CP3, FPR or tuning?

SteveFord

What's Next?
May 8, 2008
1,317
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Iowa
Pressures down a bit on that log for sure. I'd say if it isnt your cp3 than Id look at the return rates. Hurry up Tom, I was exspecting you to get into the 11's this year before its over lol!!! Honestly I do think you can if you can get this figured out!
 

TheBac

Why do I keep doing this?
Staff member
Apr 19, 2008
15,615
1,874
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Mid Michigan
Finally got the guts to go in and change a few things. Dropped maximums to 2400 pulse, 27* timing and 160 fuel pressure. All the multipliers in my race tune are the same as my stock tuning, so I left those alone (and wouldnt have known how to change them anyway). Running around today, the truck didnt seem to miss a beat.

I also have to clean the MAF and boost sensors and replace the fuel filter before Sunday. Thats for tomorrow.

Thanks again for all the help, Steve. We'll see what happens.
 

Operator1

Member
Nov 20, 2009
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16
NC
FWIW, my truck with 30 overs and 2700 pulse on the stock 193k mile pump was dropping rail pressure to 16-17k. Now with an lbz pump it only drops below 21k psi when it gets above 3600 rpm.

mispeeld with tapatalkz
 

ZeroGravity58

Well-known member
Mar 23, 2008
1,401
51
48
38
Maryland
With 30 overs and a stock pump in my old truck I would run a 2540 pulsewidth and it would hold around 20k. A 2700 pulsewidth is a touch to much to me.
 

TheBac

Why do I keep doing this?
Staff member
Apr 19, 2008
15,615
1,874
113
Mid Michigan
With the changes I made to timing, pressure and pulse, rail pressure came back up to 22500+ throughout my first runs today. I then put the old tune back in but lowered pulse to 2500 and rail was 20000-21000.

BUT, couldnt get 33lbs boost out of the turbo no matter what we did. Was only getting 23lbs on the gauge, so turned the Banks wastegate 5 turns (!!!) and only got it to 29lbs. Im going back to the stock wastegate with boost valve. Boost did stay up during shifts, but if Im going to lose 4lbs over the whole run, then its not worth it.
 

rcr1978

Active member
Apr 1, 2007
790
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28
Spring Creek, NV
I tried this also when I first put mine on, it does not work well this way because the your using 33psi to visually see the arm move on your turbo. I had to keep tightening until I got where I wanted (32psi) it takes very little arm movement to bleed off drive energy, more then likely not enough for you to see. Keep tightening it.
 

TrentNell

Finally underway !!!!!
Jul 7, 2008
7,543
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slc tuah
I tried this also when I first put mine on, it does not work well this way because the your using 33psi to visually see the arm move on your turbo. I had to keep tightening until I got where I wanted (32psi) it takes very little arm movement to bleed off drive energy, more then likely not enough for you to see. Keep tightening it.

X2 , the air pressure regulator wont be near accurate , that doesn't compensate for the 40-50 psi of drive pressure pushing on the valve , the only way to tune it is to keep cranking it down and test by running the truck , also considering putting a regulator in the boost hose that feeds it to control the boost pushing on the diaphragm .