Rep Power: 279

Okay so ive been trying to dyno my car and get it past the 7000 RPM mark, and once again today i failed even after upgrading from 440cc injectors to 650s and adding my walbro 255. It just doesnt want to push enough fuel. I maxed out the duty cycle of my 650's and they should be good to 500hp. im pushin 252 right now. and the Fuel pump should be pushing up to 500 hp as well. So im thinking its my intank fuel pressure regulator holding me back. And i have a feeling i need to just scrap it, and go return system with an ajustable FPR. Does this sound like it could be the problem? Or am i just imagining things?

 
Rep Power: 0

I don't know all the Honda speak yet but are you saying you have a 255 Liter Walboro pump? When I ran Buicks we could go high 10's in a 3800 Lb. car with it no problems. That's about 500-600 HP maybe just a little more. Doubt that is your problem. As to the injectors I can't relate the cc value as we always used Lbs. For us a 60-72 Lb injector would fuel that much power and still be in the 60-70% duty cycle range. How is your fuel table set up? Are you sure you are getting the right levels throughout? If you have a bad regulator that could for sure be a problem and also are the lines big enough to do the job? Do you have a gauge for fuel pressure to see what it is doing? Is it dropping off or increasing as you make your pulls? Do you have an EGT to see if it is really lean or a false lean? How about a WBO2 sensor?

 
Rep Power: 305

andy's running a simular setup to you, pm him and see what he has to say about it. I do believe he is running the stock regulator, perhaps disconnect the ground from it?

 
Rep Power: 279

1) my fuel table is set up using k-pro? Dont know what cha mean
2) Im not sure cause i think i have week pressure.
3) Im using the stock lines which is why im thinking about makeing a return system
4) Dont have a gaudge, dont even know where to hook on up
5/6) I know it was leaning out when we hit 7000 cause were using the wideband on the dyno.

 
Rep Power: 350

You're running a k series, right?
A guy I know in Houston has an a2 turbo with no return line running 500whp on his turbo setup. Your injectors are big enough, your fuel lines are big enough, your pump is big enough. Your regulator is set at 45 psi static. I made 247 whp on 440's at 80% duty cycle. It's hard for me to guess at what it is, without being able to see it in person man....Double check your hoses on your pump and make sure you don't have one of them not tight enough...that could be the culprit.....in fact, I'd go over all of my fuel lines and double check everything....
It may be your tuner, man, if he doesn't know how to use kpro, he may not be working the injectors probably....it sounds to me like it's something with your duty cycle....

But yeah, throw a gauge on it and check your pressure, although I doubt that's the culprit. Find another tuner and see if they can figure out your fuel tables. EMS can really throw everything off if they aren't set right.

The only other thing I could think would be the lines aren't able to flow enough fuel but why would mine be able to and yours not?

 
Rep Power: 279

This is seriously what is puzzling me. Yeah im running a k series. And the only think i did was install the new fuel pump and injectors. Ive been going threw everything checking and re-checking, Itjust doesnt want to go above 7000 RPMs without leaning out. I know Steven Church is tunning my car, and he works with hondata. Infact every wed Hondata comes to his shop and does R&D work there. Soooo i know he knows how to tune. The only think i can think of thats causing the problem is the intank regulator. The injectors want 48.6psi to run correctly... So im thinking im going to have to scrap the intank and do a return style system so i can up the pressure. I know i shoulnd have maxed out the 650's theres no way.

 
Rep Power: 0

Need a gauge to know what is going on or its all a guessing game. Can you free flow the fuel line at the front somehow?

 
Rep Power: 279

yeah that shouldnt be a problem