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Devon
08-16-2012, 08:42 AM
Looking for what people generally drop rail pressure to on there big tune(max effort) with stock injectors and Lly pumps(23k). I drop to 21-20k towards the end of track. Is that ok on. 500+whp tune? Want to upgrade to a Lbz pump in the next few weeks anyways. What are other people with Lly pumps and stock injectors dropping rail to? I just replaced a injector and the return line on the driver side, and do far the trucks running strong. Just wondering if 20-21k is ok territory.


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05chevy
08-16-2012, 09:01 AM
My max effort tune would demand 26k and drop to 20k on my 12.35 passes.

Chevy1925
08-16-2012, 09:03 AM
its ok, wont hurt nothin. your just "missing power" if your falling under desired rail.

GMC_2002_Dmax
08-16-2012, 09:34 AM
its ok, wont hurt nothin. your just "missing power" if your falling under desired rail.

Ok, if you say so ;)

Devon
08-16-2012, 09:43 AM
So still capable of 12's with the rail pressure I see


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S Phinney
08-16-2012, 10:10 AM
its ok, wont hurt nothin. your just "missing power" if your falling under desired rail.

Rail pressure puts exponentially more feel in so that much drop in pressure is a major difference. Sure nothing will be hurt mechanically but it could run better with less PW.

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Devon
08-16-2012, 10:24 AM
So maybe go down on pw a little?
I mean on the hot street I hold more than desired rail most of a wot run.

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Chevy1925
08-16-2012, 11:58 AM
Ok, if you say so ;)

damn right! :joker: :D :hug:.

Devon
08-16-2012, 03:54 PM
So am I good for 12's at 20-21k of rail or what? Lol I want a solid answer my trucks demanding 23,8xx and I get 21xxx and some drops to 20,000 towards end of track. Was going to do a Lbz pump earlier but decided just to fix the reg with a Lbz reg. had to do a injector and driver side return line as it would only hold 17k max on all tunes before. Now 1-4 will hold 24-25k except my race tune. Normal?


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05chevy
08-16-2012, 04:06 PM
Everyone of my 12 second passes. Rail has went from 26k demanded to 20k actual. So 12's is very possible

juddski88
08-16-2012, 04:08 PM
You might gain some ground with new c3s...

Devon
08-16-2012, 04:10 PM
You might gain some ground with new c3s...

Tim if I could get them replaced I would be in business.. I think that's the complete truth. I have the dough.


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GMC_2002_Dmax
08-16-2012, 04:38 PM
Here are some facts, my 2002 LB7/LBZ-CP3 will pull down to 18,500psi and still run 12.6's

I did a lot of track testing and although the LBZ/LMM trucks want as close to 26K as possible to run well, the LLY and LB7's are more forgiving.

Pressure is better, but sometimes they just like the extra fuel, especially when that fall air is crisp and dry

Devon
08-16-2012, 05:23 PM
Here are some facts, my 2002 LB7/LBZ-CP3 will pull down to 18,500psi and still run 12.6's

I did a lot of track testing and although the LBZ/LMM trucks want as close to 26K as possible to run well, the LLY and LB7's are more forgiving.

Pressure is better, but sometimes they just like the extra fuel, especially when that fall air is crisp and dry

And that's what I wanted to hear. Thanks tony


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