I've had a Stage II HRC kit for a couple years now, just got done installing 8:5:1 pistons, and Crower billet rods. My problem is I can't get the fuel pressure beyond 100psi, when the manual calls for (if i remember correctly) 105-115psi at 7psi of boost.
I have an air/fuel meter that shows nothing at wide open throttle, leaning out like a champ at 8psi. I rewired the fuel pump with 10gauge directly to the battery, new fuel filter, replaced oxygen sensors, and still running lean. I'm gettin pissed. What is really strange is that when I first installed the kit, the fuel only went to 100psi, BUT the air/fuel gauge read rich at WOT like it was supposed to (and ran 10 times better than it does now) so I let the discrepency slide. I can only think of two possible causes, the fuel pressure regulator is faulty, or the fuel mapper "gizmo" that HRC provided isn't working right. Either way, how would I find out??

I would also like to know, when you guys set up the FPR, how much PSI did your pumps output? Did it go to like 125psi, and then you have to regulate it down, or did you end up like I did with adjusting the FPR to basically let the pump push what it could? Any help would be appreciated...

A couple of comments/questions...

One, you may want to examine your vacuum lines. As the FPR works off of the signal your vacuum lines send, it needs a particular amount of vacuum actually sent so that the FPR can send a corresponding amount of fuel.

Second, you are using the HRC inline fuel pump, right?

Last, since I'm using both an the HRC inline AND the walbro 255-HP, I have a tough time getting it UNDER 120 lbs of fuel pressure. That's right, I have the exact opposite problem as you. Therefore, I now have an S-AFC that I haven't installed yet to better tune my fuel system.


Jason
98' Eagle Talon ESi-T
Mitsu Super 16g Turbo(HRC)/Custom FMIC


http://springfielddsm.homestead.com/JasonsPics.html

_____________________________________
Jason ESi-T

04' BMW 325Ci
91' Nissan 240SX
98' Eagle Talon ESi (sold)

Would an SAFC and bigger inectors help? I would think that the biggest benefit of building your engine is to up the boost. You would need larger injectors anyway, so fuel pressure isn't as important. Just something to look into.

-Jeff
1999 Mitsubishi Eclipse GS-T'd

http://gs.dsmpower.com

I had a similar outcome with my HRC stage II kit; however, I didn't utilize the inline fuel pump, and instead, installed a Buschur in-tank. From that setup, the most pressure I got out of the intank was about 95 psi at WOT--that's with the fuel pressure turned all the way up!

Then, I replaced our stock 235cc injectors with 370cc's, and leaned it out with an Apexi S-AFC. Now, my WOT fuel pressure is around 65 psi and my fuel system is running RICH at WOT. So, I'll have to do some more fine tuning, and I'm also waiting to get it dyno tuned or by someone who's very knowledgeable. Until then I'll continue to run on the rich side, just to be safe.

I guess my point is, if you didn't use HRC's inline pump, then all you'll get from the intank is about 90-95 psi. Either install an inline fuel pump or get bigger injectors, along with an AFC to lean them out a little. From the posts within this forum, Jason ESi-T seems to have one the better fuel system setups. I hope this helps a little.

Later,

Fly1
1998 Eclipse GS
HRC stage 2 turbo system

___________
Kon C

"Sometimes, a man has to do what a man has to do."

well, Thanks for the compliment, fly1, butI would of course prefer to go the bigger injector like you.

I'm always looking for the safest and most bargain methods with everything it seems. In my plans, I do hoep to get some larger sized injectors.

A question though for you, fly1: why did you choose to go with 370's vs. 440's? Better low end and idle quality? (just guesses)

I'm sure there's not a whole lot of difference between the 370's and 440's, but I'm all for getting the best.


Jason
98' Eagle Talon ESi-T
Mitsu Super 16g Turbo(HRC)/Custom FMIC


http://springfielddsm.homestead.com/JasonsPics.html

_____________________________________
Jason ESi-T

04' BMW 325Ci
91' Nissan 240SX
98' Eagle Talon ESi (sold)

Jason, to answer your question about the 370cc's, I went with it because I think it allows a real smooth idle. My car still idles almost like-stock. Plus, I also think it might help with lower end torque. When compared to the 400cc's there isn't much difference, but since I'm only running 8 psi of boost, I feel that the 370cc's should be sufficient.

Besides, I believe that the 370cc's should be able to supply enough fuel to support 8-12 psi boost, and that going with injectors that's bigger just requires too much leaning out with the S-AFC. I think the S-AFC's a wonderful controller and, I didn't want to "stretch" it's limits (keeping it safe) Since I don't have upgraded internals yet, I'll not boost more than 8 psi.

After I get upgraded internals, I will probably go with 550-620cc's, if I could afford to get HRC's Accel DFI system and, boosting at 15 psi on pump gas. I know this isn't really a good, scientific explanation for going with the 370cc's, but I've spoken with quite a few DSMers and they thought that's all I'd need for now. Later.


Fly1
1998 Eclipse GS
HRC stage 2 turbo system

___________
Kon C

"Sometimes, a man has to do what a man has to do."

Just to clarify, yes I am using the HRC inline pump. My immediate solution is to up the voltage to the pump till it outputs my needs, probably around 14v-16v. Kenny-Bell makes an adjustable voltage regulator for fuel pumps, you would be shocked at what they do with just upping stock pumps a few volts (nearly double the ouput). Though Kenny-Bell is charging 200 bucks, which is out of the question. Luckily I have electronic people at my work designing one for me since DC to DC step-up transformer is not nearly as easy as I thought. The parts to make it will be around 30bucks. If anybody else is interested Ill post a link to the circuit diagram and parts list when its done.
I understand that nearly doubling a pumps output with higher voltage is probably going to lessen the life of the pump, but I only need a tad more.
As for the injectors, of course that would be the optimal thing to do, but thats roughly another $1000 for an AFC and the injectors, and probably more cause Ill need to get electronic timing retard setup to compensate. The new rods and pistons + labor tapped me out for while..
Thanx for the replies, though....if all else fails, I guess a better in-tank pump would do the job
And for all who read this, if your air/fuel doesnt read rich at WOT, you'll be replacing pistons like I did..... lataz