Hi everyone.

I'll be installing a Magna Charger MP 122 on my car this winter (in progress) - and I'm trying to put together a fuel system to support it that will be more than adequate but won't break the bank. Here's all it says in the blower install instructions:

"The required modifications to your engine and fuel delivery system are dependent on the boost pressure and power output. Aftermarket pistons, connecting rods, and valves are recommended to assure engine durability. See “Boost and Ignition Timing” on the next page for further information. The higher power output will require an aftermarket high-volume fuel pump such as Edelbrock #1711 (130 gal/hr), 1721 (110 gal/hr), 17000 (175 gal/hr), 1791 (120 gal/hr, electric), or 1792 (160 gal/hr, electric)."

I plan to run around 6 pounds of boost. Hopefully around 550 HP. Here's what I've put together so far, but I may need more - or less....that's why I'm posting:

350-1711 Victor Series Racing Fuel Pump SB-Chevy
350-8192 Single Regulator, Dual Outlet, Standard Flange

This car was originally a carbed car and will remain so. There are 3 hoses that go to the fuel pump presently (stock) one for fuel inlet, the second for fuel out, the third is a smaller hose for return to tank (I think). I'm hoping to run a higher volume mechanical pump if possible. Trying to stay away from electric fuel pumps and FMU's if possible.

-Will the stock supply hose be big enough?
-Should I get a regulator with a fuel return fitting? Which one?
-Am I better off using rubber hose from the tank to the pump, or should I go with braided line?

 

I found that the long draw from the tank is what limits things, usually. Any 110-120 GPH mechanical pump can keep up at the 500-550HP level but it usually can't handle the long draw without some help, especially in the low gears where it's fighting the g-forces of hard acceleration. All fuel pumps do a better job pushing than pulling. I've done plenty of 11 second nitrous setups using a low pressure electric "helper" pump back by the tank plus the block-mounted high volume mechanicial pump through the stock 3/8" lines. My current go-to "helper" pump is the Holley Red mounted back near the tank. No regulator required since neither pump is trying to outrun the other.

I also run this setup on my roots-blown Malibu although it's only making 470HP at the crank/390 at the rear wheels right now.

 

Whattaya mean "it's ONLY making"?!?!

Low flow from the tank to the pump was exactly one of my concerns too Damon! I'll assume I only have 3/8" stock diameter hose from my tank also...So - just a high volume pump alone won't pull it through fast enough?

Not saying a booster pump isn't a bad idea at all, but if I don't want to run a separate electric pump, what are my options then? -Sump the tank for 1/2" diameter hose? -Install a hi volume 3/8ths in/out electric pump close to the tank and ditch the mechanical pump all together?

-How reliable are those "Red" pumps?

 

The Red pump is very reliable. The first one I ever installed in my buddy's 72 Chevelle is goign on 4 years of weekend fun duty without any problems.

You might be able to get by without a "helper" pump, you might not. I first ran into the problem in both my Malibus (previous 79 and current 78) running as slow as high 13s using a high volumne block-mounted pump only and stock lines. I then went through the process of removing the "sock" on the tank pickup thinking it was the problem- no dice. Then I hand-bent fresh 3/8" line with very smooth bends all the way from the tank to the pump- still no dice. I was kinda shocked that it outran the fuel lines at such a modest power level. I've probably "fixed" the fuel system on a half a dozen cars now using this same type of setup.

 

Not too sure what you want to spend but I will post what I have. Not expecting you to copy this setup as it is kinda strange, but I am paranoid about running out of fuel so... here it is. Oh and it has run for a year so far without ever dropping a single PSI. And it is going to feed my 200 shot of N20 at the same time. Should still not drop a bit.

Tank: 15 gallon summit fuel cell, baffled, foamed and all. $215

http://store.summitracing.com/partde...5&autoview=sku

Pre-pump filters: 2 Fram canister filters, Nice cheap and easy to service. $41

http://store.summitracing.com/partde...5&autoview=sku

Pump: Holley Volumax pump. Gearator style pump, pretty quiet and re-buildable. This link is to a very similar pump. Mine pushes 160 GPH, this is a 150 GPH unit. Same pump, new name pretty much. $210

http://store.summitracing.com/partde...5&autoview=sku

Post pump filter: Holley log style fine filter. Easy to install any place. This is not the filter I have, I can't find mine, but it is like this. Cost me about $120, looks like they are cheaper now.

http://store.summitracing.com/partde...5&autoview=sku

Hose: Twist tite hose. Easy to assemble and cut. Holds up VERY well and is cheap. I went with 8-AN feed and return to pump with 8-AN feeds to the carb too. $30 x (How ever much you need)

http://store.summitracing.com/partde...5&autoview=sku

Fittings: Twist tite hose ends. These might look mundane, but there is absolutly no way to pull these out of the hose once they are in. You have to cut the hose off the barbs. All around $4, some are like $8 for 180* turns.

http://store.summitracing.com/partde...5&autoview=sku

And thats it...haha.

I turst my fuel system so much that I won't even think twice about adding a SC to it. Its a nice feeling to have knowing you are just NOT going to run lean. I plan on adding more power to my car later and I know know that it will handle it just fine.

Hope this helps even a little. Later.

-Dennis

 

Thx for the ideas Damon and Dennis....

But what about my stock fuel pump return line? Just plug it? Or is it better to use it if I can, and get a regulator with a return fitting?

I realize that I've got this "thing" about electric fuel pumps....I simply hate 'em...they've stranded me in the middle of nowhere more than once. That's why I asked about how reliable the Holley "Red" pumps are...Never had a mechanical pump do that to me, so if I can run one, I will!

Certainly, you have the cheapest way to go about it Damon. But I take it you're using a mechanical fuel pump that doesn't require a regulator? Those seem to be limited to 110 GPH or less, and I'm not sure if it'll feed a 400 sb OK or not.

Dennis - Def. not the cheapest setup, but I don't doubt it'll feed most anything!!
But I think I'd rather just drop the stock tank and install a sump rather than run a fuel cell. The twist tite hose seems like a good idea from the tank to pump, then I can run braided line to the carb from there.

Money really isn't the object here, but ease of install and reliability is. I've found out over the years that just because something costs alot doesn't make it good or reliable. Sometimes you can get away much cheaper and have the same result or better than the expensive stuff.

BTW...all the suggestions help!! Please keep 'em coming!!

 

Well I see that you do have a thing against electric pumps. They really are not bad at all. Just wire them perfectly right and all will go as planned. I use an eromotive return style regulator. It is a nice piece. I return back to the tank using 8-AN line too. Def do a return line. It keeps the fuel flowing and that keeps it cool. You don't want warm fuel sitting near your S/C and then getting shot in. Plus if you end up using an electric pump, the return style will let the pump live for much longer by letting it pump all the time freely. If you only have a feed, the pump gets choked up and can't spin and has to wait for the carb to use the gas. This puts a lot of stress on the internals of the pump. (electric motor). Imagine holding a fan while it is on for a LONG time, it won't like that at all.

Get any electric pump. WIRE IT WITH A PAINLESS KIT. That will make it run like magic. And use a return style reglator.

I have many pics in my CD site. Plus i can take more if you need to see what mine looks like.

Lemme know. Later

-Dennis

 

Thanks again Dennis.

Guess I'll have to get over my electric pump worries....I think my plan will include the Holley Volumax fuel pump you listed above:
http://store.summitracing.com/partde...5&autoview=sku

Trying to get away without sumping my stock tank or adding a fuel cell if I can. I'm hoping -6 AN lines will provide enough.

I noticed right away that it has 3/8ths inlet/oulet connections, which I think will adapt nicely to the stock lines. I'll mount it in the rear close to the fuel tank so it doesn't have to pull the fuel out that far. Since it's already rated at 150 GPH, I think it'll be able to supply enough for my future setup. I'll then add a in-line fuel filter, then a regulator....

I am however, a little iffy on what type of regulator to use. Most of the ones I've seen come with a bracket that mounts to the carb base and has a inlet on the bottom and two outlets - one on each side that goes to each bowl on the carb., plus a 1/8th inch pressure gage hole. Having a hard time figuring out which one has a fuel return port. I'd like to hook my 5/16ths return line to it instead of plugging it. Which one should I get?

3/8ths is roughly a -6 AN size right?

 

Yes, those 2 sizes are exactly the same. Each AN # = 1/16" so 6x(1/16)=3/8.


With that outta the way, you are on the right track with mounting it as close to the rear as possible. What is your main concern for not wanting to sump? Cost of sumping? It will help a lot and make the pump not have to pull at all. My cell has 2 outlets that use gravity to feed the pump. For example, if my pump was off and "open" so that the gearator drive was outta the way, fuel would just pour out from my tank, past my pump and out on the floor. This means that gravity is feeding my pump, it doesn't have to pull at all. All it has to do is push push push. Pumps love pushing and hate pulling. A sump lets that happen, not to mention helps cornering fuel starcation too.

Here is the link for the Reg that I have. You can use it for FI or carb. You can run a return or not. Best, most versatile reg around. I love it.
Here it is:

http://store.summitracing.com/partde...5&autoview=sku

Can't go wrong with that. Has 3/8 ports like you want too

 

Nah, it's not the cost so much really. The gas tank is pretty much the only thing I have never removed from the car, so I guarantee the bolts and straps are artifacts. And I'll probably end up busting a line or something. -But it makes sense to sump it.....

So.......I've decided to give it a go! But even though I have a MIG welder, I think I'll give the tank to a pro and let them weld it without blowing themselves up. I assume you'd have to pump in an inert gas while welding, but just guessing. But it helps me figure out how the system will end up now.

After getting the tank sump added:
http://www.jegs.com/webapp/wcs/store...10002_77096_-1

I'll get a 1/2 inch to 3/8ths adapter from the sump to the 150 GPH fuel pump, then 3/8hs to -6 AN barbed adapter to supply hose up to the regulator, two braided regulator outlet hoses to each carb bowl, and a barbed fitting return hose (1/2 inch or -8 AN size) back to the sump. I'm sure I'm missing a few elbows and such, but you get the idea. Oh, and a "Painless wiring kit" for the pump.

Sound like enough to feed it??

 

Yeah, you are getting there for sure now. Can pumps return back into a sump? Mine pours into the top of my cell. Research that... Apprt from that, you sound pretty good to go. DRAW IT OUT. only way to really make sure you are getting all the fittings you need. I also when under my car and took a tape measure and traced the place where I wanted it all to go so I knew I was buying enough hose.

 

I guess I need to understand the question 1st....I can't seem to find any pumps with a return port on them....just one "in" and one "out" port. I figured the fuel would return via a "bypass" regulator to the other -8 sump connection right?

I guess, ideally you want your fuel return to go to the top of the tank to prevent "short circuiting" but since I'm retaining my stock tank, it doesn't have a big return fitting on top of the tank like a fuel cell would. So I'm kinda stuck there so far as I can see unless I just tap my regulator fuel return into my 5/16ths inch stock fuel return line...it goes to the top of the tank.

BTW, I looked at your CD - Nice ride! I can see you've put alot of work into it.

 

Thanks for checking it out.

You are on the right track with wondering about returning to the top of the tank. i would if I was you. Seems like the right thing to do. My pump actually has a return port on it, but it is not used to return fuel from the carb to it, the pump itself needs to return to the tank. I have two things returning to the tank. The pump and the reg. It is kinda funky looking system, but thats what the instructions said I should do, so I did it. Works like a charm and fuel stays nice and cool. If you put your head agains the cell you can hear it pouring in. haha.

 

so dennis, what do ppl think when they see you popping the hatch and then pouring fuel into the trunk? haha.

 

I get all kinds of looks and gas attendants coming out to see what I am doing.

Random people on the side walk stop and wonder. haha.

Last time a little old lady came by and said "wow, I didn't know cars came like that!" haha. So I explained a little.

ALL kinds of stuff happens. its funny. Makes spending all that $ on gas a little bit of a better time.

 

haha. i hear ya. if you're gonna spend 50 bucks at the filling station, might as well have a show too!

 

Haha, true. The car acctually has OK, milage for the cam that it has, but I am getting a smaller cam and a dual plane installed in a week or so, so that should help. Anyways, that is neither here nor there. haha.




Confuzed1: I don't think that there are pumps that return to the pump. I have only seen the kind like mine that have the pump return to the tank.

It is cuz the pump actually pumps too much fuel and to regulate itself, it pumps the extra fuel back to the tank. Thats what I understood at least.

 

Dennis -
Naw, I meant from the pump to sump. Your pump must be internally regulated to some pressure then.....right?

A return or "bypass" regulator should do the same I'd think. (If I used a non-regulated pump).

You never know, but I may just start out with a fuel system like Damon recommended, at least to see how well it works on my setup.

He did say one thing I like to hear!
Dennis - I wouldn't hesitate running a SC with your fuel setup as well as nitrous!! I think it'll handle most any engine upgades IMO.

But the car I have will not see any further engine "upgrades" after this blower install. I'm an old guy, and I realized long ago that "no matter how fast you think you are - there's someone faster". ha ha!

So Damon - I'll try your setup to see how well it'll work.

On other notes, my 408 is apart, and everything looks sweet! Just normal wear on the rod bearings (they were barely broke in) but I'm replacing them anyway. -Trying to do a piston change to forged and put it back together with a new cam. Engine was checked by the local machine shop less than 5K ago and I had the cylinders honed for new rings so I "shouldn't" need any more overboring. I can see the crosshatches still in the cylinder bores!

Thx again for the help.