FUEL VOLUME issue!!

SYCLONE#1531

'MOFOFAST
KINDA long.....
Just testing my truck out today and I was greeted with a stalled bucking back in forth. truck coasting back in my driveway..Right before this, I noticed today under boost my afrs were jumping around in the 14.5 / 15 range. not a good thing with the boost levels I run (25psi)... Ive got a walboro that I installed a few years ago from RPM. I also have 8an lines coming from transfer case to rpm rails. Just installed. Also fp is set at 45psi idol with Aeromotive reg... Could the larger volume fuel lines have killed the walboro. Or could it be the C16 that its submersed in all of the time??? I looked at my metal fuel lines that came off the truck and interior of metal line is over twice as small as the 8an line interior. Im also gonna change fuel filter since I have never change since owning the truck. my bad!! This could be the issue? This seems to be a sudden thing that has just happened.. I dont recall any afr issues upon my last test drives.. Truck always ran really strong. Could this be another bad walboro? Also the pump seems to sound different when it preasureises when ignition is turn on. Truck will crank/ run and fuel preasure is running 40 on gauge whith line connected. Do I need a double pumper with the higher volume lines ??Any suggestions appreciated.

A little about the truck for those who dont know..Mods on truck are stock long block and cam. 61mm rpm turbo and downpipe, RPM edelbrock intake, 60lb injectors, fmic, RPM multichip tuned for c16 . 3400 3disc vigillante. Truck ran a 11.70 with a 3lb launch. 7.50 1/8th last time at track with bad conv and stock intake. Im estimating it should run 11 0s to a 10.90s with the new set up.. Truck now easily launches at 7.5 to 10lbs with the Vigilante. True believer is you get what you pay for when it comes to convertors. I paid 280 for my old 10 inch and it caused me a transmission + the cost of conv. + what was really bad, I couldnt spool the turbo past 3lbs!!!! with the el cheapo conv..
Still ran the 11.70 with it though..:D
picssy1531019.jpg
 

Quickstop [UK]

Combating adversyty.
Re: FUEL VOLUME issue!!

25 psi is prob a good point to have a double pumper with a hobbs setup, especially on 60 lbs.

-8 is big enough but shouldn't cause the pump to fail - maybe it is bad as you say. There was a batch of crap ones apparently.

You can actually calculate the volume that you'll need - not sure how personaly.

If it sounds different when you prime it, you've probably isolated it as the problem.
 

sy#2716

SyTy 4 Life
Re: FUEL VOLUME issue!!

how much fuel was in the tank? less than half a tank? i have some slosh issues with my 13 gal if it starts to get below half a tank i can watch the afr's vary more than on a full tank. I run less boost (14psi) than you but have a bigger combo. Last time at the track shindig it ran a 7.1@101mph.



I would either go with a double pumper(aeromotive just came out with a new pump with out preforms the walbro hands down) or sump the tank and go with a weldon or an a1000 with a controller(if it is going to be street driven any).
 

SYCLONE#1531

'MOFOFAST
Re: FUEL VOLUME issue!!

Ive still got the 20 gallon tank in it. It was 3/4 full. I was going to install my 13 gallon tank if I went with the dual pumps. I think ive decided to go ahead and install a Jaz 12 gallon sumped fuel cell (WITH FOAM) in the bed with a aeromotive inline pump. This should solve any fuel issues that will occur in the near future. + add a little more safety! Owe 7.1 is movin out pretty good! Turn up the boost a little more really and let it rip!
 

sy#2716

SyTy 4 Life
Re: FUEL VOLUME issue!!

Yea i was going to do a cell but i am going to either stick with the 13 gal and probaly go with a a1000 with a sump and then switch to e85.

The motor is back out now. IT cracked the #3 cylinder wall so i am putting the spare block that is going already have a short filled with 4 bolt main and same set up as the one that came out.
 

Beavis

Still plays with trucks
Re: FUEL VOLUME issue!!

I heard of someone else doing a similar conversion and had to add alot of fuel to the tune because of the increased air and air/fuel distribution. Also, upgrading the rest of the fuel system would be a good idea. You did half of it already, but the other half still has the same size and flow limitations that it did before the upgrades.

In my opinion, a new tank, Aeromotive pump, filters, and the rest of the lines in 8an like you did would give plenty of room to grow in the future and supply the need now too.

Keep in mind, any changes require a change in tune, and big changes require a big change in tune....
 

Quickstop [UK]

Combating adversyty.
Re: FUEL VOLUME issue!!

I think he means more generally that the upgraded fuel supply will allow troom for other upgrades that will require a tune.
 

SYCLONE#1531

'MOFOFAST
Re: FUEL VOLUME issue!!

the pump when it heats up is loosing preasure causing a stall sputtered out condition. . (I GUESS ITS ANOTHER BAD WALBORO.:rant: Also, all vacume lines are brand new and intact zip tied.. Ive got a 12 gallon sumped fuel cell on its way from summit. Also gonna run aeromotive 1000 inline pump with summit billet fuel filter.Hopefully ill get all the lines ran / installed from transfer case back this weekend. Any suggestions on the best location to mount the fuel cell? I noticed if i installed the sump over the rear dif, it could possible hit when suspension is loaded? I wonder if its legal and safe to mount the fuel cell on some rails to keep from cutting a large hole in the bed? This would keep the 2 inch sump ave the bed only requiring 2 holes for the fuel lines. Any suggestions appreciated..
tank13020.jpg
 
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Beavis

Still plays with trucks
Re: FUEL VOLUME issue!!

why would he need to change the tune? regulator and injectors will still be the same

The injecters are same, but the regulater is not, and the air supply drasticly changed from stock to edelbrock, which changes the air distribution heavily altering the air/fuel ratio. Thats why the tune will need to be changed. :roll:
 

SYCLONE#1531

'MOFOFAST
Re: FUEL VOLUME issue!!

The injecters are same, but the regulater is not, and the air supply drasticly changed from stock to edelbrock, which changes the air distribution heavily altering the air/fuel ratio. Thats why the tune will need to be changed. :roll:

Ill call RPM and see what he can do for a retune for me!
 

Beavis

Still plays with trucks
Re: FUEL VOLUME issue!!

You could try code 59 and retune yourself.....You seem like you could do it.
 

SYCLONE#1531

'MOFOFAST
Re: FUEL VOLUME issue!!

ive had to good of luck with my current tune to switch. Im not to computer savy! I believe Nolan is the actuall tuner for RPM.??
 
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