Getting dyno tuned and noticed that my car started getting lean around 735hp on a DYNOCOMM dyno. Which is weird because i thought the br double pumpers on modded 255 were good for 800+ from what i have read in previous threads. Am i really going to need to upgrade my pumps already or even add a 3rd inline pump? Please any advice is greatly appreciated at this point. Willing to try anything before i spend big $$ on new parts.

I have done the following
-swapped out to an aeromotive FPR and gauge (to test)
-changed the FPR boost reference to the the turbo
-re checked all my lines and fittings for leaks or kinks
-pulled out the hanger to inspect the pumps (everything was fine)
-cleaned out the injectors and fuel filters (not dirty at all)
-Fuel tested the e85
-checked that the hobbs switch was connected correctly

A Quick run down on the supporting mods:
-2.1L LR
-6466
-ID2000
-mini fuel lab fpr with gauge (43psi)
-8AN teflon feed
-6AN teflon return
AMS fuel rail
fuel pump rewire (10ga)
BR double pumper
modded 255s (second off hobbs switch 12lbs)
e85
stock ECU

 

Are you on stock feed/return lines? If so then that is your problem. Upgrade to 8/6. Also ask the shop if its a low reading or high reading dyno. You may be at the limits and not even know it.

 

Sorry I just noticed your on bigger lines. My bad.

Maybe the pumps are beginning to weaken.

 

they said it reads 5% lower than a dyno jet

 

Is the fuel pressure dropping off, have you actually looked at fuel pressure as the RPM climbs throughout the pull to see if that may be an issue?

 

^^^^^ this....

 

yes and it drops ~5psi

 

i also am having a boost spiking issue. Only have a 20lb spring in the waste gate but its shooting up around 30psi. I wonder if the two issues are related?

 

Do you log fuel pressure or is someone looking at the gauge? My gauge and sensor read about 9psi difference. Could be that your bfp is higher than what you really think. How did you set bro? You could turn the fpr all the way down, adjust the injector scaling for it and then see if that makes a difference...I just dunked on a dynocom and made more than that through stock lines, stock bfp but with DW301 pumps. I'm at 4700ft and touched 40lbs

 

You may be at the limits and not even know it.

 

Yea may be time to just upgrade one of the pumps to a 400.

 

it drops 5 psi from what?
80?

 

~76

43 base pressure and 33lbs of boost