HS Professor, where did the advice for -12 come from, Aeromotive? If not, I would be skeptical about that.
It is apparent that a few folks tend to way overthink and "over-engineer" their alky fuel systems.
I believe you will find many different approaches that will all work just fine, unless your build is meant to chase some kind of ET record. I suggest you pick a moderate one, (preferably one of the more simple options, for lower expense and ease of installation / fabrication). Try it. If it works, great, you saved time, money, and work. If not, you have a bunch of guys here ready to help you troubleshoot it.
One piece of advice I absolutely believe you should consider, is providing for a return line equal in size to your feed line. If you think about it, there will definitely be times when you will need your system to bypass 100% of the fuel it is supplying to your fuel log. And if it can't, (especially with a belt driven pump at high RPM), that is a huge spike in pressure and fuel volume that will need to find some place to go. (Most likely pushing a bunch past your needles/seats, out the bowl vents, and into your intake).

Thanks for the replies !!

I've done some poking around and come to find out three local guys we race with, with very,very good cars run the same Aeromotive pump with -12 line feeding the pump !! I've come to believe the Aeromotive pump moves a lot more fuel than a properly sized BLP. All three also run -10 returns, but I figure they're probably just using the old feed line as a return.

And yes, Brett from Aeromotive went into great detail on why using -12 to and from is important, I just didn't want to believe it

quote:

People normally take the easy road.

Trust me, that's not the case

So, after the expert tells you what is needed, you ask DRR for opinions?

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So, after the expert tells you what is needed, you ask DRR for opinions?

Yup, I ain't stupid ……. The directions say, use a -10 feed and return. The "first" expert from Aeromotive said a -10 with a rear cell should work but is not recommended, then I get passed along to "second" expert on a totally different question and he says I NEED a -12 feed and return and a different regulator than expert #1 recommended. See the pattern

So, I post here and get actual racers tell me what works for them, then dig a little deeper and find 3 friends with good solid information and real world proof of what works with nearly identical set-ups. While I still find it hard to believe I need -12 for a mid 9 second bracket car, -12 it is !!!

Thanks for your wise azz comment

I have fought fuel problems and that is one area where I will not cut corners. Larger hose is not that much more on fittings or hose so I say if you are buying new hose why not get the larger?

Also if you are using a belt drive pump up front I would try to find small tank for up front then maybe an electric pump to keep it full.

Well i don't think you NEED -12 but try it. It probably will be fine. Just try to get that cell as high as possible and hopefully you have a low mount for your pump. Belt pumps aren't really designed to pull fuel so these little things make a difference. My s10 runs 5.50 on alcohol without a hesitation with -10 line. IDK what that equates to in 1/4 mile but i know its faster than than mid 9's. I also find it hard to believe that an aeromotive pumps so much more fuel that it needs larger lines. I CAN tell you that bolaws sizes his pumps to your HP and mine is good to around 900hp. More than that and they recommend the next size pump.

if over engineering means a one time install with no issues(hopefully lol)then thats a good thing.i personally have tried lots of routes getting to an end and found what has worked for me and others.there are still many ways to do the same thing that may work.i do strongly agree with the size of the line and g-force,therefore front cell and big lines .good luck

I had fuel cell in trunk with belt driven enderle pump. Long car, 64 tempest. I ran-12 to pump and-10 return. I had to install supply line check valve in rear of car. Carbureted engine.

You MAY not need -12, you MAY even be able to get away with -8 or even -6 but why chance it? Too small will have problems, too big no problems also you MAY be able to make rear cell work with belt drive but you MAY have problems.

Rear cell works really good with electric pump mounted behind and below tank. Not so good the further forward and up the pump is mounted. That is why every single belt drive mechanical pump recommends you mount tank up in front to help gravity and G-Forces feed the inlet.

If you want to put a mechanical pump up front with rear cell you are already making it hard to work good, then put too small of a hose increasing how hard pump has to draw the fuel could be asking for trouble. May work some have done it and it worked. Others have not and then had to spend good money on top of bad money to fix it plus all the track time to figure out what the problem is.

Sounds like both recommended -12, but differed on regulator.

The reason bolaws suggests -10 instead of -12 is the weight/volume of fuel in the line is affected by the g forces. Its not because your choking the pump. I know everything we do we think bigger has got to be better but it may not be the case in this example.
All this talk got me thinking. I've been running the same pump for 17 years. Sent it back a couple times for a freshen up and updates but maybe its time to replace it just because its been a very long time

K I S keep it simple

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Originally posted by xtended_s10:
The reason bolaws suggests -10 instead of -12 is the weight/volume of fuel in the line is affected by the g forces. Its not because your choking the pump. I know everything we do we think bigger has got to be better but it may not be the case in this example.
All this talk got me thinking. I've been running the same pump for 17 years. Sent it back a couple times for a freshen up and updates but maybe its time to replace it just because its been a very long time

The G-force on the fuel volume seems to be at first, a valid concern. When you figure out the actual force on the volume of fuel in the line, it is miniscule - like 0.2 lbf in the -12 line and 0.14 lbf in the -10 line. This results in a momentary pressure drop of about 0.45psi in either line. If the head pressure of the fuel tank isn't enough to overcome this, then work needs to be done. The car in my avatar uses -12 feed and -10 return with zero issues.

Rick!, Are you talking about your dragster? The tank is in front of the pump. Not 8 or more feet behind the pump.

Get some good made in USA hose, I know of a car had some junk chinese black braided hose was getting sucked shut, chasing their tails for months.

All this cheap chinese garbage,the chinks are probably laughing their azz's off at American's chasing their tails, trying to use the garbage burning fuel for nothing.

I agree with the chinese junk. I hope this current debacle has opened some eyes for companies relying on them for everything. They can't be trusted.

While I agree with placing a rear/trunk mounted fuel cell higher than the pump, you need to consider any potential negative effects, such as will the car ever sit on a forward-sloped surface. Ever raced at Bandimere Speedway in Denver? (Starts off heading downhill, finishes going uphill, and not just a slight angle).
Personal experience - My cell is a tall Jaz aluminum 3 gallon vertical model, (about 8" square x 16" tall). I run a BG400 electric pump mounted to the frame rail beneath the trunk, directly below the cell. Raced it that way at Bandimere for 2 full seasons without any issues, until one race I was down near the head of the lanes, (where the slope is at it's steepest angle), and a bad oil down had us sitting for nearly an hour. When it came time to fire up, it was hydro-locked and would not turn over. Turned out gravity had somehow found a way to fill the #2 cylinder with fuel. Took me out of that race. After pulling plugs and blowing the fuel out, drove it back to the pits and changed both floats and the needle/seat assemblies just to be safe, but they were only 3-4 weeks old, I honestly think the weight of the fuel at that steep angle just caused it to seep past the N/S slowly, probably was doing it every time I was in the lanes, but that long wait was enough to make it a real problem. It actually had me considering the idea of adding a solenoid actuated fuel shutoff in the feed line. I don't think a normal shaped, lower-profile or low-mounted fuel cell would have had the problem, which is probably what all the other door cars had that day.