Carbureted LSX forum - Electric fuel pumps? also plug wires?

I was wondering what kind of fuel pump and regulator to get. I have a 5.3 with ~400hp going into a G-body. I don't know what size fuel line is on the car, but is there any reason to get a larger line?
I want to use a separate pressure regulator so I can run a return line (which the car has already from the goofy charcoal canister). Should I mount the fuel pump to the frame in the rear and maybe mount the regulator on the firewall?

Also need to get some plug wires that will work with whatever headers I get. I tried to buy some Taylor angled wires from some goon on Ebay and barely got my money back... Throw me a link if you got some you like.

Any advice? Thanks!

Other items on the list:
Lokar LS1 dipstick
Steam vent o-rings
Block hugger headers

Did the g body have fuel objection and if so was it a stock fuel pump in tank or a hp one?
If so you can run keep it and put a good regulator and return line reducing it to carb psi of 6 psi. I am going to use my walbro 255 LPh inline pump that I had with fuel injection on my carb setup. 3/8 line feed and return is what I will be using.

As for plug wires I run duralast from Autozone. Life time warranty and with plug wires so short there is no reason to buy bigger wires. I data log all the way to 7500 rpms with auto zone wires with zero ignition break down and 11.75/1 compression. Save your money.

Anything from Aeromotive, Holley, Mallory, etc will work. I use a 140gph Aeromotive pump.

Pump should be mounted as close to the tank as possible and lower than the bottom of the sending unit.

Pressure regulator can not be mounted to the firewall per NHRA rules, but you're on the right track. Mount it to the intake or the frame as close to the carb as is realistic. Not terribly critical though.

Be careful using the lines from the charcoal canister. Most of the time they are baffled at the fuel tank and will prevent you from running the correct fuel pressure.

Be careful using the lines from the charcoal canister. Most of the time they are baffled at the fuel tank and will prevent you from running the correct fuel pressure.

Isn't that what that line from the canister is? A return line? How would that effect fuel pressure?


As for plug wires I run duralast from Autozone.

Thanks, I'll check them out. The car was originally a carb'd setup with a mechanical pump on the block

The line to the canister should only have fuel vapor in it, not raw fuel. It is only a vent for evaporated fuel from the gas tank. It is NOT a return line of any way shape or form.

OK thanks. I'm still learning.

I might grab a Grand National fuel tank and in-tank pump setup I was reading about. That would be kinda fun to do.

http://www.summitracing.com/parts/CRT-P4070/

^ I would use this pump right here for a 400hp 5.3. It will have enough pressure but won't need a regulator and its rotary design is nice and quiet.

its rotary design is nice and quiet.

Really? I know the Holley makes some noise, but not so much that i would hate it. If this one's even quieter, might be worth a look

You would be wise to get a low resistance plug wire such as the MSD Super Conductor (50 ohms per foot) or something similar. Most factory or generic plug wires are in the range of 500-900 ohms per foot. Less resistance means a stronger and more consistent spark to light the air/fuel mix.

You would be wise to get a low resistance plug wire such as the MSD Super Conductor (50 ohms per foot) or something similar. Most factory or generic plug wires are in the range of 500-900 ohms per foot. Less resistance means a stronger and more consistent spark to light the air/fuel mix.

Plug wires are a foot long , no hp gain whatsoever .

Plug wires are a foot long , no hp gain whatsoever .That would be incorrect. A stronger and more consistent spark is going to make more power. It won't be a big difference but there IS a difference.

You would be wise to get a low resistance plug wire such as the MSD Super Conductor (50 ohms per foot) or something similar. Most factory or generic plug wires are in the range of 500-900 ohms per foot. Less resistance means a stronger and more consistent spark to light the air/fuel mix.

That would be incorrect. A stronger and more consistent spark is going to make more power. It won't be a big difference but there IS a difference.

I have data logged runs to 7500 rpms that shows no signs of ignition break down, I don't think his 5.3 will ever have a problem. On my Trans am I changed to accel 8.8 wires and was excited to go back and run them. Nothing was gained.

"Plug wires make horsepower". More like horse-shit. If they transmit the minimum required voltage to cause a spark hot enough at the correct moment without interference, the cheapo wires will work just as well as the expensive wires that transmit an even higher voltage without loss. There is a point of diminishing returns on quality of spark, and our stock ignition is already at that point. There does come a point where dynamic compression ratio at the moment of ignition needs a better charge than the stock wires can supply, but we are no where near that with our motors. It used to be true that 3 foot long wires using a single under-powered coil would benefit from a better coil and lower-resistance wires in a stock application. With our individual coils and super short wires. It doesn't matter. At all. In any way.

That said, the wires in my used LQ4 needed replacing and I went with MSD wires. Mostly because they look better and I like the angled connectors to clear my headers. They won't help me make any more power. Not one iota.

I'm running a Holley Black on my car

http://www.summitracing.com/parts/CRT-P4070/

^ I would use this pump right here for a 400hp 5.3. It will have enough pressure but won't need a regulator and its rotary design is nice and quiet.

+1

I am running a 140 gph Mallory gerotor pump with their matching return style regulator on my 440 HP LS2. It is really too much pump. Better too big than too small, but the bigger the pump the noisier it is. The way mine in mounted it is very noisy.

Isn't that what that line from the canister is? A return line? How would that effect fuel pressure?



Thanks, I'll check them out. The car was originally a carb'd setup with a mechanical pump on the block
Don't try to use the line from the charcoal cannister for a return line. It has a restriction in it where it goes into the tank and can't flow fuel fast enough without modification.

Don't try to use the line from the charcoal cannister for a return line. It has a restriction in it where it goes into the tank and can't flow fuel fast enough without modification.

OK, I decided to get a returnless type pump with a built in regulator, probly the one stunningman said to get.

I just have to figure out which of the lines from the tank that I can plug, and which one needs to be vented so I can get rid of the canister all together

OK, I decided to get a returnless type pump with a built in regulator, probly the one stunningman said to get.

I just have to figure out which of the lines from the tank that I can plug, and which one needs to be vented so I can get rid of the canister all together

Use ethe 3/8", vent the 5/16" and plug the 1/4" if your car has it.