WHY WOULD YOU WANT TO RUN A MECHANICAL FUEL PUMP IN THE FIRST PLACE?
How many times have you bought a speed part, only to find within a short period that it becomes "obsolete", can no longer fit the purpose you needed it for...or simply, you outgrew it faster than buying clothes for a 3 year-old? When using a mechanical fuel pump (MFP), those days are long gone as the chances are very slim you would outgrow what these kind of pumps can provide. Need more fuel? Run mechanical. You're done. Possessing the Waterman Ultra Light Sprint pump we offer can supply enough fuel for up to (8) 2950cc injectors is good to have! Thousands of horsepower supporting.
Yes, you read that correctly...thousands. The best of the best run MFP's and it's no mystery why. From sprint cars to funny cars, and weekend warrior drag cars to asphalt-pounding street monsters ...you'll find MFPs feeding these hungry beasts.
And speaking of high horsepower supporting, the faster your motor spins, the more flow you get with mechanical! Fuel curves are linear with engine RPM. Not so with electric. Once they've hit their flow limit, they're done. Add to the fact of the excessive load (and heat) that is created by an electric pump at full capacity...and that robs precious horsepower. It is also not uncommon on race cars to not need an alternator once an MFP enters the picture (as an electric pump is the single largest draw on the battery). Your biggest worry on battery load, chances are, will then be your rad fan. 🙂 Yay!
You also will increase the reliability factor in your fuel system. No relays to go out, no pressure switches, no fuses, no wire breakage, no bad grounds, and no circuit boards. NONE of these factors to fail which could very well muck up that record-setting run. Or even worse...destroy your motor.
THE CAVEATS OF RUNNING A MECHANICAL FUEL PUMP
If your fuel tank is in the back, and in order to use an MFP, you will need a primer pump (ran in parallel) to help bring the fuel up to the MFP and start doing its duty. Of course, this doesn't have to be a huge demanding pump...only to supply adequate pressure to the squirters in order to fire the engine off. Once ignited, you can de-activate the "primer" pump. Move over Rover...and let Jimmy take over.
To make things easier (and more economical), you probably already have a cheapo depot electrical pump laying around because of all the upgrades you've made throughout the years in your quest for rockstar drag status. A surge tank might also be a requirement in your application if your 60 foots are less than 1.3. An absolute requirement if you see the sky when launching.
If your cell is up front, then the fuel line run *might* be short enough to not dictate the necessity of this primer pump. The Waterman Ultra Light Sprint pump we sell is very forgiving in this regard. Just a shot of starting fluid is all that might be needed to fire it up.
As long as there is fuel present in a MFP, then it's a pumpin' mutha that doesn't care how big your GF's ass is. Got no fuel...then it's a dead slug. The issue is exacerbated with larger lines. A little more work to move that heavy slug of fuel through the line and up to the pump. It sucks to have no suck.
All setups are different...all situations are different. You just have to see what YOUR car likes and make it happy.
THE SAFETY FACTOR
To get right to the point, MFPs are a safe bet...literally. At least safer than electrical...if heaven forbid, something catastrophic happens. Picture this. Your engine grenades (or whatever else that causes your engine to stop running) but your electric pump hasn't figured that out yet. An electric pump will still keep running, shooting fuel in places you wouldn't like. What if a fitting comes loose? What if the hose bursts and hits that glowing orange, fancy long-tube header? What if? What if?
All of this isn't a good scene, and certainly not a practical method for making a bonfire for chips and beer consumption. A MFP will only pump the fuel if the cam is turning...which means only when the engine is running. Right there alone was enough to sell me years ago on what I would do for fuel delivery as I have no ambition to become a Post Toastie. I don't even like the possibility of it. True, lots can happen beyond our control, but we can certainly decrease the odds of it happening through making educated and well-informed decisions.
End of story.