i have a fully built DE with Greddy 18g twins. aeromotive 340 pump, cosworth rails, CJM FRS, ID1000cc injectors, aeromotive fuel regulator.
During the tuning process the fuel pressure is dropping off at 5500-6000rpms. Fuel pump is receiving correct voltage and thats as far as we went. Any reccommendations or personal experiences with same matter? Any help would be appreciated. If it helps, would using the Haltech Boost control have anything to do with it when raising boost this way?

 

How much boost

 

Wire upgrade for fuel pump?
How much hp before power drop?

 

15+psi it drops off, so when when fuel pressure drops so does PSI. around 450 before power started dropping. during the dyno pull, we checked voltage on pump and it was fine

 

Does boost drop off first or fuel pressure? Or at the same time?

 

same time i believe

 

or i suppose fuel pressure begins to drop so boost falls with it

 

If you have your FPR plumbed up correctly to a manifold vacuum source then fuel pressure is going to drop when boost drops. Fuel pressure should move at a 1:1 ratio with boost so if you base fuel pressure is say 43.5psi and you at 15psi of boost the total fuel pressure will be 58.5psi on the gauge. If you at 13psi of boost it would be at 56.5psi. If its not moving at a 1:1 ratio then you have a problem elsewhere

 

so in other words, if a boost leak was occuring it would start to fall then too?

 

Check your aeromotive regulator i have had two of them that leak that bad that u will run out of fuel due to there seats not been machined propely.

 

and how would i be able to tell if its not seating properly? any specific thing i should look for?

 

See if you boost and fuel pressure move together at a 1:1 ratio.

Or pressure test/smoke test it.

 

Just google aeromotive fuel reg leaking ,On one of the evo forums has pics of what to look for.
Does the engine lean out?

 

If your fuel and boost are dropping together it's likely a mechanical issue that's causing boost to drop. Usually if fuel pressure drops for no reason, your afrs skyrocket the first pull, then a pump or etc fails and you usually detonate on the next pull. Lol things just don't mysteriously follow suite.
It's just your FPR doing its job and following your boost leak.