I currently have this set up (383+t-trim) in my car with 42#injectors with an fmu. I upgraded my intake fuel pump to a 255 walbro. At 5500 rpms i'm seeing 10# of boost and the o2's start falling off. I changed the FMU at the fuel pressure jumped to 57psi still no big improvement. Does this sound right at 5500 rpms with 10 #s of boost. I plan to turn it up to 6500rpms. Does this sound like a job for the boost a pump, bigger injectors?????

What fuel pressure are you guys seeing? I was thinking of going with those 57# seimens injectors from racetronix. Do you guys think that might solve the problem?


Running out of solutions for this problem. Any ideas guys
GS355

 

Hello George, I wish I was far enough along to give you some input. I have the same fuel pump with the boost a pump. I think my opt has crapped out. I hope to get one today so I can put it in this weekend. Anyway ttt for ya.

 

I had 50# injectors with a Walbro intank 255 and ran out of fuel. I have a 383 with a15# ATI D1 although I see about 13# at most. I also started with 42# injectors and moved up to 50's and finally when I got the FAST, I bought 75s

I ran out of fuel and upgraded to a dual intank pump from Racetronix. I also got some 75# injectors from Racetronix.

No problems now.

I would say you either get a boost-a-pump or get the dual intank. the 42# injectors are going to be real close, maybe need 50's.

Just my humble opinion.

 

I run 42# injectors with the Dual intank pumps. It had no problem supporting 542 RWHP, but the fuel press with both pumps on is around 70 psi. This is with a completely stock fuel system.

Bill

 

I have been to their site many times lookin for some info on the dual pumps but never find anything, anyone have a price and are you all running the stock fuel lines?

 

Price was $500. You need to remove your sending unit from the tank and send it to the for modification. Yes I use an entire stock fuel system except the pumps.

 

Well guys, I'm stepping up to 57# Hi-Z injectors from racetronix. I hope this sovles my problem. As for the boost a pump, has any used the MSD boost pump. or is this the same peice you are talking about 97TA-WS6-Con.


George

 

I guess the stock lines are better than everyone thinks.

 

ronnie... autozone has complete lifetime warranty opti's for ~$130. i checked into it a couple weeks ago... the "warehouse" on cassat had one in stock.

 

Damn for $500 dollars you could have new braided lines and regulator and a good single pump. Are they dual 255 walbro's?

 

500 will NOT buy you a braided setup.. you will have nearly that just in fittings and crap

 

I just spent nearly $300 redoing the fuel system under the hood on my car, and this was jobber pricing on the parts!

 

I am currently running a custom twin intank setup made by Aggressive performance. Through stock lines the pumps have supplied enough fuel for 705 rwhp without any problems. I am also running 83 lb injectors.

 

Yup, twin Walboro 255's, all the big gauge wiring and weatherpack relays and fuses, and it plugged right in. Plus if this isn't enough a BAP will also plug right in. Its a deal and it took like 15 mins to hook up(not including the tank part)

Bill

 

Wow, I would have thought those 42's would have been enough for you with the fmu but I guess not. Good luck George, let me know if you need anything. TTT for you