I would think the one that feeds both rails, meaning the fitting closest to the cp3?
PPE ported fuel fitting vs stock Pics.
- Thread starter speedy03
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I would think the one that feeds both rails, meaning the fitting closest to the cp3?
Mine is also drilled sense 05 with no problem. Mine is drilled a little more then .90 though. Passanger and drive side is both done on mine
Another thread was going on that debate....the LB7 one is already bigger, "25000th is the measurement on the stock 01 lb7 orifice." (thanks Simon)
And Dale....GM only ever does things to perform to their maximum output....not ours
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so is this something that needs to be done with a lift pump. i mean how big of a gain are we talking about. and why would you only do one side
PM Mike if he doesnt find this and answer, I believe he was playing around with his fuel rail and cp3 as recently as yesterday, I bet he can give you all kinds of info on it.
Rail inlet fitting is bigger on a lb7,Its not the fitting that is the restriction on the LB7
ok if the fitting isnt the restriction then im guessing the FPRV is going to be the restriction?
Jared
Jared
Two lly ported ( drilled ) fittings would be better than the stock rail to pipe adapters. According to Simon, which I know now to be correct, the hole is very small on each fitting to each rail on the LB7. I have taken my rail apart to give Simon the size I currently run. He has the drill size, I don't cuz I'm at work. Just drill your two fittings, way faster. My hole size, if memory serves me, is .140 or so.
My rail fittings had to be changed before I bought the truck, this is the only conclusion I can draw. I have not changed them.
driver side is .90 from PPE im drilling the pass side one to .60 as to what Dan said would be as big as he would drill that side.
You wouldn't happen to know why he gave these numbers would you? I've been running these sizes for probably a year and a half with no problems. I only removed to gauge them for size. Just wondering. Thanks
I think with the LB7 it would not count, Im meaning the LLY,LBZ,LMM, on the LB7 the sell new rails from ppe that are ported all the way thru the rails. He told me not to drill the pass side to .90 just to .60 so that the driver side rail can still hold and not drain to fast to the pass side rail.
The FPRV is a pop off valve and doesn't have flow through it until hits the " pop off point ". I would treat this valve the same as the valves on the lly, shim it. My valve has a .125 copper slug or plug between the distribution block and the FPRV it's self. I don't think this is a good idea, but well I was able to run it for 1 and half years as well. I didn't know this was installed but have since removed the plug and shimmed the valve instead.
I still fully believe the major restrictions to be the rail fittings and the FCA on the CP3. But that's just my opinion.
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Yes, I've done a few that way. Larry just wouldn't let me, he just had to have a ppe valve...
I see thanks, I guess maybe I should install another pressure sensor and see if I have an unbalance between the rails.