19psi to much?

[91TSI505]

Was on my way home tonight and a lexus IS 300 came up on the side of me and wanted to dance a little so i gladly accepted the offer and showed the $30,000 car a step or two,now this was on the freeway(just rained,cool temp night).I have my MBC set to 15psi i usually top out right there but tonight i hit 19psi in 4th,it was a cold night also,could this be why?...is this OK?I have no fuel mods YET,just exhaust,intake,MBC,wires.While im on the subject,should i get the 255 Wahlbro,or the 190(Gettin a FP in a week),i am going to eventually get a PTE 50 trim,but will the 255 act funny w/ my 14b and no AFPR,is rewiring a wahlbro a must or is that for stock Fuel pumps?Thanks for all of the help

 

[Omega]

I will answer the fuel aspect.

The 190 is good for 450HP. If you really want to buy the 255, you MUST buy the FPR. Don't bother installing the FP without buying the FPR, you will be wasting your time.

The rewire depends on the car really. Some have inherantly bad (or old) wiring so they need the help. When you replace the pump, do the rewire since you will be halfway there. When you do, don't buy a radioshack 50 cent special relay though. Buy a good Bosch one and get the harness to sder the wires to.

 

[91TSI505]

Thanks for your help with the fuel subject Omega

 

[2GStreeT]

Do you need an FPR with a 255LPH High/Low pressure?

 

[90AWDTalon]

I've got the 255 low pressure, I'm using the stock FPR and have no problems. From what I understand you only need a FPR with the high pressure pump.

 

[candela]

The 190 is good for 450HP. If you really want to buy the 255, you MUST buy the FPR. Don't bother installing the FP without buying the FPR, you will be wasting your time.

Im going to settle this once and for all. The stock ecu is very good at what it does, and when modifying our cars (not to heavily) the stock ecu is ALWAYS helping us as there are little ways to get around the shitty things about it. When you install a pump that puts out ~double the flow (~43psi) you WILL overrun your stock FPR. Is that a bad thing...depends on the car, person and tuning stature.

If and when you feel like installing a 255lph pump and do not install a FPR that can bring the base pressure at idle back down to normal (as it will most definetly increase it) you may or may not have issues. The ecu will respond to everything you do to the car in one way or another and the fuel trims will eventually be adjusted to compensate as much as possible. After this happens you may never even want to get one because your dsm runs just like stock without a FPR although you have a 255 in the tank While there are a few other guys, one saying that he read this on the net and when you get this you must get this, another saying that he has experience in the subject and when he installed his walbro his car, it ran crappy and puttered and hesitated sometimes and it happened only after he installed the FP... Well I say that the 190 is good for a lot more than people give it, but if you want over 400whp then I woudl consisder getting the 255. I had a aeromotive unit with my FP and it DID infact smooth things out, made it easier to tune and idled a tiny bit better, but without the regulator and the 255HP I wasn't dissapointed, nor did the car run shitty by any means as the ecu was taking care of what needed to be...

91TSI505- If you are going to be with a 50trim and want its full potential later down the road then you should probably get a 255lph. Rewired or not doesnt really matter as the stock wiring (as long as its not crappy old and rotting) will be more than sufficient enough for any power level a 50trim will put out IMO. Get hte FP, drive it for a week and if you can't stand it then get a FPR and adjust as necessary, if its fine (which it prolly will be) then don't bother until you get to the point where your ready to start really tuning and you get on the dyno.


Austin

 

[91TSI505]

OK..........that pretty much summed it up for me.i'm going to get the 255hp and if need be i will get a AFPR,Thanks Austin!!

 

[2GStreeT]

So what sort of adjustments would you make on the FPR to run a 255LPH. Would you raise or loswer the pressure

 

[JayHass]

Originally posted by 2GStreeT
So what sort of adjustments would you make on the FPR to run a 255LPH. Would you raise or loswer the pressure

Neither. The stock FPR can't flow enough so the 255lph overruns the stock FPR an pressure goes up. With an aftermarket it can flow enough back to the tank and you don't have this problem.

candela: I was getting ready to write a response similar to yours and hit yours. I agree 100%.

For reference sake I also have a 255 with the stock FPR in planning for a nice big turbo and it runs fine. Not perfect but more than acceptable IMO.

Edit: With the mods you listed and cool weather I wouldn't sweat a short burst at 19psi. If you feel the car hesistate or "mini" buck get out of it because 99% that's detonation.

 

[TuRBo'DTWiX]

my friend has a 92 laser with the following mods K&N, free mods, 2.5 downpipe, 3" catback no cat, boost gauge, mbc, 255 fuel pump, and a 16g turbo


Is it safe to run 20psi ?? if i run it lower like 15 or 16 psi will it affect my car like fuel overflow or sumthing

 

[Nomad666]

The RRE website can answer this question.(the middle of the page)
http://www.roadraceengineering.com/eclfuel.htm