Currently have a walbro 450 and precision 1200cc. Is this going to be enough for 550 on e85?

 

Based on my E85 setup i think youre going to be close on the 1200cc injectors. You should specify whether this 550 is based on Mustang / Dynojet

 

This would be on a dyno jet.

 

I don't think you are going to get to 550whp on E85 . I ran ID1300's and added a gallon of pump 93 each tank to bring the content to E70ish to give the injectors some headroom. I had a 450/267 pump with a boost a pump . A 450/274 has a higher pressure relief so that would also help. I made 500-530whp on E70ish on a dynojet .Important to note I only turned 7800-8000rpm. Higher rpm will need more fuel.

There was also an EFR 2.3 on ID1300's on E85 that was out of injector at 530whp years back.

You could move into a larger injector.
Increase base pressure
Lower content to E70 (If you are really going to run it hard I would add MS109 or C16 for octane)

 

Thanks for commenting Tim. I just know at my 460 DJ WHP on E85 running RC1000cc injectors, i have very little head room (high IDC). Really needed larger inj's for my tune but it still runs hard years later

 

You'll need Fuel Injector Clinic 1650 HiZ's to safely make that power.

 

I'm just going to echo what everyone else said. I was running FIC 1100s or whatever on E-85 and was pretty tapped out in the upper 400s. After a built motor, moving to a double pumper and an FP red, I went to the ID 1700x injectors and have plenty of headroom in the upper 500s. I don't have a log in front of me but if I remember right I'm in the upper 70s-low 80s IDC currently.

 

Thanks for the info everyone