[Zombi]

I'm working on putting fuel injection on my other car (a ford), and I came across this while looking at surge tanks. I'm curious what you guys think about how the material will stand up to gasoline and impacts from road debris over time.

http://www.geocities.com/hrayhouston/antisurgetank.html

[TheMonkey]

i think that captures the spirit of hot rodding. very creative.

i would be cautious though. when it comes to high pressure gasoline, my preference is leaning toward a manufactured system, although he has obviously had it work well for him.

a concern that comes to mind is heat, and can that tank withstand it? some higher horsepower combos with high temps around the fuel lines that all get returned with high capacity pumps can cause problems. you have read about the problems that people have had on hot highway long stretches? i wonder if that surge tank would not handle the heat before the pump starts cavitating? i'd rather pull over because the motor has no fuel instead of because the car is on fire?

looks like he was on a few HR Power Tours, so he probably passed a lot of those guys that were on the side of the road waiting for their fuel to cool, but maybe his combo just does not generate a lot of heat?

just thinking out loud, sharing a concern, but like i said.... very creative.

[HWYSTR455]

I agree, creative, though I think I would want something that's metal. Heat would be a concern, as well as gas or additives eating away at the plastic over time. Also, since the capacity isn't that great, wonder just how much it helps. When not under load, there's a good bit of circulation of fuel, and it would seem to me that since it's not being fed by, for example, the return line as well as the feed, it would run dry pretty quick if the main feed line doesn't supply. Like around a cloverleaf coming off the highway or something similar. Surge tanks need to be sized properly for the engine (or demand) they are intended for. (Most import performance applications use a 1 or 2 liter capacity, to give you an idea.) If the tank is designed well, you can use a smaller surge, since there's less of a chance of aireation. (Darn I struggled with spelling that!)

If your running a performance engine in a preformance application, then designing (and cost there of) a supporting fuel system is part of the overall project, and can't be overlooked. I had a stainless tank done for two of my cars by Rock Valley, both with internal baffeling and one with a built in surge tank. I think I paid 720 for the one, and 875 for the other. Both had integrated pump & filter mounting brackets. Search the forum, I posted the build diagrams & pics for these tanks...

There are also add-ons that you can use placed inside the tank to avoid using a non-factory tank. The pic is a Fuel Safe surge/collector, and if you add a few baffels in a factory tank while using this, you can use a lower capacity surge tank. If you go this route, buy a new tank, for a number of reasons. Most won't weld on an old tank, welds don't hold as well, and they'll leak.

[Skip Fix]

I always wondered if a surge tank BEFORE the pump after the tank would do the job. Kind of like a dry sump oil system. Coffee can sized slightly below the tank, feed near the bottom , bleed line off the top to get the air out, outlet dead on the bottom.

The whole object of the sump is to prevent the pump from sucking air in a turn or other G force manuvers. Carbs have the buffer of a fuel bowl injectors don't.

[HWYSTR455]

Exactly, sucking air, and sorry for my attempt at spelling! Anyway, the surge needs to be 'fed', and should be under pressure, so most use two pumps. To gravity feed the surge, it would have to be lower than the tank, and even if you use a check valve on the bleed, if there's a vacuum, it won't bleed the air off. Also, the pump would have to be lower than the surge, technically, and would probably drag the ground! Heh-heh! Good morning by the way Skip!

[Skip Fix]

I was thinking something like those aluminum radiator overflow cans would be easy to adapt.

I wonder about a small one up front near the motor, then it could be pressurized.

[HWYSTR455]

There's so cheap, and everyone makes one, not worth really fabricating one IMO. Here's a simple link from SDS about surge tanks:

http://www.sdsefi.com/techsurge.htm

eGay has a ton of tanks reasonably priced, and 75-100 bucks should get you a decent one:

http://search.ebay.com/surge-tanks_W...sooZ2QQfsopZ32

And again, if the tank is done right, you don't need one really. Putting one up by the front would mean another return would have to be run, and it could also get hot.

[Tom Vaught]

Marty Palbykin had a surge tank on his daughter's Grand Prix with the SDS system and it worked well.

He fed the system with a normal Pontiac type engine mounted fuel pump and used a gravity return type set-up to the tank. A spill over tube maintained the level in the surge tank. It was the inlet point for the return line.

The efi pump was next to the surge tank and always had liquid fuel to it. There wasn't much heat to get to the efi pump as the surge tank was constantly circulating fuel back to the fuel tank anytime the engine was running. Very little tear up of the stock fuel system.

The efi system from SDS worked surprisingly well for it being an early generation system. Marty took me for a ride in the car a few times.

SDS said that you could use mild steel for the surge tank or aluminum but I would probably worry about some rust unless the tank were chromed or galvanized after fabrication. Stainless or aluminum for me.

Tom V.

[Zombi]

Thanks for all the info. The goal for this project is to build my 69 Mustang into a nice daily driver with an EFI 5.0 and AOD, for under $3000. I'm hoping to (someday) end up around 350 horsepower so the fuel system needs to be able to able to keep up. Yeah it's a Ford, but if it matters we can pretend it's for my Firebird.

What I like about the setup in the link is that I can use the stock in-tank fuel pump off the donor car for the project (89 Mustang). It's a very common part and I should be able to quickly find one if the need arises. Plus, I already have one which saves some money.

Monkey: I had not really considered the heat aspect of polyethylene. According a quick search, it melts at around 250 degrees F. Due to the low pressure pump continuously circulating fuel through the surge tank, I doubt the fuel inside the tank will ever get that hot but that temp still seems a bit low for me to feel comfortable. Especially since I'd like the option of mounting the surge tank in the engine compartment.

HWYSTR455: You raise a valid point about the surge tank sizing. In the system I am thinking about, the fuel return line would be run through the surge tank and then back to the fuel tank. This should help keep a smallish surge tank from going dry while the the main tank pickup is uncovered. Do you think the surge tank capacity is OK if it is on par with the capacity of a carburetor's float bowls?

The fuel tanks you have are bada$$ and I would love to go that route but the cost is an issue. What is involved in installing the Fuel Safe in-tank surge tank in a stock replacement tank?

And for those people who end up reading this thread as the result of a search, here is a link to HWYSTR455's tank information: http://forums.maxperformanceinc.com/...=458402&page=2

Skip: I was thinking about the aluminum radiator overflow cans also. i think if I could find one that allowed me to put the EFI pump inside it, that would be optimal. I'll keep looking at them.

Tom: I had not considered using a mechanical pump on the low pressure side and I think it's a great idea. The cost would be less and I wouldn't have to listen to it. I'll look into it further.


Here's a different setup I found that uses a remote oil filter mount:
http://bcbroncos.com/store/product_i...roducts_id=119

Some people are using it:
http://www.midnightdsigns.com/james/FuelSystem.htm (This guy has a nice site)
http://classicbroncos.com/efi.shtml

The good side is that I could build something like this for around $40 (including the filter), it would be very easy to change the fuel filter, and it would also filter the fuel to 10 microns. The bad is that I'm back to having to buy an external high pressure pump. Now if I could only mount the pump inside the filter...

Thanks again for your excellent input and ideas.

[HWYSTR455]

Zombie - You know, I'm almost certain a number of people make tanks for your car, but could be wrong. I know Fuel Safe does, but they're expensive (and the best).

http://fuelsafe.com/pdf/Mustang.pdf

Shop around, I think you might be surprised at the cost, pretty sure the price has dropped over the last couple years.

You also have a point about the float bowl comparison, so I guess I was off on that comment. I just assumed there had to be different sizes for different demands, but after further thought, I'm not as sure about that line of thinking. My line of thought I believe was due to the fact that I never accounted for a 'deadhead' style rail setup.

Tom - The GP your talking about, that was a deadhead style rail setup, correct? I can see how that kind of a setup would work in that case, and also see how the fuel in the surge tank wouldn't get that hot due to constant circulation.

Ok, I went back the SDS link and looked at the diagram, and it isn't a deadhead style rail setup. Hm, twice today I've learned something new!

As for installing one of those surge tanks in a factory tank, like the pic I posted, it's simply a matter of cutting a hole in the top of the tank, dropping it in, and running a feed & return line to bulkhead fittings. You could probably do it for about 600 bucks max. Another option would be to use one of the Rock Valley or other people's 'Tuned Port' drop in units, like the pic I attached here:

This uses a factory style in tank pump, which allows for limited growth though, so keep that in mind...

[Karch]

I think Krisr is using a small cell fed by a low press., hi vol pump, and out to a high pressure pump.

[krisr]

Nah, my cell has a 2L sump built into it and my feed & return lines go into the sump, so it's essentially never 'dry', for that you'll need an adjustable FPR.

You can run a surge tank anywhere really - in the trunk, underneath the vehicle, aslong as your fuel return line goes back to the surge tank, you'll be fine. My friend had his 260Z datsun hooked up so the return goes back into the main tank, not the surge tank, on the dyno it sucked a 1.5L surge tank dry in about 10 seconds turning 570rwhp. Lucky we fixed it as it started to have leanout issues on the track.

[Zombi]

Well, I've finally gotten around to finalizing the surge tank for my EFI (ford) project...

Here's what I ended up doing:



The fuel comes in on the right side from the lift pump. The rear fitting on the left side is the feed for the high pressure pump. The tee fitting has the return from the engine coming in on the left and the return to the tank going out the top.

It's mounted on a bracket that also holds the lift pump, a Carter P4070. Here's a work-in-progress pic of the setup:



There were a couple of options for the fuel filter:



The project still isn't finished yet so I can't say how well it works. Look for an update in another five months.

I made a page on the subject, it also documents some of my other not-so-great attempts...

http://carmutations.com/tiki-index.p...FI+Surge+Tanks

[Karch]

Make sure you don't lose pressure at the top of high gear under high load, high rpm.

Also, the return T is a restriction to flow itself, so you might have pressure fluctuations when fuel demand is low.

Just a couple of thoughts.

[TheMonkey]

looks nice. i know there is a megasquirt guy running pretty much the same arrangement for a couple years, works great. kind of a pain to change the fuel filter though...

[6D6GOAT]

nice thread..i too hate having to keep a half a tank of gas in my car so i dont lose fuel pressure when i get on it.

should a static electricity charge build up be a concern if you use a plastic one?

[Zombi]

Karch: those are good points. Another tee with a return line on the inlet side of the assembly would probably cure any low-demand fluctuations. We'll see how it works out once I get the rest of the conversion finished. I'm installing a digital fuel pressure gauge so I'll be able to keep an eye on it.

Monkey: This kind of setup is actually pretty common in the Ford EFI world also. I think the hardest part about changing the spin-on filter will be sacrificing over a quart of dirty gasoline.

Vic: I'm not sure about the static electricity build up in the plastic water filter setup. I ruled out the plastic tank due to too many unknowns like that. Will it withstand enough heat? Will the gasoline eat the plastic? Will it take a few knocks from road debris? Will it cause me to die a fiery death? The last one was especially important to know for certain.

[6D6GOAT]

i have decided to run a surge tank setup with the remote oil filter setup. i have a question. if i run a high volume/low pressure electric fuel pump to the surge tank does the pressure have to be regulated in any way? or just plug and play.

im stoked...i was getting real tired of getting on it only to have a big bog and notice my fuel pressure drop 20 pounds because the pickup in the tank sucked up some air

[6D6GOAT]

well, i scetched out what im planing to make for a surge tank. i would like some input from you guys. on another board it was brought to my attention that the hotter fuel returning to the surge tank from the fuel rails will cause the fuel to heat up because it was simply recirculating the fuel causing the fuel in the surge tank to get hotter and hotter. i see that some have ran a "T" fitting but i was concerned that there would be trouble purging air from the system as the fuel returning from the fuel rails and the escaping air would be crossing paths in the same line.

so i came up with this idea. all the air and excess fuel will exit the same direction up and out of the return line on top of the surge tank. the positive pressure of the low pressure/high volume pump under the divider plate will keep the fuel returning from the rails up and out the return line to the tank as well as easily purging any air from the system. any thoughts?

http://img.photobucket.com/albums/v3...rgediagram.jpg

[TheMonkey]

the instances that i have heard/read about overheating the fuel was the entire system, where you could not even put the palm of your hand on the gas tank by the time the pump cavitates. typically after a few hours of driving at cruise speeds on a hot day. i'm convinced that it is from oversized fuel pumps that recycle the fuel too much through the fuel rails and engine compartment lines that act like a heat radiator. the velocity of the fuel is so much faster too with the real big pumps. so, take a look at your power requirements and make sure you are sized right. so many people just put in a massive pump figuring that bigger is better. if you are making loads of power on a car that can cruise too (sig says supercharged ), maybe a variable type of pump (some people have adjusted voltage to the pump depending on dynamic fuel needs). also, if you have the space, maybe an in-line fuel cooler http://store.summitracing.com/partde...5&autoview=sku

from your drawings, i'm not sure that a divider plate is necessary, as long as you have the benefit of gravity. for sure, i think a T fitting on the return line would be better than returning the entire line through the tank. if your low pressure pump feeding the surge tank is of adequate size, and the return line from the T fitting back to tank is sufficiently sized, the direction of fuel flow will be from surge tank to return T and back to tank, rather than fuel flowing back to surge tank from the return T so that any fuel that was heated up in the fuel rails will get returned back to the tank rather than into the surge tank first.

if you return fuel directly to surge tank and recycle it again up front, hard to imagine it wouldn't get hotter and hotter. so, my suggestion would be to use the T fitting and make sure your low-pressure pump is pumping enough relative to your hi-pressure pump to keep the flow of fuel going OUT to the return rather than back IN from the return.

i have decided to go the www.tanksinc.com route, but fooled around with a similar idea as yours. i was going to use this small fuel cell, and drop a walbro in-tank pump into it. an in-tank pump should help keep the fuel cooler, as the pump will be cooler. http://store.summitracing.com/partde...5&autoview=sku