afpr - what do I need?

[Passnu2]

Will I need to upgrade to a AFPR?

16g small MHI Turbo
550cc injectors
255 lhp
manual boost controller (looks generic - came with car)
Evo III Maf
SMIC w/ Hard Pipes
Forge BOV

OEM fuel rail/fpr

also if I need an AFPR do I need a rising rate? I see there are several options.

car is almost back together and I do have a manual boost gauge and A/F gauge that will both be installed to monitor everything.

Looking for a clean safe balance with everything I have. I picked up the injectors, fuel pump, and MAF.

 

[gophishy10]

For what you have, I would have gone with either the evo fuel pump or the walbro 190. Either one rewired would be more than sufficient for your setup. I have always heard that if you go with the walbro 255, you need an afpr because it will overrun the stock fuel regulator.

 

[Bud92gsx]

Fuel rail fitting, afpr,your an line from rail to fpr.Thats it.

You needed the afpr before you installed the 255,but what do I know.

 

[Passnu2]

Cars not together to drive,

So if it has a 190 lph in the tank I should stick with this and save the 255 for down the road?

 

[Bud92gsx]

The 190 will be fine for your 550s and pump gas with no afpr.But down the road you will outgrow the 550s,and time for the afpr,and 255.

Upon second thought though.With no tuning solution, you wont even need the 550s or fuel pump, cause you cannot utilize them correctly.

 

[Wil_Own]

Do it once do it right wally 255,rewire kit,afpr one less thing to buy and worry about down the road.

 

[Passnu2]

I thought I had to tune the car because of the Evo Maf? it was my intention after I have it all back together.

Do it once do it right wally 255,rewire kit,afpr one less thing to buy and worry about down the road.

This was my thought when I got it. So what does our car require? I see rising rate ones, 1:1 ones, ect...

 

[ASPTech1]

The tuning may have been implied.

I have somewhat of a similar set up with my 2g.

PTE 5557e Turbo
550cc injectors
255 lhp
2 stage manual boost controller
3.5" GM MAF with MAFT 2.02
SMIC w/ Hard Pipes
1st gen diverter valve

I've been trying to experiment and get around not having an afpr. I was only able to lean out the air/fuel to 10.3 on the wide band while running 21 psi of boost at WOT. After many hours of trying different things, I have finally given up and decided to start searching for an afpr as I should have in the first place.

I believe that a 1:1 rise with boost will be the easiest to work with, and you will have to make sure you get one that will allow you to turn down the fuel pressure if needed since you have a high pressure fuel pump. FMU's with different ratios tend to work well with supercharger applications with refined tuning. I'm a little familiar with those because I was supercharging vipers and twin turbo'ing lambo's at my last job

I'm really liking extreme psi's fuel lab "515" complete afpr with gauge kit. I've looked at some used ones, but I would look into rebuilding the internals if you decide to go that route just to be safe. I hope this info helps.

 

[WES_393]

The factory Fuel Pressure Regulator is a 1:1 rising rate regulator- For every 1psi of boost pressure, the fuel pressure raises 1psi. This is important in order for the injectors to maintain a constant effective pressure. If you have 43psi in the fuel rail, and 20psi in the intake manifold, then your fuel injectors really only have 23psi behind them and therefore flow much less. Since the ECU is programmed for a specific flow rate, this would obviously cause a problem.

The main reasons for installing an Adjustable Fuel Pressure Regulator are:
- Precise base pressure setting
- Consistent 1:1 regulation
- Preventing regulator "over-run"

In my opinion, a quality AFPR is a necessity for anything above the stock fuel pump.

 

[97gst5887]

I have been using the fuel lab fpr kit from extreme for 4 years now. The only problem I've had was the gauge quit on me, but that was a cheap fix.

 

[Passnu2]

Thanks for the replies! I pick up the head later this week and hope to get it all together on the next few weeks. Ill just go with the afpr to do it right, plus I haven't opened the tank so who knows the condition of the oem pump or if its original.

 

[LandSpeed-DSM]

If you are doing the re-wire, regulator install, etc.

Splurge on replacing the stock filter and banjo bolt line that goes to the rail. Or at the very least, delete the stock line between filter and rail. I can't remember the figure exactly but, it brought IDCs down considerably which means it was a significant restriction to flow.