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[Eville140]

Okay.  Here is the setup

E-85 fuel
Fuel cell with a -8 feeding a Walbro 255hp inline.
-6 from pump to rail, -6 from rail to aeromotive regulator.
-6 return line.
Injectors are the Delphi/Rochester 95# injectors

Base fuel pressure is @ 50#
and boost is currently at 30#

Car pulls like a mofo till about 6500 rpms then goes lean hard.  Keep adding fuel to the map and it doesn't seem to help. 
Checked the regulator with a compressor and it is raising like it should.  But when out "tuning" it looks as if the pressure is not raising as high as it should.  Hard to tell since its a damn handful.  Going to rig up an easier to see fuel pressure gauge later today and make some more runs.

Another question as to pulse width,   Say at 7500 rpm..what pulse width time would have the injector open all the time?

Thanks

[runsfromdacops]

if the fpr wont raise like it should i would say its the pump..

[Joseph Davis]

You'll run out of injectors first, if the pump is wired correctly.  What gauge wire, and where are you grabbing power and ground from?

[Eville140]

Got a big weldng wire going from the alt. straight back to the fel pump relay (replaced the relay today for giggles...no change).
Ground is the battery terminal
datalog show a pretty steady 13.5-14v

[lilpooh21186]

 How lean does it go look into caluclating your duty cycle.

[Eville140]

Really suck video of ghetto test setup
http://www.eville140.com/video/fuelpressure.wmv
(I slowed the video to half speed, car is faster than that  )

Boost is on the left
Fuel Pressure on the right

At start of video motor in vac and FP is around 40
Once the go pedal is down vac goes to 0 and FP goes to 50  
Fuel pressure goes up with boost to about 70 than drops down to 60
The black mark on the FP gauge is 80psi (which it should hit)  The next mark down is 60 (where the needle settles)

Guess I will order another pump.
Swap it out and see if it still does it.  If so put in both pumps.
If the one new pump fixes it, toss the old one in the trash.

Joy, now my fuel map in boost is all fucked.

[Joseph Davis]

Got a big weldng wire going from the alt. straight back to the fel pump relay (replaced the relay today for giggles...no change).
Ground is the battery terminal
datalog show a pretty steady 13.5-14v

Datalog shows voltage across a no load ECU, not the fuel pump.

You have an old car, that's had it's chassis re-insulated with a sweet coat of fresh paint.  Ground the fuel pump to the block.

It could be the pump's getting old.  All my experiences are with 255HP, I've been to 636 whp (gasoline) with one on stock CRX fuel lines.

[bigdaddyvtec]

Ross' car made 637. I have Both the 044 and the HP with their own dedicated power and grounds going straight to the battery with dedicated relays doing the dirty work individually for each pump. Well see what it gets with Sewells pimpjectors soon enough.

[sewell94]

Unless your engines a non power making POS, at 30lbs you'll be out of pump AND injector.

 I've never made more than ~465HP on a walbro on e85. I've had 1000's(on 50psi) max out on e85 at ~490hp. Your pump/injector combo is good for 450-475hp safely.

[Eville140]

Unless your engines a non power making POS, at 30lbs you'll be out of pump AND injector.

 I've never made more than ~465HP on a walbro on e85. I've had 1000's(on 50psi) max out on e85 at ~490hp. Your pump/injector combo is good for 450-475hp safely.

Well, compared to a honda it probably is.  The 3tc head has peak numbers probably in line with a stock D16 and low lift numbers that would get laughed at. 
Just an example to get the idea


But the motor can take a beating.
If I had to guess I would say I am in the 400-425 rwhp range.  And probably rich at that so I might be at the limits, either that or I have pump problems.

Now where to get a walbro from without the fear of getting a fake?

[sewell94]

From the symptoms your having i'd change the fuel filter first.

[Eville140]

From the symptoms your having i'd change the fuel filter first.

I did that, even ran it without the element with no change.

[Joseph Davis]

From the symptoms your having i'd change the fuel filter first.

IIRC, it's never seen gas.

If I had to guess I would say I am in the 400-425 rwhp range. 

Given the atrocious bsfc of the 3TC, and your failure to report back on duty cycle, I think the system's just maxed out.

[sewell94]

Unless your engines a non power making POS, at 30lbs you'll be out of pump AND injector.

If I had to guess I would say I am in the 400-425 rwhp range. 

Given the atrocious bsfc of the 3TC, and your failure to report back on duty cycle, I think the system's just maxed out.

x10

[Joseph Davis]

If I had to guess I would say I am in the 400-425 rwhp range. 

Given the atrocious bsfc of the 3TC, and your failure to report back on duty cycle, I think the system's just maxed out.

x10

I feel proud to know the man.

Randy, send me your address and I'll ship you the one and only Stephen T. Smith McCaffey College ID card as a tribute to your accomplishment.

[Eville140]

 

Okay, going to try and answer the duty cycle question.  Will pulse width do?  MS lists a duty cycle also.

At 7000rpm and 30# of boost PW is at 32.7ish with a Air fuel of 11.7
It has a number of 187ish (what ever the hell that number means I have no idea) next to DutyCycle
But this is with the fuel pressure being close to 20# less than should be.

At 6000rpm and 20# of boost PW is at 13.ish with air fuel again at 11.7
At 20# the fuel pressure is much closer to the correct 1:1 rise with boost.

[Joseph Davis]

17ms injector pulse at 7000 rpms is 100% duty, meaning the injector is on 100% of the time.

Here's a cool calc, play around with it and get a feel for it.  http://www.stealth316.com/2-calc-idc.htm

[Eville140]

Have another 255 in route,  will post up results of what I fgure out.
To hot to go racing this weekend anyways.

[sewell94]

17ms injector pulse at 7000 rpms is 100% duty, meaning the injector is on 100% of the time.

Here's a cool calc, play around with it and get a feel for it.  http://www.stealth316.com/2-calc-idc.htm

Thats a for a sequential system,   Most MS I've used are/were batch/bank to bank which would double the duty cycle on that link.

[HiProfile]

You need to quadruple fuel pressure to double flow. So don't worry much about pressure. You'd loose "injector" but not enough to make another 500-1000rpm's of power. Another thing about fuel pressure, turning it up doesn't always give more fuel. This is usually near the pump's limit.

I dealt with an issue like this before. I was doing work on my friend's boosted fiero, and it had an ancient Haltech in it. DOS based, and very screwy. Each RPM "row" was it's own page, with the various load columns. We could not enrich it after 5500rpm, turns out my SSI-4 was reading rpms correct, but the software was >500rpm off. My advice is to try the rpm row below what you're cranking fuel on and see what it does. If you can't get those to enrich, it's not rpm-based issues.

Also if you turn down the boost slightly, you'd probably notice you'll get mroe rpm's before it goes lean - assuming your boost level is still efficient for that turbo.

[Eville140]

Well F me with rusty log manifold. 
I think I found the problem. Started pulling crap out to get ready for the two pump install and under the backseat it looks like over the winter some mice took up residence.  Well for some reason it looks like the little bastrards chewed on the power wire. It is down to about 4 strands in a spot. 
I must have had something greasy and tasty on m hands when I put it in I guess. 
But second pump is here,  aeroquip fittings are here so might as well stck them both in.
The one walbro I'm running now is probably as old as some ofthis boards members anyways. I'm
sure it won't mind the help.

[Eville140]

Got both pump installed, new wire everywhere. Fuel pressure is perfect now.
Have lots of work todo on the fuel map though. Was rich off the scale past 15# of boost.  But have gotten it much closer on just a few runs.  Amazing how much easier tuning is when the car runs te same tme after time.
Even ran it on each pump indvidually and all seemed fine.

Atleast I don't have a bunch of money in my worthless upgade. Kept. Rhmt as much as possible
  

[TTC]

ON a side note, would it be safe to say that if i use 10 or 8 guage wire for my amplifie ( from battery)r in my trunk I can use that wire to power my fuel pump as well? THen ground at the body or block?

Thing is, the wiring on my fuel pump isnt anywhere near that size on the walbro if memory serves correct, im just not sure when the old shitty 20 year old wiring is still good or up to the task of 300.  Especially to ensure its got reliable amperage.

[Eville140]

ON a side note, would it be safe to say that if i use 10 or 8 guage wire for my amplifie ( from battery)r in my trunk I can use that wire to power my fuel pump as well? THen ground at the body or block?

Thing is, the wiring on my fuel pump isnt anywhere near that size on the walbro if memory serves correct, im just not sure when the old shitty 20 year old wiring is still good or up to the task of 300.  Especially to ensure its got reliable amperage.

The wire in the picture is 10 gauge and what is recommended to be used. 

My battery is in the back about 12" from the pump so I went to the battery for ground,  I have a fat wire coming from my alt. to the exterior kill switch so I got the power from right there.
Also went ahead and added another big ground strap from the motor to the frame.

Now if it would just drop below 100 degrees on a test and tune day, fucker rips at 34# of boost  If the DOT's will hook up it should hang the wheels pretty good.  :yes:

[2slow]

Off topic but did you ever get those tags made up for your manifolds like weir has?