My STI is alive again, here's what happened - Page 3

Shawn96VR-4 · #31 (**permalink**) 10-29-2007, 08:29 AM

Quote:

Originally Posted by jays05

I'm ready for ya.

I maxed out the fuel system last night

and I wasn't in reverse.

WOW. Details?

bennyfizzle · #32 (**permalink**) 10-29-2007, 09:37 PM

moar

jays05 · #33 (**permalink**) 10-30-2007, 08:19 AM

There isn't much else to say. The injectors are maxed at 28psi and 7500rpm (and zero knock counts at that level). Sure I could probably run more boost in the midrange, but the MAP sensor is having none of that. I turned boost back down to 25-26psi. Still feels like I am going to break something in the drivetrain.

I swapped the plugs back, so it has NGK Coppers in every hole. Also changed the oil to Rotella-T 5w40 synthetic. Gonna upgrade the rear axles next...

Oh yeah, and my video camera is broke, so no videos for the time being.

Shawn96VR-4 · #34 (**permalink**) 10-30-2007, 02:37 PM

Is it just the map sensor? You haven't maxed out the fuel setup until you start leaning out. Can you fudge it like my piggyback and just do max corrections to throw as much HZ at it as possible?

jays05 · #35 (**permalink**) 10-30-2007, 04:46 PM

Quote:

Originally Posted by Shawn96VR-4

Is it just the map sensor? You haven't maxed out the fuel setup until you start leaning out. Can you fudge it like my piggyback and just do max corrections to throw as much HZ at it as possible?

The injectors are at 95%. I think the underlying problem with fuel is the single walbro fuel pump.

I need a stiffer spring in the wastegate too. Boost control above ~26psi is kinda scary/imprecise. Wastegate boost around 20psi would be perfect.

This is as far as I planned on pushing the motor this year. I expected to run out of fuel around 25psi like others have when using the same parts, but the meth injection gives some extra headroom.

Shawn96VR-4 · #36 (**permalink**) 10-30-2007, 04:50 PM

Sounds like you need 19V to that FP.

1320ride · #37 (**permalink**) 10-31-2007, 03:16 AM

buschur racing makes a dual in-tank walbro setup shawn that isnt very expensive and will support over 1k whp.. if i remember correctly, isnt that the way u were goin jay?

jays05 · #38 (**permalink**) 10-31-2007, 06:53 AM

Yeah I already talked with them about the dual walbro setup, and I already have the second walbro sitting here. I'm just in no rush to upgrade the fuel system. 25-26psi is plenty and I need to work on the driveline before I break something. DSS rear axles are next... then an EL header, and maybe the fuel system after that.

sully93vr4 · #39 (**permalink**) 10-31-2007, 06:54 AM

I have twin Walbro's and love them. I shouldn't ever have to worry about starving for fuel! It was easy to fab them up into the bulkhead as well, and at ~$80 a pop its a no brainer, good fittings and fuel lines are a $$ though.
The pumps even tell me when I'm getting low on fuel!! it just sounds like a little jet in the trunk, lol.

Shawn96VR-4 · #40 (**permalink**) 10-31-2007, 09:59 AM

Quote:

Originally Posted by 1320ride

buschur racing makes a dual in-tank walbro setup shawn that isnt very expensive and will support over 1k whp.. if i remember correctly, isnt that the way u were goin jay?

Yea, I am aware there are dual setups (STi has like every mod under the sun available) but I am not a fan of multiple FPs.

bennyfizzle · #41 (**permalink**) 10-31-2007, 12:03 PM

sumppppppppppppp and a big burly helicopter sounding aeromotive or something lulz

BoxerSix · #42 (**permalink**) 10-31-2007, 12:46 PM

Quote:

Originally Posted by bennyfizzle

sumppppppppppppp and a big burly helicopter sounding aeromotive or something lulz

Bingo.....one big Aeromotive inline. #002-11104 or if you think 900hp isn't enough then #002-11102 is good for about 1200hp....

I'm not a fan of twin pump setups myself either. I've personally seen (and rebuilt) the aftermath of twin pumps setups failing where one pump mystically dies and the FP drops off because the second pump is not enough to keep up with fuel demand, yet enough that the motor doesn't stop running so you run crazy boost on little fuel. At least with one pump if it dies, the motor stops running alltogether

If you can't get enough fuel in a street car from a single pump.....you DO have too much power for your own good

jays05 · #43 (**permalink**) 10-31-2007, 12:53 PM

Yeah, but on the other hand, running twin pumps seems more sensible than jacking up the voltage to a fuel pump that sits inside the gas tank... something about that just doesn't sit right with me.

The aeromotive fuel pump - still looking into it. I found some info on running it off the OEM fuel pump controller, so you don't have 100% duty cycle all the time. Sounds like a step in the right direction.

BoxerSix · #44 (**permalink**) 10-31-2007, 12:58 PM

Quote:

Originally Posted by jays05

Yeah, but on the other hand, running twin pumps seems more sensible than jacking up the voltage to a fuel pump that sits inside the gas tank... something about that just doesn't sit right with me.

The aeromotive fuel pump - still looking into it. I found some info on running it off the OEM fuel pump controller, so you don't have 100% duty cycle all the time. Sounds like a step in the right direction.

I agree with you on one account there

FP drivers suck and are just one more thing to fail in the system.