I recently had a tuning session for my Vortech with 3.12 pulleys and 440cc injectors with Utec. I have the Walbro pump with TN fuel regulator mod. I seem to be running out of fuel above 6400rpm at 9psi. Everything else seems to be fine. The question is, I still can't adjust the fuel pressure even with the mod (up or down). The fuel pressure remains pretty constant at ~56 psi even in boost. Is there a way of just removing or bypassing the stock regulator? I can always upgrade the injectors and keep everything as is I guess. Thanks for everything Julian and sorry for having to make you wrench a bit .

 

yes.. I hade the same problem. Running real lean in high RPM. get a AAM basic fuel return system. Gets rid of the stock regulator and you will have all the fuel you want.

 

Damn I was really trying to avoid getting a return system lol. Another $550 drain in the wallet plus whatever the bigger injectors are going to cost me. Thanks for the input MUZZY.

 

Heres what came in my kit. Does it replace the stock regulator? I still need to go over the directions again.

 

I am assuming it comes with a rising rate fuel pressure regulator which would replace the stock one. I am just unsure how the connections go to the fuel pump in the tank to bypass the regulator. That o-ring is to replace the one when removing the fuel pump assembly behind the passenger side I would assume.

 

Do you have the dyno chart with A/F..?

 

Son of a *****!! I think im missing something... Heres there pic from the website.

 

open da lil white box. it looks like its all there.

 

White box is just the gauge.

 

anubyss, sorry for jacking your thread.

 

No problem NS 350GT . I won't be able to post the dyno charts until I get home tonight. After 6400, the a/f starts to climb above 12.

 

yea I was like WTF >< another $500 needed mod. but tell you what. it makes a world of difference. The stock regulator in the fuel pump assembly comes out and the return line takes its place. in the second picture. its the thing all the way to the right. and yes it comes with a rising rate regulator. you adjust it to give you more fuel per lb of boost.

also the 440 injectors are plenty. you dont need bigger ones.

what is stoping you from geting fuel was the stock regulator not the injectors.

easy install over all.

 

It looks like I just need a bit more fuel so 550cc injectors might not be necessary. I am going to order up the basic return line kit and see what the a/f does up top. Hopefully I can play around with Utec and do the minor tuning myself .

 

With out a boost referenced fuel pressure regulator the 56psi of fuel pressure you are seeing in the rail is reduced by what ever the boost pressure is in the manifold becasue the fuel pressure has to push against the boost pressure when the injector is open.

 

are you running a revup? if not is there any reason to be so concerned since the limiter on the 287 motor is at 6500rpm.

 

I have the limit set to 7100 with the AAM reflash. It's not just that, but also I really don't want to be at the limit for anything. Once I find out what the injector duty cycle is, I'll decid whether or not bigger injectors and necessary. I'd like for it to be around 80% duty cycle at max.

 

I have a rising rate fuel pressure regulator but it's either not working at all (won't let me turn the pressure up or down) or the stock regulator is interfering with it. So the best solution would be to just remove the stock regulator. I should have the AAM basic system by Friday so I can install it on Saturday.