ?


http://www.ttspowersystems.com/GM_Diesel_engine.html

thanks i think i'm over that now with drugs !! anyone know the average price for rods and pistons ?

I think you can find what you need here as well.

www.socaldiesel.com (http://www.socaldiesel.com)

T;) NY

If you need help tuning an LBZ CP3 on an LB7 contact me here via PM.

So did this change ever happen? If so, results?

So did this change ever happen? If so, results?


Maybe,

;)

Now Tony, Why the secrets??? :rippedhan

Now Tony, Why the secrets??? :rippedhan

There is no secret, it has been done, in fact it has been running on a truck flawlessly for 5 months now...........:eek:

I know the truck is red, and a crew cab, other than that I can't say...........:D

The Fuel Pressure regulator is different and the LBZ FPR will cause a lope at idle on an LB7

Mine doesn't lope with 9 psi fuel pressure at idle..........:cool:

Mine lopes with this mod. It is a direct bolt in and plug in . Sometimes it lopes bad, sometimes it's barely noticeable. As soon as sledpulling season is over I will send the tuner off and get it fixed.

Mine doesn't lope with 9 psi fuel pressure at idle..........:cool:
Tony did you see a big difference with the LBZ cp3? I don't want make anymore holes in my block like I did in February, but a little more won't hurt I hope. Also have you finished your testing to find anymore hp and tq. in our LB7's?

Tony did you see a big difference with the LBZ cp3? I don't want make anymore holes in my block like I did in February, but a little more won't hurt I hope. Also have you finished your testing to find anymore hp and tq. in our LB7's?

It definitely picked up HP with the new pump, it also pulls really strong on the top end, but unfortunately I have not made it back to the track yet to compare times, that won't happen until October 26th.

I'll know then how much better it is doing, until then it's just a SOTP-ometer guess.

;)

Mine lopes with this mod. It is a direct bolt in and plug in . Sometimes it lopes bad, sometimes it's barely noticeable. As soon as sledpulling season is over I will send the tuner off and get it fixed.


it was sure loping when i was behind you in line at scheids i was curious why. Thought it was the tune.