Alright guys, as most of you know i've had the evo16g on my car for a bit now.

ANyways, i'm having problems getting it fine tuned. I can't see decent timing plast 12 degrees from 4-6k, then it jumps back up to 17-20 advance at WOT. I'm also running pretty rich, and drivability sucks--partial throttle leads to serious bog at higher rpms.

I'll post a log in a bit, but my fuel mods are:

660's
rewired walbro 255 lph (non hp)
SAFC-II
(greedy FMIC)
black mark mod on my rear bumper above the exhaust x(

I'm looking at getting an AFPR, re-rewiring my fuel pump, and trying again now that its colder outside. ANy thoughts on fuel pressure regulators? I really still don't understand why they're useful in tuning, but I know alot of guys use them here. The one i'm looking at is a used aeromotive one off a Tsi AWD.

Can anyone shed some light on why we actually use FPRs for me?

thanks!
matt

www.fullthrottlespeed.com they have the AFPR I bought, works very well, they build it there actually, may take a little while to get it from them, they were swamped when I ordered mine. Reason for needing it, your aftermarket fuel pump outflows your stock FPR which takes your fuel pressure from like 42/43 where it should be to around 50, at least that is where mine was with my 255lph pump. With the AFPR you can bring it back downt o 42/43 where your computer thinks it is, and it will also lean out the fuel.

Correct me if I'm wrong on this anywere guys.

To go with this, you can get a B&M fuel pressure gauge from www.roadraceengineering.com or www.summitracing.com or anywhere really and it will bolt directly onto this AFPR.

thanks! I thought AFPR's only raised fuel pressure though... ??


This would probably explain my drivability issues at higher RPMS....

No, you can raise or lower the stock fuel pressure with the AFPR above.

This could also explain really shitty fuel mileage, if you have noticed lower mileage than usual.

I have the Aeromotive AFPR and it works beautifully. All the AFPR does is allow you to adjust base fuel pressure by controlling the blockage after the fuel rail. Then, to allow cars with forced inductiuon to meet the massive fuel requirements of high boost, the AFPR also give a 1:1 increase in fuel pressure per PSI. For every pound of boost you run, the AFPR increases FP by 1 psi as well.

If you set your FP at 43 psi (suggested setting), and are cruising along at 4 psi, you'll have 47 psi of pressure. Pretty good stuff.

As far as monitoring it, I have an electric FP gauge in my car that uses the stock sender fitting (well it would have but I did a custom fuel line and got the FP sender adapter piece for it that made it super simple to adapt.) I also have a mechanical gauge on the AFPR on the engine bay, but at this point it is basically useless since I can monitor the FP from the driver's seat.

Honestly, I would recommend the Aeromotive over anything else, but that is from my personal experience and limited research I had done on the subject.

Also to not: Some AFPRs give more than a 1:1 increase in FP per PSI of boost. When running HUGE boost amounts and power, some people need a 3:1 or more increase to make sure the car doesn't run lean. These setups aren't commong in streetable applications

Is it just the Aeromotive FPR that does the 1:1 increase for boost, or is that any AFPR?

Originally posted by FlyinEsi
Is it just the Aeromotive FPR that does the 1:1 increase for boost, or is that any AFPR?

Most are 1:1 as far as I know. The ones that are greater tend to be super expensive and pretty massive pieces of machined goodness.

Usually that is plastered all over the product if it is 3:1 or greater.

Thanks matt I appreciate the info---

Have you found it worthwhile to be able to monitor your fuel pressure while driving? As in, on a scale of 1-10, how useful would you rate it (if you have the mechanical adapter, which probably isn't that useful considering you can't build boost at idle)? Better than something like an oil pressure guage?

thanks again!

matt

Originally posted by Vandy420a
Thanks matt I appreciate the info--- Have you found it worthwhile to be able to monitor your fuel pressure while driving? As in, on a scale of 1-10, how useful would you rate it (if you have the mechanical adapter, which probably isn't that useful considering you can't build boost at idle)? Better than something like an oil pressure guage? thanks again! matt

Since I blew my engine, I find every bit of info in my face in the car to be invaluable. I have Boost, EGT, Knock, Oil Pressure, Coolant Temp and Fuel pressure in car and will most likely get oil temp, and some others at some point.

I just learned my lesson and after psending so much on the car, I want to know exactly what is going on at all times in it now. I now err on the side of caution as a rule of thumb.