After six very fun, problem free months of forced induction, I decided to hook up the fuel pressure gauge to the windsheild again and check what my fuel pressure is under WOT since the damn thing doesn't stay below 60 at idle. I hit 100-105 in every gear which is perfect, maybe a little rich for 6psi but better safe than sorry. This was when the idle was around 70-80psi, where it always is. I adjusted the idle back to 55 and got the same fuel pressure results under WOT, but of course, i started the car back up later and the idle pressure went up around 70-80psi again. So my question is, should i not worry about upgrading my fpr since it works great under boost or should i change it because of how it screws with my idle psi constantly. does the idle fuel pressure really even matter, except the fact that it might waste more gas??? i'm not sure so someone please tell me if it's alright or not. Thanx...




HRC Stage 2

Hhhhhhhhhhhhmmmmmmmmmm!
Mine does the same thing!!

I too was thing about upgrading the FPR

anyone know who makes the best?

Have you called HRC tech support? I think Bill has made it very clear that if in fact the FPR needs to be replaced, then they will gladly replace it.



Eric Madden

haha I wonder what fuel pressure I'll get if I get a gauge :P

damn thing has been running rich ever since I got the kit in there. like .98v and such. Stock pump plus Airtex Inline pump...

I just changed my oil and man it smelled like gasoline. I'm surprised my o2 sensor hasn't fouled yet!

>Have you called HRC tech support? I think Bill has made it
>very clear that if in fact the FPR needs to be replaced,
>then they will gladly replace it.


Yea, he said that on here also, I emailed them about a month ago with quotes of him saying they would replace. I wonder if they plan on emailing me back. 110 is way to high for 6psi. 110 is 10psi fuel pressure, see if you can get it to around 90 fuel pressure.

I just got the new HRC "billet" design, it *looks* very promising... gotta install it tonite and find out if it really works.

FYI- They dragged me thru a bunch of "troubleshooting" steps, (i've gone thru them all before, they didn't care- do it again) and saying it's very rare for the FPR itself to be bad... I finally just got tired of the call and they offered to sell it to me for $200 + shipping. They said they'll reverse the charge when I send my bad FPR back and they test it. (minus the shipping of course) x(

well dude, i got the new fpr and i thought it was bad when i warm up the car it would stay around 60-65psi and before that i would have set it to 53-55psi anyways i talked to bill and some peeps at tech and what they said is that let it warm up drive it around and see what psi you get at 6psi and 9psi which i recently did... my fuel pressure at idle after driving it for a bit goes down to 53-55psi just takes about 10 mins or so of driving it...
it will do for now i guess...

Michael 99gs
Boost It!
Mods:
no time to put in yet: s-fmu,injectors, and crane ignition.
Hrc Stage 2
Greddy Type S Bov
VC-2
Road Race Catch Can
Greddy Profec B & Switch
Apexi WS Catback
Super Afc
Autometer Boost,
Egt,Tranny Temp Gauge & Cooler
Air/Fuel Light & Digital
Tokico Adjust Struts
Eibach Pro Kit Springs
Front & Rear Upper Bar
CarCraft Interior
Sound System= Bring it On

my fuel pressure at idle
>after driving it for a bit goes down to 53-55psi just takes
>about 10 mins or so of driving it...
>it will do for now i guess...

I dont understand how HRC can claim something works if you have to drive it around for 10 mins for it to work. Its suppose to keep the fuel pressure at what you set it at. There should be no 10 minute warm up period. They are just trying to save money buy saying its suppose to do that. Its complete bullshit on HRC's part to claim you need to let the car warm up. What would you do if you had to wait 10 minutes after you turned your tv on to actually watch cable channels? If it doesnt keep the idle pressure at what its set for, IT DOESNT WORK!!! I dont see the vortech users having problems like this. Face HRC, its JUNK and you owe a LOT of people a FPR that fucking works.

Tell me about it.....I had to pull over 4 times trying to get the fuel pressure right on the way back home from class today. I would set it at 50 psi and it would drop to 40 psi. then I would set it at 50 psi again and it would go to 70psi. Then i set it at 50 again and it went back down to 40 psi. Then i set it at 45psi and I was at home so all i could do was rev the engine up a little and then it stayed at 50psi. I am willing to bet my bank account that when i get up tomorrow and drive to work the fuel pressure will be either at 70 psi again or back down to 40 psi. I just dint know how HRC could use such a poor fpr in their kits. The vortech SFMU is way better. I have no complaints about the pressure at WOT. It works fine under boost but at idle its all over the place. To bad I have no money for a vortech SFMU right now. I am seriously thinking of moving back home to my moms for about 6 months so i can build my car and not worrry about rent and shit for a while. And she only lives about 2 miles away from me now anyway.

FPR problems here too… I love the kit, and I have everything running well now, but the fpr really is a problem. My first fpr would run really rich up to 5k rpms then run lean to redline. I did all of their troubleshooting, and nada. Still didn’t work right. Also, I had to set the damn idle daily. (well I didnt have to but if I wanted it running right i did.)

Well, the shop I was at when we figrued out my fpr was bad only had another cartech, damn them! So we put that in, and the car ran fine.. The car runs well under boost now, but the cartech I got from the shop is the older model I believe.. And the idle fuel pressure wont stay worth a damn, and keeps dropping so low I get a CEL, so i raise the pressure, then the next day my damn idle is at 80..

So now, I'm out 200 bucks, as I have to give the shop the replace fpr hahn sends (if they send one) and I'm stuck with a shitty older one.. And I cant afford the downtime nor the 200 bucks to send this one to cartech..

Anyone have a spare vortech? =)

what i was informed is as follows from hrc tech online:
The idle fuel pressure fluctuation you describe may be attributable to changing vacuum signals on your car. In other words, if the vacuum changes, so does the fuel pressure, and vacuum will vary depending upon engine temperature, accessories energized such as air conditioning, power steering, cooling fans, large stereos, etc. It is possible that when you leave the car sit for a half hour (as described) and then start it back up, that the fuel pressure will be different because the vacuum is different. For this reason, we recommend that the fuel pressure only be adjusted with the engine fully warm, accessories off. Disregard higher or lower pressures that are evident when car has cooled down for any period of time, or when AC or cooling fans are on. Even at warm idle, a variation of plus/minus 3 PSI is not unusual, and will not cause any problems.
if you think about it it does make seens but i dunno the s-fmu people dont have to warm there car up for it to have the correct fp
Michael 99gs
Boost It!
Mods:
no time to put in yet: s-fmu,injectors, and crane ignition.
Hrc Stage 2
Greddy Type S Bov
VC-2
Road Race Catch Can
Greddy Profec B & Switch
Apexi WS Catback
Super Afc
Autometer Boost,
Egt,Tranny Temp Gauge & Cooler
Air/Fuel Light & Digital
Tokico Adjust Struts
Eibach Pro Kit Springs
Front & Rear Upper Bar
CarCraft Interior
Sound System= Bring it On

3psi flucuation is 1 thing. People on here are getting 20-40psi flucuation. Thats unacceptable. Its running they talk about vacuum because before I modified mine, it went from 55 to 80 from just turning off the car to turning it on right away. However, my vacuum stayed the same.

Something is definetly wrong with the cartech FPR's. HRC should use the vortech sfmu's. From what I have heard they hold idle fuel pressure great. I love HRC and their kits are awesome but something needs to be done about the FPR's. I think about 80% of the people with HRC kits get Vortech FPR after they realize that the cartech fpr is crazy at idle. LIke I said above I have been getting 40psi then I get 70 psi. My fuel pressure actually stayed at about 60 psi today all day!!!!! Its a little high but I'll take it.

the fluctuation is a known problem with the cartech fprs. it has to do w/ the material its made of expanding and contracting w/ temperatures. I believe jason opened his up and its uses a shoddy rubber diapharm which also adds to the problem.

supposedly the new billet cartech fpr's fixed that problem.

i got rid of the hahn fpr and now have a SFMU. pressure is constant regardless of engine temp or ambient temp.

with my hahn fpr, it would fluctaute, but always increased pressure, never decreased. once i put the 30lb injectors in, i ran the cartech for a lil while till i could afford the sfmu, and w/ idle pressure down low (around 25psi @ idle) i still got some fluctuation, but only like 5psi, and only seemed to happened when i turned the car off in cooler weather (regardless of how long the car was off tho, ie: getting gas and restart the car and idle pressure would be 5psi higher)

the SFMU is ALWAYS rock solid tho. no fluctation at all, always right on

I got the new billet model FPR installed, and it's WAY better. Not as solid as the SFMU, but it holds idle pressure more or less constant. Between cold starts, the idle pressure can vary ~10psi (due to vacuum? I think more likely due to temp & metal expansion). But the bottom line is- once it's warmed up, it correctly holds the same PSI. (within 3psi) Driveability is noticeably nicer.

Another good thing is that my fuel gauge needle doesn't flutter all over the place... (it used to flutter 20+ psi, I had to guess where the midpoint was to set it). Now it's just a flicker, maybe 2-3psi.
One bad thing is the boosted pressure seems too high. 100psi FP @ 5psi boost. This is with the needle screwed all the way in. I still need to experiment with this, but I'm thinking when I get my bigger injectors, this may be a problem, cause I'll want lower FPs.

If HRC actually refunds me the $200 core I fronted for the replacement, I'm very happy. Can't afford a SFMU right now, cracked piston :(

Dan

Yeah!
I want a new FPR too..
Whats hahns TECH ###
I have e-mailed there tech addy with no reply (some kind of tech suport huh!?)
also what this SFMU..
Sounds like I would want one :)

I have some good news on the my fpr. It has held 52 psi for 2 days straight!!!!!! I check it just about every day now.

I want the new FPR but im not paying them a god damn cent for it. Not even for shipping. I paid them once for shipping, I wont do it again. Its not my problem that the parts they sent suck and dont work. If they refuse to pay shipping I will buy the Vortech when it comes time and the money is there. I just wont pay them anymore money for stuff thats fucked up out of the box.