My 383 should be around 450-475 hp. With some later port work/tuning it'll probably be right around 500. I then plan on going with a 150-200 shot. The motor has a single plane with multi port injection and a 1000 cfm 4 valve throttle body.

Do I need to replace my fuel lines with bigger ones? If so, what size?
I was planning on going with a walbro 255 ltr/hr pump. Is that enough, or should I go with an external instead?

I was planning on 30 lb injectors, but should I go ahead and get 36lb ones since I'm gonna be spraying?

 

I'm doing mine in 1/2" AL tubing I thought since I was replacing the tank, and installing a fuel cell I might as well do the whole F'in thing, and not look back or think about weather 3/8 can handle future upgrades. The cell is plumbed with 1/2 & #8, and I have the engine plumbed with #8.
btw: #8 braided is a little smaller then 1/2", but not much.

I still need to find a 1/2" tube bender!!! Haven’t really looked lately cause it's been to coldddd.

I would think 1/2" would be good for 800+ HP...It's BIG.

Ron

 

1/2 aluminum tube is the way to go along with AN fittings and braided lines for the flex connections. i'd mount a inline filter, like one from fram.

 

-10 or 1/2" would be my minumum for a 500hp motor, the fram filters were nice awhile back, but you should consider a bigger pump naturally to feed the beast and fend off a lean condition, but the problem with the fram canister type filter is that it doesn't allow enough gph flow when used with a big pump. I can attest to this, the S-10 I drive has a 555hp 383 with -10 from the cell to the carb with a holley black pump and Summit canister filter aka Fram and I keep experiencing a flat spot on the top end. First thing that went was the filter since I've personally laughed at the idea of a 140 gph pump being restricted by a 90gph filter? We upgraded to a Holley 750GPH filter and instantly picked up .02 in the 1/4. This helped but towards the end of the season it still felt like it hit a flat spot so we bought a fuel log, havent had a chance to test this set-up yet but hopefully the extra reserve of fuel will help make it the last 300' or so with no flat spot. I'm only hitting 7200 at the first shift which is fine but at 6900 on the big end is where it gets kinda ify. We tested the fuel pump output and that was fine for this little of a motor so the little details will get resolved once the track opens back up in the spring.

 

Yea, this is the one I was looking to use myself...Holley #162-517

Ron

 

from what i hear 3/8 line will support 500 HP max, and if $$$ is a big deal you can probably get away with it, but i would recomend upgrading. and i would also say get a bigger fuel pump.. i dont know too much bout the 255 so maybe its ok, but i would get the aeromotive pump that supports 1000 N/A HP its not much more, as for the injectors if you already have the 30's keep em, you can always turn the pressure up a little higher if needed, but if you haven't bought any yet then i would suggest getting whatever is recomended for 500 HP, there are charts/formulas available to find the correct injectors on another note shooting nitrous has no effect on the injectors unless its a dry system (JUNK!!!) if its a wet system then the nozzle(s) or plate will inject the extra fuel, your fuel pump will have to be able to handle the 650 HP (500 +150 nos) but injectors only need to be good for 500 HP or else they will be too big

 

That looks familiar

 

btw: That was the best damn filter I could find researching a while back.

Oh, and If a fuel log doesn't help you, I would guess that problem lies else where!!!

Ron

 

Depends on whether we are talking about 500 flywheel or 500 rear wheel.

If we're talking 500hp at the flywheel then all you need is a Walbro 255ltr/hr intank fuel pump. Stock everything else. I'm pushing about 400hp to the rear wheels (500 to the flywheel) and that's all I am using ... stock fuel lines with an intank Walbro pump.

Tim

 

How difficult was it to drop the take to change the fuel pump?


I seen someone here on the boards cut a square out of the body (right over the top of the in-tank pump) to make a quick change of the fuel pump alot easier. Then re-attached the square and made it to where it was an attachable/removable peice.

 

it's not that difficult. the biggest thing is dropping the rearend. unless you have a stock style catback exhaust, then you gotta pull all that out too. i didn't have to worry to much about that though, i am running true duals that dumps infront of the axle. anyhow, once you get the rearend dropped(not all the way out of the car though) it's pretty much a strait-forward deal

 

I know we're gonna go from the current 4.30 gear to a 4.56 or 4.88 to get teh revs up at the finish line as we're not using the whole engine for the entire pass, plus we're installing new Stahl headers since these hooker super comps are a joke for this S-10...get this- 1 5/8" pri. & 2 1/2" collectors? WTF were they thinking, so the Stahls are 1 3/4" with 3.5" collectors so it oughta breath much better. So with the bigger revs on top, better breathing, if the fuel log doesn't eliminate the flat spot I'm thinkin of hooking up a voltmeter to the pump for a pass and see what it says, maybe run some 8ga wire to it for juice or just get the Aeromotive pump that I plan to install on my car on this instead and see what happens. Cant complain as it's a deadly consistent flat spot, usually the truck only ran maybe .004-.006 from morning to night on the dials, but for the weight and the power it should be going faster, high 10's just aren't cutting it when it should be easily mid 10's in the summer and 10.40's or better in the spring/fall.

 

Mine hp ratings I give are at the flywheel, but with n2o being added....I guess I'll go with a pump bigger than the 255.
I'm wary of using aluminum lines on a street car.

 

I'm kinda on teh fence for the aluminum line issue. If used in a spot where absolutely NOTHING has a chance of hitting it and it's insulated from vibration it's fine, but we had a guy start his engine bay on fire last year when the alternator belt broke and slapped the line. He had just finsihed looking stuff over in the pits and was walking away from the car and then POOF, musta had a haair line crack that gave way and spewed gas straight on the hot header, damn lucky we got it out in time and thankfully he was finsihed under the hood when it happened-coulda been real ugly. As for my personal car, nothing but -10 braided from back to front, spendy but pretty

 

Oh yea those headers are a bit small to evacuate the exhaust at that rpm! It should breath much easier with 1.75"..."high 10's not cutting it!"

As far as the fuel line material, I'll be running mine inside a steel pipe along the bottom.

btw IHI, talking about looking familiar.

Ron