jimmyg

Ok so maybe u guys can help me diagnose an issue. Car has a cammed ly6/whipple 2.9 @10-11 lbs boost. Ractronix FP 450lph 65 lb injectors , -8 to rail -6 return. Hot wire kit etc.. found out it was advanced a little too much for pump. 24* pulled it back to 18* max. Been messing with VE % to fix afr . Now it goes lean @WOT . Was @ 92% . Went as high as 97% still lean. Fuel pump fuse was melted so I changed holder/fuse still same deal. I'm thinking fuel pump is getting weaker. I ordered another 450 . Could there be something in tune holding afr back? Mast m-90 ecm. Speed density tuned .

Old Geezer

iTrader: (3)

Is this in your Yugo /LS swap, or?
No mention of actual fuel psi. What is it at max boost?
Regulator referenced?
Bad ground to pump?
Lots of things to check before throwing parts at it.
Data logs?

jimmyg

83 cutlass . Fuel pressure set @ 65 lbs
Reg is after rails. Not boost referenced. The grounds look good . Grounded to chassis prob 4 ft from main ground( batt is in trunk) it was working fine till I backed timing down.

jimmyg

Well I tested wideband . Appears to be junk. These new Bosch 4.9 s don't seem to last very long

Lsxford

iTrader: (6)

Move the timing back up a little? I remember a thread a few days ago with timing affecting the afr. There was a wealth of info in that thread but its not on the first page now and im lazy.. Lol

Lsxford

iTrader: (6)

Nevermind. I found that thread and you started that thread too. Lol my bad

So its still going lean. Im trying to remember. You watched a fuel psi gauge while it was going lean and the psi stayed steady correct? Or i may have dreamed that

Isnt 18* still high for 10psi? Most cars i see are running sub 15* at 10psi
​​​​​​

jimmyg

Yes fuel pressure stays steady. Tested WB according to u tube video. This thing is reading messed up . Put it in a gas soaked rag and it was still jumping around.. I talked to mast and they said start at 18* maybe because of meth? I ordered a new sensor. When it comes in I'm going to start reading plugs., and put timing where it needs to be.

truckdoug

iTrader: (25)

so let me clear things up for myself so I can follow along

what is your fuel?

what % methanol are you spraying, how much and when does it come on?

LLLosingit

iTrader: (4)

Without a boost referenced regulator when you're at 10lbs of boost your pressure gauge may read the same but the engine is seeing less fuel because the injector is seeing 10lbs of head pressure. So if your base pressure is for example 55lbs with no boost then at 10lbs of boost your injector will only flow what it's rated for at 45lbs of pressure.

jimmyg

93 e10
Probably 70/30 meth/water . 625ml nozzle . It's progressive. Comes on @4 lbs all in @10

jimmyg

Honestly, I just set it up the way mast told me too. It was originally N/a w/ a mast vvt cam. When I put the whipple on, I set it up how they wanted since they sent me the base tune. It's always worked fine until I started to mess with it. It was too advanced for pump so the knock sensors were prob pulling timing. So I turned it down. Then this lean condition @wot started.
Im pretty sure the wideband is smoked. I ordered a new one so we will see. I totally get what your saying about the injectors . How would you set it up? I think mast wanted 65lbs of fuel pressure because the fast 65lb are rated @58psi.

jimmyg

The fuel system is as follows. Racetronix hanger w/Walbro 450, -8 to engine bay ,y fitting then -6 to each side of rails. -6 to reg, -6 return I have an aeromotive boost ref reg but no vacuum line hooked up
I could hook it up pretty easy, but what to set fuel presssure to? Could I leave it at 65 and hook up line?

LLLosingit

iTrader: (4)

I run a Holley EFI system on a 6.0 LY6 and LSA supercharger(10lbs boost). I have a boost referenced regulator and run a base pressure of 55lbs. Without the boost referenced regulator the Holley system would still calculate the fuel based on the set fuel pressure, Any drop in pressure would cause a lean condition. So 10lbs of manifold pressure means the injectors need an extra 10lbs of line pressure to overcome it.

Edit: you're speed density tuned so the computer doesn't calculate fuel based on a maf so I would think you would also need a referenced regulator.

jimmyg

So I'll hook the line up. It' should raise FP 1lb per lb of boost. Do you have a build thread? I wouldn't mind checking it out.

LLLosingit

iTrader: (4)

I don't have one yet, It's a 2000 S10 Xtreme with a 13,000 mile LY6 and TR6060 6-speed and new LSA supercharger. Truck is done but now I'm working on my Son inlaws 73 Nova 6.0 swap.

LLLosingit

iTrader: (4)

14" brake upgrade, Stock rotor in the top portion of the picture.

jimmyg

Nice! It must go pretty good

brandon6.0

iTrader: (32)

am I reading this right u say u are around 97% at wot in your VE table? if so yes I woud think u are lean. Stock NA ve tables have fueling around that area. What I would do is go back to a stock VE table. Thin add 15% to everything in the boost region. give it a try and see what happins. If still lean hit it with another 5% and so forth. if fueling doesn't try and go rich u have a fuel supply problem. u need a fuel pressure gauge on it asap.

jimmyg

Ok I will give it a shot. I have a fuel pressure gauge (AEM) it reads 65 lbs all the time.

jimmyg

It was working fine until recently. Been beating on it since last summer. This all started when I got the meth kit and started messing with timing and afr. There is a boost page in tuning software. I suspect it adds fuel to VE