DSP5 Tuning Problems

[BigTexas68]

I have installed the dsp5 in my lb7 and everything works. My problem is that my performance tunes drains the rails or pops the relief valve and the engine falls on its face at the end of second gear if I take off from a dead stop. It runs fine if you get going and roll into it. I used fuel,timing,base torque tables from my known good tunes from the stock operating system that work without any problems at all.

Is there something I need to be doing different working with the dsp system?

[BigTexas68]

Bump. Help please

Ok after trying to remove some fuel and put the base toque tables/tliq back to stock, I still have the same problem. I copied/pasted my #2 tune tables into #3 spot with everything identical and I still have the problem. The #2 works flawless in the #2 slot. I dont think it is fuel related. It actually feels like you turn the key off and on when this happens. But this happens under hard accelleration, 90%tp or more.

I have put the stock os back in with a single race tune and everything works good.

Garrett's DSP5 Tune hardwired_0002.tun

[Dmaxink]

If the reliefe valve popped open once...Tuning wont fix it. Shim or plug the valve...

[BigTexas68]

Can the relief valve be shimmed on an LB7? I have another block I can try. Its a little strange that I only have the problem with the dsp tuning and not the st6andard operating system. If the voltage from the switch was varying out of range would that cause any issues like this?

[WisconsinHick1]

I am actually running into the same issue. We are asking for 26000psi and at WOT I am seeing about 12000psi on average so I think I am pushing my relief valve open and loosing my rail pressure. You can shim it or block it but its not as easy as the newer models. You have to pull the relief valve out and add more washers or find a plug or some are taking out the banjo bolt and welding or plugging that in different ways.

[BigTexas68]

At first I thought it was the relief valve popping open but I have my doubts. Unless the DSP operating system ramps up quicker that the stock OS. I command a whole lot more fuel with the stock OS than I do with the DSP without any problems.
What about the in tank modifications? I have not done anything inside the tank. I think I have plenty of fuel going to the cp3. I have measured 5-6 quarts per minute after the filter.