Fuel pressure drop under boost..
 

Is fuel pressure drop under boost normal? I video recorded a couple pulls the other night and as my boost got above 6lbs fuel pressure started dropping but wide band was normal.

Sent from my SM-G960U using Tapatalk

No. Thats a sign that you need more fuel pump. Afr didnt change because your inj duty cycle went through the roof to compensate. Running your injectors over 100% wont last long. Recommended you dont go past 80%.

What is your fuel system?

The Fuel pump control module in the SS has fuel pressure set to 58, until your rpms rise, then its programmed to drop to 48. You can change the tune to demand 58 all the way, but most likely you’ll need more pump.

ZL1 pump

Sent from my SM-G960U using Tapatalk

When I was tuned, wot and full boost injectors were only 40% duty cycle. But I do not know what the fuel pressure was.

Sent from my SM-G960U using Tapatalk

Zl1 pump with a programmed fpcm should be good to a little over 600whp. Has your fpcm been programmed or did you buy a pre programmed one like jannetty sells?

My car come factory with a ZL1 fuel pump and whatever the tuner has done. And I was told 700whp was max on a ZL1 fuel pump on 93.

Sent from my SM-G960U using Tapatalk

Not unless he at least installed a BAP. What's the fuel pressure dropping to? You don't want to see any fuel pressure drop.

58 psi then drops to 50 psi

Sent from my SM-G960U using Tapatalk

Sounds like the FPCM was not tuned.

Ok, how do I go about doing that?
Getting the fpcm tuned.

Sent from my SM-G960U using Tapatalk

Greenhornet2 thanks, Jannetty sells a pretuned one for $199 probably best and fastest option.

Sent from my SM-G960U using Tapatalk

Yes, that's what i used. You may want a new tuner they don't seem to know what they are doing too well.

if you get an auxiliary pump, will your FCPM for the ZL1 pump still need to be adjusted?