38 replies to this topic

[LXCHEV]

Hi guys,

Interesting topic this one. What do people think of retaining mechanical fuel pumps on vehicles that see some drag racing action?

Ie. I'm basing this example around cars with approx 400 - 500 HP (or even slightly more), that run, let's say 12's and 11's down the strip..... even heading towards high 10's....

With Small-Block Chev's, you can get huge 6 valve mechanical fuel pumps.... it's key that you give them a good volume of fuel supply (1/2" line and 1/2" pickup in tank).... but these type of pumps are rated very highly.

My engine builder says yes these pumps are ok, but electric pumps are definitely the choice for drag racers.....

The reason I'm thinking of going back to a mechanical pump on my 383 Chev is to get rid of the annoying electric pump noise.... it's also one less thing to have to worry about... ie. the pump getting hot near the exhaust, less wiring etc....

Another engine builder told me they run these mechanical pumps on blown smallblocks making 600-800HP....

Would love the hear some thoughts / experiences....

Cheers all.

Edited by LXCHEV, 20 March 2007 - 09:47 AM.

[LXCHEV]

Thanks for your comments ChevLX, that's great to hear about someone running one, and running 11's.

With the blown ones - yes I was still referring to the standard mechanical pumps (cam driven). I realise the belt driven ones are for when you really start getting serious... but this particular engine builder definitely said they had blown SBC's running the cam driven mech pumps, with no probs.

Keep the comments coming guys!

[TerrA LX]

i think the noise is more the design style of the electric pump and the way its mounted. There are different ways the pump is engineered that are noisier than others.
dropping the pipes before the mufflers also helps overcome any pump noise.

[Struggler]

I was running 11's with a Holley chrome pump (NOT the hi vol one either) with no problems at all.

With my last upgrade I swapped to electric for only one reason, as I don't drive this thing regularly the fuel in the bowl evaporates and I would be cranking it for days to get fuel back up to the carb. A half reasonable mech. pump will be fine. I know for a fact a full pair of Holley float bowls will get you to half track before leaning out. Any mech. pump should be able to recover from the initial launch and maintain the fuel level from there !!

There are heaps of advantages to a mechanical pump in a daily or regular driver (quiet, reliable, no fuel pressure when the engine stalls etc). I would have used the 6 valve Holley pump but it ended up in the same place as my steering box. You wont have that prob. in a LX.

Hope this helps.

[LXCHEV]

Struggler, exactly the kind of info I wanted to know!

That is very, very interesting about the full fuel bowls on a Holley type carb being able to cope to half track, that is incredible! Have you had a certain experience on the strip where this happened to you or something??

Either way, I did actually have one of these 6 valve pumps feeding the Chev years ago.... but back then I was running a Quaddy.... obviously a Holley/Demon type carb has 2 fuel bowls, each of which is twice the size of a Quaddy bowl... thefore I now have 4 times the fuel readily available.

I am liking the sound of going back to a 6 valve pump more and more now!

Any difference between the Holley 6 valve and the Edelbrock 6 valve??? Or are they one and the same?

Here's a link to the Edelbrock pump... 130gph, standard with 1/2" fittings too:

Edelbrock Victor Series Pump



Should I consider any other brands??

Struggler, thanks again for your detailed feedback! Absolute champ.

[LXCHEV]

Just got a price on the Edelbrock ones: $148.70 + gst, therefore $163.57 total.

Rocket Industries say Holley are no longer making the 6 valve pumps, so it looks like Edelbrock is the go.

[LXCHEV]

Not yet... but I definitely will see what I can find on them.

[Struggler]

That is very, very interesting about the full fuel bowls on a Holley type carb being able to cope to half track, that is incredible! Have you had a certain experience on the strip where this happened to you or something??

Yep, staged the car, went to turn off the thermo fan and turned off the pump by mistake !

Carter do make a 172GPH pump, check it out here... http://store.summitr...15&autoview=sku

Holley also make one, this is the pump that crashed into my steering box, it is the same pump used in the Winston Cup in the US .... http://store.summitr...15&autoview=sku

I got the Winston Cup pump from Rocket about a year ago, give them a call with the part number. Both of these pumps don't look like the old style 6 valves, however they DO have 6 valves inside them.

[Struggler]

Also have a look at the lightweight fuel pump pushrods.... http://store.summitr...01&autoview=sku

I weighed a stocker and this unit was 1/2 the weight. This helps pump and camshaft life.

[LXCHEV]

Mmmmmm very nice indeed.... both those pumps look sweet. I love the way the body rotates and the fittings.... awesome.. definitely want to go for one of them now over the Edelbrock one..

So what would be your preference for a streeter with my combo then Struggler? Carter or Holley? 130gph or 170gph? Since you bought the Holley one recently, I'm guessing you like the Holley ones? I'm sure either pump would be awesome.

PS. Also like the sound of the light weight pushrod... excellent idea. I think that will be added to the shopping list too.

Yikes, looks like another revamp of the fuel system... again.... hehehehehe

[Struggler]

Yes, I prefer the Holley, just because its cheaper to locate locally.

The eBay item is the pump I originally used, good for high 11's. It does NOT flow 150GPH though, more likely 90GPH.

[Stedz_lc]

Could of mentioned this before i went out and brought an aeromotive elec pump!! i would of offered u money on your carter pump brett, ah well it happens

[LXCHEV]

Hey Ed... I don't think I'll be changing back to mechanical real quick anyway.... very hectic at the moment.... plus I have the 2 drag days in April.... so might still do them with the Carter electric pump... then afterwards I can strip my fuel system down and convert to mechanical at my leisure!

So I think I'll aim to do this during May...

[ls2lxhatch]

A couple of interesting pages.

http://www.hotrod.co...el_system_tech/

http://www.aeromotiv....com/system.php

[LXCHEV]

Ok here's the latest research.

In the Holley range, you can get 110GPH, 130GPH, 170GPH, and 170GPH HP series pumps.

I'm leaning towards one of the 170GPH pumps. The 170 HP Series pump I believe is new, and it looks fantastic!!! Billet aluminium finish, preset shutoff at 7.5PSI, so no fuel reg is required. It also comes standard with -8 AN inlet and outlet fittings. Here's a pic of it:



And all the info can be found here: Holley Link - 170 HP Series

The standard 170GPH pump, comes with -10 AN inlet, and -8 AN outlet, the pressure is higher at 8PSI, and apparently it requires a reg.

Here's the info for that one: Holley Link - Standard 170 Pump

Can someone please remind me is -8 or -10 equivalent to 1/2 inch ????

[LXCHEV]

So at the moment, my choice is between those 2 pumps listed above. I'll have to price them both up and see if the HP series one is much more.

What are people's thoughts on the fact that one of them requires a reg, yet the other one doesn't??? Is one better than the other, or any more reliable etc... ???

Just to add some more interesting info to this thread, here is another pump that LX406 has mentioned on another forum...



They are from Quick Fuel in USA. US$288 from summit plus around US$50 postage and handling.

Details:
Mechanical fuel pumps for high-horsepower engines.
These Quick Fuel mechanical piston fuel pumps flow an amazing 204 gph. They will operate at a consistent 4 to 50 psi using an aftermarket regulator.

Other features include:

* Compatible with gasoline and alcohol
* Zero drop in fuel pressure throughout the entire rpm operating range
* Variable displacement design easily can accommodate up to 2,000 hp
* No diaphragms, valves, or gaskets
* Maintain fuel pressure with engine shut off
* Hard coated 6061-T6 billet aluminum
* Stainless steel internal components
* 25 lbs. pushrod force
* Available for carbureted and fuel injected applications
* 60 psi unregulated for carbureted applications
* 70 psi unregulated for fuel injected applications
* Weigh only 1.1 lbs.
* Fuel pressure regulator required, sold separately
http://store.summitr....5&autoview=sku

It sounds like a pretty hard-core pump. The fact it will support 2,000 HP makes it sound like overkill for my engine... but it's very interesting, and really, not even that expensive considering!!!!