walbro, FPR needed?

[4g63t]

I have a wallbro 255 lph fuel pump do I need a ajustibul fuel pressure regulator to run it? If so ware can I find one that has a gauge on it for cheeper? (under 100$) what would i run like without it

 

[oldman]

I dont know the brand because I baught it from a local dsmer.

What does the pump say? How about calling the seller and ask? You're acting as this is not crucial information.

it said to ajust to 43.5 to make it posibel to max out your injectors.

Who and what is "it"?

So I need to ajust it back to factory pressure 37psi?

Correct, unless the eprom was changed to 43.5 psi like mine but I doubt it.

 

[napkinthief]

Im confused, if the NT FPR is good for the turbo cars, why does it have to be changed to a 12:1 when I go turbo?

 

[4g63t]

"it" is jeff on the forum on the dsmchips website http://www.otsmotorsport.com/dsmchips/viewtopic.php?t=286I dont think my pressure got changed on the eprom chip the pump is a walbro 255 but if you ment afpr I have been looking at pics on the intornet and it is looking more like the b&m witch sux, because it is the wrong one.. right?

 

[oldman]

Im confused, if the NT FPR is good for the turbo cars, why does it have to be changed to a 12:1 when I go turbo?

I'm sure what's going on with the 420a but I was talking about the 1G NT 2.0 fpr.

 

[oldman]

I have been looking at pics on the intornet and it is looking more like the b&m witch sux, because it is the wrong one.. right?

Correct, it will do nothing to solve your fpr overrun, the main reason for the afpr. How much did you pay for it? New?

 

[4g63t]

I paid 30 for it and it is used. I am still going to use it for now dispite the bad gas milege and install the gauge after school to check the base pressure. Onley untill I get the aeromotive one. Will I be safe for now?

 

[oldman]

I paid 30 for it and it is used. I am still going to use it for now dispite the bad gas milege and install the gauge after school to check the base pressure. Onley untill I get the aeromotive one. Will I be safe for now?

It will run safely as long as the overrun isn't too bad, the gauge will tell you how bad.

 

[4g63t]

It will run safely as long as the overrun isn't too bad, the gauge will tell you how bad.

Ok ill find out tonight and get back as soon as I can.

 

[4g63t]

ok it is at 39 40 psi.... I can only turn the pressure up with my regulator.

 

[oldman]

ok it is at 39 40 psi.... I can only turn the pressure up with my regulator.

How much vacuum are you pulling at idle on your boost gauge? You do have a boost gauge right?

 

[4g63t]

yeah i havent paid much attention to the vacuum so i will look closer later, and get back to you.

 

[oldman]

yeah i havent paid much attention to the vacuum so i will look closer later, and get back to you.

I do need the vacuum reading to tell you how bad you're overrunning the B&M.

 

[4g63t]

It is at 15

 

[oldman]

-15 inHG means at least two things.

1. Boost/vacuum leaks as you're suppose to pull about -20inHG with stock cams.

2. -15inHG = about -7.5 psi, 37psi (1G base pressure) - 7.5psi vacuum = 29.5 psi

You're overrunning the fpr by 10 psi, which will get worse after you preperly fix your boost/vacuum leaks.

 

[girlieracr4g63]

ATTN: OLDMAN(wiseman)

I hate to jump on someone elses thread and ask a question. This thread really has alot of great info. I really need to ask this though. What should vaccum be with FP2s? My current fp is 42psi with vaccum off and 40psi with vaccum on. Current vaccum on boost guage is -9Hg. Idle is very spurratic! I had a full throttle afpr and it died on me so now I had to borrow this B&M fpr. I do have a 255fp. Question is this how much do you think Im overrunning? I know that I need to get another afpr, have you heard of cutting one spring on the B&M so you can lower the pressure? Should I go with 37psi or less?

I was also wondering if the full throttle afpr could be rebuilt? Not sure what happened to it but I only had it for many 200 miles.

Thanks for you time and the space,

Wendy

 

[oldman]

I really need to ask this though. What should vaccum be with FP2s? Current vaccum on boost guage is -9Hg. My current fp is 42psi with vaccum off and 40psi with vaccum on. Should I go with 37psi or less?

Wendy, fp2's should be about the same as 272's which is around -12inHG, have you leak tested lately?

Question is this how much do you think Im overrunning?

Possible vacuum leaks aside, -9inHG = -4.5 psi. 37psi (base pressure) -4.5psi = 32.5 psi, you're overruning the B&M by 7.5psi. Not too bad but partly due to cams and possible vacuum leaks. Expect overrun to get worse if in fact leaks were found and fixed.

I had a full throttle afpr and it died on me so now I had to borrow this B&M fpr.

Would have been the same as putting back the stocker.

I know that I need to get another afpr, have you heard of cutting one spring on the B&M so you can lower the pressure?

No way. The reason the stocker gets overruned is because the return orifice is too small to bleed off exccess volume produced by a larger pump in order to maintain 1:1 raising rate with the intake pressure. The B&M Command Flo unfortunitely doesn't replace the stock FPR, instead it modifieds it while keeping the return orifice of the stocker, this is why the Command Flo does not work for DSMs. Maybe an all out track car but definitely not a street DSM.

I was also wondering if the full throttle afpr could be rebuilt? Not sure what happened to it but I only had it for many 200 miles.

Warranty?

Idle is very spurratic!

Every typical of more agressive cams but I would still hunt for vacuum leaks and replace the afpr, it will definitely help. Good luck.

 

[4g63t]

ill check over all my vacuum sorses and then get a better afpr, Is 10psi going to be deadly to my engine?

 

[oldman]

ill check over all my vacuum sorses and then get a better afpr, Is 10psi going to be deadly to my engine?

Visual inspections will get you no where, a boost leak test is what is needed. 10psi overrun will not kill your car but will greatly affect your fuel economy and drivability at idle and part throttle, degree varies from car to car.

 

[4g63t]

Vary imformational thank you, I will be doing a boost leek test first as soon as I get some free time.

 

[4g63t]

ok I made a tester and it worked grate I found two leaks #1 the vacuum hose that connects to the wastegate from my mbc wasn't sealed. #2 The recurculation from the valve cover to intake manifold had a huge tear in the back side of it. Ill finish fixing these then do it again to see if that was all the leeks. I fixed the wastegate leek and the gauge staid the same so im hoping the other will make a difference. .

 

[TrboANTsi]

i hate to jump in this also with my question.but can someone just recommend a fpr and whats needed to go along with it...because i just ordered a 255.. and theres so many to choose from in the parts cat.

 

[eclipsh]

http://www.importevolution.com/product_info.php?cPath=24_45&products_id=1620 Import Evolotion offers the best deal I've found for a good FPR unless you count buying used. The install kit can be half the price of a FPR.

If you do buy an individual FPR and need line/fittings AN Plumbing had the best prices I found.

http://www.anplumbing.com/shop/index.php

 

[eclipsh]

So I got my AEM FPR, courtesy of Oldman, installed and set at 37.5psi.

My idle is actually better, I didn't know I had a real problem with it.

My fuel trims at top and mid are now holding steady at 100.

My Lower fuel trim is at 118 and the car no longer likes to start right away. I suspect a pressure leak of some sort but I can't find a source. I think it might be some debris that got into the lines from the FPR install causing some problems.

 

[4g63t]

Thats different my low trim jumped to 139 due to my deadtime on my injectors, but I have maft now and it fixed it.

 

[eclipsh]

Actually, I went to my mechanic's shop this afternoon and we isolated the FPR as being the problem. It isn't holding back pressure when the car is shut off.

So it is either crud in the FPR or it's worn out.