CR00SS

Just wondering how much boosted horsepower a single walbro 255 with hotwire kit and 60lb or larger injectors will support! I have seen a few 500rwhp+ with walbro and 42lb injectors on sts type kits and supercharger setups, I`m just wanting to know how much this application could truely handle before purchasing my fuel system! My car is a 00ss with 370 (currently building) ls6 cam stock 317 heads iron block based! tc76mps with big air to air intercooler th350 w/4000 vig stall and 3.23 or 3.42 gears 10 bolt for now 9inch later just want to get everything running. I want to make a 550-600rwhp reliable daily driver! I know I could build a cheap twin intank kit but the ones I have seen, the buckets look hacked up w/ lots of rubber hoses with tight bends and unstable . I don`t want to have to do this but once so anyone with pics which would be helpful and prices of their clean budget (if that makes sense) fuel systems feel free to post.

SR-71 SS

iTrader: (2)

my 255 with 60's didnt carry much past 500 with a procharger, ended up going with a aeromotive a1000 pump kit. a bit overkill for my application but i would rather have a comfortable overhead for later mods.

tha joker

iTrader: (5)

my 255 and 60's went to 650rwhp with my maggie and 50 shot

koolaid_kid

iTrader: (21)

I am confused on this issue. Why is the range so wide? This is not the first thread where I have seen such a disparity.
I currently have a Racetronix kit with the Walbro 255, an STS which will be running 8 punds of boost, Stage 2 meth system. Currently running 42s, but I have a set of 60s in the wings for my forged turbo engine (fully built, cam, heads, intake, tb, the works). If the pump is the limiting factor, I would probably stick with the 42s. If not, I would go with the 60s.
That's why I am confused when I see such differences being reported.

93camaro_zzz

iTrader: (13)

My friend had an 76mm STS kit with that setup, and he maxed his car on the dyno at like 5500rpm and had 535 to the wheel at that point.

Nasty N8

iTrader: (33)

Because each setup is a bit different.....tuning,blower,turbo,motor,different fuel...your meth will act as a patch for not enough fuel. The Walbro 255 is only good for about 500-550rwhp on a boost car as are the 42# injectors. Now if you can boost ref. that will also help up the power handling.

Nate

NicD

iTrader: (7)

Pretty much every turbo car I have seen with just a 255 upgrade and 60s will hit around 525-550 rwhp with the pressure falling off up top a bit on 6 spd cars. A KB boost a pump seems to push that out to around 600 rwhp pretty reliably. Through an auto it will be a bit less.

ZL1Killa

iTrader: (17)

No, the range is so wide because a 255 pump maxes out at a 51lb/hr injector (flow wise). You can then do the BAP (boost a pump w/racetronix and get a bit more)

it is best suited to go with a 340+ L/hr pump or higher with anything above 42# injectors rated @ 43.5psi.

I promise that there is a method to all this injector madness. It is a system, you have to have a pump capable of providing fuel to your injectors and you have to have injectors capable of providing fuel to your engine.

There are a lot of people that don't realize and don't look here:
https://ls1tech.com/forums/fueling-i...alculator.html] -it has changed a bit over the years too

I luckily got that stickied and "onfire" found some more information and put it up there for all of us, I believe it should be bolded so more people see it but it may not work any better.

koolaid_kid

iTrader: (21)

While it appears that you explain the upper limits, I'm not quite sure how your answer explains the range. Pehaps I missed something. And I have visited that sticky so many times it's not funny.
Digging further, I went to RC Engineering and entered some values. On the Fuel Injector Worksheet, I entered 620 hp, 8 injectors, bsfc 0.50 (N/A) duty cycle 0.80, FP 58 psi. It says 42lb injectors would be fine.
For F/I, bsfc of 0.60, 625 hp, 51lb injectors should be fine.
So, why is everyone (except one) reporting lower numbers?

Of course, there is always the air pump issue. We know our engines are merely a glorified air pump. If we can't pump enough air, it does not matter how much fuel is available, the excess will not be used.

Just trying to get a handle on this issue, not trying to start an argument.

ZL1Killa

iTrader: (17)

the only thing I can figure is what you are saying about airflow.... higher flowing heads/cam so forth probably yielded him those good numbers.

But your fuel pump must be able to support your injectors... so the question is what fuel pump & injector combo are they using along with what heads/cam setup and so forth