LS6427

iTrader: (2)

Curious....

During a 1/4 mile drag race OR during a Hard roll race.....

If the pump fails.....what happens to the engine?

Does it get damaged?

Or does nothing bad happen and you simply roll to a stop?

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Nostang

iTrader: (4)

If you are close to stock and N/A you will probably be fine. If you are running boost or nitrous there is a good chance of popping a piston. A complete failure of the pump would be less prone to causing damage than losing pressure slowly and staying in it. Every situation will be different. You could wire a fuel pressure safety switch to monitor fuel pressure and some trick wiring to pull timing, boost, or shut of the n20, trigger a dash light, etc.

LS6427

iTrader: (2)

This will be an approx. 1,100 RWHP boosted roll racer. 20-21 psi boost from a Positive Displacement Supercharger.

I'll be using the P59 PCM....maybe my tuner can add a fuel pressure sensor that will let me know if its failing. That solves the slow decrease of fuel pressure issue.

But if it fails quickly and just dies.......is there anything that can be added to keep the engine safe? Or will it simply shut off and no damage can occur?

I was thinking of using two large fuel pumps, where either pump can handle the 1,100 RWHP all by itself......in case one fails during a hard run. Not sure if thats something that can be done.

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Zmg00camaross

iTrader: (11)

LS6427

iTrader: (2)

OK. Can a sensor be put in to monitor fuel pressure and if it drops below a set number the engine shuts off instantly? Therefore, if the pump instantly dies or if it slowly dies....the engine is 100% protected?

Or I guess a simple low pressure light comes on and you lift off the throttle to idle......that should also save the engine 100% if the pump fails either instantly or slowly....correct?

I think it would just be easy to just build a fuel system using TWO of the same model pump.....either one being able to supply max power and WOT runs. So if one fails the other keeps going and nothing bad happens. But I keep hearing from fuel system builders that I shouldn't do that. Maybe because of too much pressure with two pumps running.....????

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LS6427

iTrader: (2)

Also....how does an engine burn up if the fuel completely shuts off instantly.....pump instantly fails. Where is the heat coming from at that point to hurt the engine....???

I understand the slow dying pump, getting leaner and leaner........but if it just stops, the engine should just stall and roll to the side of the road....Right...?

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pdxmotorhead

if fuel just stops,,, so does the motor yes, but depending on how its plumbed there can be residual pressure in the lines, so you might get a couple pops out the exhaust
That being said its REALLY REALLY abusive on a engine to go from full throttle to nothing,, I have seen it
crack pistons...Playing with yard engines we figured out you can turn a stock 350,,,
really really fast without breaking it. the blow when you let go of the power..

Fuhnortoner

tap a pressure switch to the fuel rail and wire it to disconnect power to your solenoids when its activated.

LS6427

iTrader: (2)

So engine will just shut off?

Is that ok while at 6800 rpm?

I don't see why using two pumps that run together, both of them being able to handle the WOT is a problem...........then if one fails during a WOT run nothing happens, the hard run continues......NO??

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Fuhnortoner

This is all IMO, so take it how you wish.

I dont see a problem with shutting down the engine at 6800.

I also dont see a problem with using 2 pumps. In fact, I recommend it. And if you want triple protection, add the FP switch like i said in the post above.

One thing for sure though, with a low fuel pressure light, youll most likely never be able to lift your foot in time to save the engine.

LS6427

iTrader: (2)

Ok, I'll call the guy building my fuel system....get a price for a dual pump set up. And that pressure switch.

Thanks.

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LS6427

iTrader: (2)

Another idea...

How about two pumps...both are capable of handling a WOT run. But only one operates under normal driving conditions. Then #2 pump comes on under a certain amount of boost.

Is that easy to set up?

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Fuhnortoner

Been done many times. Search.