tscompusa

iTrader: (31)

** cars out of fuel - read below **

Zack wanted to post this himself with a review, but i told him to let me post it instead because i want to turn his results into a technical post & before and after.

While this stuff has been already known for years, a lot of people who are new will never find the posts most likely or still are not 100% sure what a single walbro really is capable of on E85.

id like to show just exactly where a walbro 255 unmodified (GSS342 part #) fuel pump is completely bottlenecked at on E85 fuel.

It seems that a unmodded walbro 255 has just enough pump capacity to support around 460-470WHP on E85. After that, it goes 13 afr~ uncontrollably.

The little snap shot of the fuel map shows how i had to richen the map the higher the RPM's traveled, which is the complete opposite how a normal operating vehicle responds / requires in the fuel map typically.

That all said, its not physically possible to make more power on a evo with stock fuel lines / fpr and a standard drop in walbro 255 hp fuel pump past 480whp on a dynojet. In this case, the car was completely out of fuel by 460WHP ish.

Mods:

fp red 64mm jb (25psi wga)
hks 272s
walbro 255 (soon to be modded / major bottleneck atm)
hallman mbc / grimmspeed 3 port / 4bar
forge bov
fic bluemax 1050cc
3" tbe hks carbon ti/ no cat no resonator
3" turboxs FMIC
map o2 housing
Tephra v7 maf / hybrid boost


Below is the graph.



Im having him pull the pump and replace the fuel sock + mod the pump and i will show a before & after results of what the modded fuel pump does with details to go along with it.

(93 results not shared. car made a hair over 400whp)




Results after fuel pump being modified:



nothing was done to the car other then modifying the fuel pump. we decided to leave the same sock in there to not jeopardize the results of the
back to back comparison. the tune was completely untouched.

Final test results:

Unmodified the walbro can support roughly 440WHP on e85 fuel.
Modified it can support roughly 480WHP with 12.5 AFR

what will it do with a larger feedline????

mitsubeastlee

iTrader: (3)

damn a wally 255 can take you pretty far on e85, how much further do yo think an aeromotive 340lph will take someone? well over 550whp I presume?

tscompusa

iTrader: (31)

https://www.evolutionm.net/forums/10664476-post1.html

the walbro 255 once modified will support the same power as the aeromotive 340lph, which if i had to guess i would say it will not go past 540whp dynojet on E85.

to be safe, id say i wouldn't expect it to go much past 520WHP dynojet.

Based on the results i just shared + the data in the post i linked just now, you can figure out how much power technically it can produce vs unmodded vs modded since i shared the LPH/performance of the pumps modded vs unmodded.

I'll post back here with the results right after he mods the pump with absolutely no rom modifications at all so others can get a true idea of how much effect the mod really effects the fuel pump and what it is truly capable of once done.

(maybe we should use the same fuel sock just so that doesn't effect the before/after of the actual mod)

evolved0414

iTrader: (5)

I would like to share with the entire evom community my experience with Tom from Tscompusa. A little over 2 years ago I decided to make some decently major upgrades to my car. I was already tuned by a reputable tuning shop so of course I was considering on going back to them for my re-tune once my mods were installed. Now I have been checking the dyno section of this forum since I've had my car and I happened to stumble upon VRSF speedfactory. I sent them a message only to be replied back immediately by Tom. He was the most confident tuner I had pretty much ever talked to. After listening to Tom's amazing knowledge of tuning, I knew I had to give him a shot.

Now 2 years later Tom is continuing to tune my car except this time with the 3port/omni 4 bar hybrid boost setup. This guy takes above and beyond to a COMPLETELY different level. He has spent numerous hours on my car and would not give up on me until he knew I was getting the most out of my car. No other tuner would do what Tom has done for me, hands down. Most other tuners would have just tuned my car as is and accepted mediocrity. After countless emails and instant messenges we have arrived at the results you see above. You will NOT find another tuner who does his job not just for the job, but does it for the passion of tuning. I can't wait to finish up the e85 tune and post the final results!!

JohnBradley

iTrader: (30)

One pump and 1050s I am pretty sure I was 105% at 459. It was an EF3 car, I checked the fuel for ethanol level (E85), and had modded the pump (punched the relief). We ended up going to a double pumper and dropped something like 25% IDC for the same power and then went on to make 500whp with fuel to go....all on the same injectors.

Nice to see that you got repeatable results and I wasnt just crazy

CT9Asphixyation

iTrader: (3)

Have you found out at what point the Walbro 460 reaches its limit on stock fuel lines as well as aftermarket ones?

DisgustipatedM3

iTrader: (2)

Great results, Tom. I knew I'd have to modify my Walbro 255 before going for 500 whp on the new turbo... I'm just going to do it beforehand. Can't wait to see your before/after comparison.

itsmrrizz2you

iTrader: (14)

nice... cant wait to finish my tune!!!

tscompusa

iTrader: (31)

awesome review thanks Zack! Pleasure working with you.

Good info also! Thanks for sharing that Aaron to confirm/backup my results also on a real dyno. he should put in 2 pumps, but were going to see what it does with one modded first. I am guessing it wont go past 520 (i dont think the mod list will allow that anyways though).

I haven't personally. I am willing to pay for the flow test if someone wants to ship one to kinsler and get it tested though. I think you mean the 416lph right?

Thanks. it should go over 500 once modded. (hopefully). the HKS cams suck. hopefully i can just squeeze more boost uptop to make up for there lack of power capabilities. don't really wanna go past 30psi though.

i don't see a log yet from you in my email.



=====================

i found another good test by another shop with a aeromotive 340lph which is basically a clone of a modded walbro 255 as far as flowrates go.

http://www.trueevo.com/forums/showth...-500-WHP-EVO-8

looks like its done by 520whp (with sane AFR's). that's still respectable for one single pump though.

this just shows the walbro 255 is still a badass little pump! mod it and it keeps up with all the rest of the high flowing ones ~340lph ones.

long live the cheap walbro 255

car_nut15

iTrader: (8)

Should the walbro be modded when shooting for 500whp on pump gas or does this apply to e85 users only?

badev0

iTrader: (74)

Great info for sure. Tom puts a lot of time into testing things to help his customers.

I think this might be the route i'm going to take on my daily driver after seeings mods/results (FP red, same cams, single wally, and similar sized injectors).

heel2toe

iTrader: (41)

Thanks for sharing this info, I am excited to see what can be had once the pump is modded. It appears that this car was running 28# in its current state?

What were the IDC's for for comparisons sake; I would like to see how it changes before and after?

Im curious, at what point the injectors would be maxed out using the stock lines FPR and wally 255 both stock and punched. I guess there isnt one answer bc the amount of boost the car is running will have an inverse affect of fuel flow but ball park figures would be nice.

Also, any reason the fuel sock is going to be replaced or is it merely just because you are already in there and figured you minds well?

Thanks for doing this and I look forward to seeing the results!

tscompusa

iTrader: (31)

I would do it yes. it drastically will help you if you are running anywhere around 30psi of boost, which on a stock fpr will set you roughly right around 75psi of fuel pressure. i have back to back from non modded to modded on 93oct with a large setup on 93oct, and it went from going lean to rich. I just cant remember what the customers name was. ill have to dig into folders today for it.

ya this is a good route, however i would do the kelford 272 or s1/s2 minimum. hks 272 leave to much power on the table to be had for me to recommend them.

no problem! glad to share it and help educate others on what the pump does once modded and where it gets bottlenecked at.

if you look at the flow rate between the two pumps here (340lph aeromotive + walbro modded) you will notice at 100psi they are identical in performance.

GSS340 (walbro 255lph rated hp modified relief valve)
50psi: 242lph - 8.1 amp
70psi: 208lph - 10.4 amp
100psi: 153lph - 14.6 amp

Aeromotive Stealth 11142 (340lph rated)
50psi: 284lph - 12.7 amp
70psi: 228lph - 14.3 amp
100psi: 155lph - 16.9 amp

this vehicle is going to running around 75psi of fuel pressure. we wont pass 30psi of boost most likely at higher rpm due to the fp red being to small of a turbo to keep up.

that puts us in a spot where the 340 aeromotive actually has the advantage based on the flow testing done at kinsler at the set voltage of 13.2v. not sure whats going to happen in real life on the car with the stock fuel lines + stock rail + stock fpr, and so forth, but we are about to find out soon.

its possible it may get stuck around 490-500whp and run out of fuel again, making it completely necessary to go to a dual walbro to proceed further, but im sure in this case it will give him just enough additional fuel flow to make him happy and leave it where it is finished off at one pump wise. Thankfully its E85, so i can run it alittle on the lean side, favoring our results and the pump. I wont take it past 12.5 though as a finished end result.

i guess the question is, how much is 20lph of fuel flow worth in our cars? that seems to be what the aeromotive has the upper hand on at lower boost pressures. not that 30psi is low, but they dont start evening out until around 50psi, which is pretty far off from 30psi.

there's other things to take into account, but i dont get into it that detailed. mrfred will though if you ask him to.

I was gonna sell him a new fuel sock, but after thinking about it, it could skew the results if the current sock is alittle dirty. the new sock could flow better, so we are not going to replace the fuel sock at this time.

but i would really suggest replacing the sock anytime you ever have to get in there and remove the pump, its just extra reassurance, and the less restrictive / clean the sock is, the less the fuel pump has to work and will keep it running healthy and have a longer lifespan. a lot of walbros whine and die from fuel socks being clogged/dirty, and the pump gets blamed for it.

in regards to the IDC, we do not log that during the runs because it takes up so much logger resolution, that it would actually inflate the vd #'s. I can have him do a run with those logs after were done today though (if he gets the mod done).

mrfred

iTrader: (50)

Tom, I'll be surprised if you can get more than 500 whp by punching the relief valve. You've got to contend with higher back pressure on the pump from higher fuel flow, and the factory wiring may not be able to supply the same voltage at the higher pump demand.

evolved0414

iTrader: (5)

I will be doing the walbro punch relief today. As tom said, hopefully punching the fuel pump will be enough to get me that richer mixture I need and past the 500whp mark!