Surge Tank Locations

[ktm]

Believe me, I searched and searched. I found a company in Australia (what is it about Australia and cars - they have all the EMS companies and surge tank manufacturers) that produces a variety of tanks with different mounting options (bottom, top and side mounts).

 

The easy solution is to mount the tank in the engine bay. There is plenty of room on the passenger side and you can easily locate the EFI pump below the tank.

 

The problem comes from trying to mount the surge tank by the gas tank. I see a nice flat spot between the gas tank and the moustache bar where a top mounted tank could fit. However, I do not see a good place (mind you I was looking underneath the car without it being jacked up) for the EFI pump since it should be located beneath the outlet of the surge tank.

 

Aside from heat issues and the safety aspect, is there a reason not to mount the tank in the engine bay? Is there another good spot to locate the tank?

[24OZ]

Hi,

 

I have seen it mounted both in the engine bay, oil filter side of bay, (not hot exhaust side). The other place I have seen it mounted which I prefer, is at the rear, just behind the diff., See pic below of my fuel pump, thats where they normally mount them, using that that long bracket and the two taller ones. www.xiotis.com/pump.JPG

 

You can have the lift pump there and the surge tank above and the high pressure EFI pump running on its side. If need be a simple heat shield can be made if you think that the exhaust is too close.

 

I have actually seen a picture of my local club members car, and thats where he has his.. I have seen some people mount the surge tank in the trunk, but for safety reasons, I don't like having fuel in the car.

[Tony D]

I have cars with all three locations:

1) near stock EFI pump location on stock EFI Pump Bracket (240Z) with primer pump up near where EFI pump is on 2+2's (angled rear floor in front of A-Arms)

 

2) on right fender well, with booster pump on Stock EFI Bracket in back with EFI pump underneath.

 

3) On FRONT of Radiator Core Support (Aquarium Filter Surge Tank) with an IN-TANK pump inside the Surge Tank, and the booster pump in back on the stock 260Z Electric Pump Mounting Bracket.

 

Of the three locations I have tried, I prefer the front of the radiator with the in-tank pump and the Rear of the Car. The car I had mounted on the right fenderwell just made the area inside the engine bay too busy, and like you said: it's hot. Anything you can do in the engine bay, you can do in front of the radiator and it will remain cooler.

 

Crash integrity is of concern, but if you have a proper pump circuit with crash interrupt (get it from any Ford Product with EFI---I know Tempo/Topaz have them behind the carpet in the Left Rear of the Trunk, and Ranger Pickups are on the passenger's footwell tranny tunnel near the firewall under the carpet) they reset easily, and will kill any circuit instantly in case of Heavy-G impact or Rollover. As long as you kill the pumps, the system depressurizes through the return line quickly to prevent fuel spewage during crashes---if it spills at all.

[z-ya]

I used the fuel tank expansion tank. Then I made a metal shield to separate it form the passenger compartment. You need to add more fittings (I TIG welded additional 3/8" NPT bungs). It works great, and is very stealth.

[ktm]

I read about your expansion tank setup. Unfortunately it would require welding, a skill I do not possess at the moment (though I have always wanted to learn).

 

I have figured out my mounting location. I have a spare set of the vertical plates that go on either side of the differential. I will use on of those as a mounting bracket for a side-mount surge tank. I will then run the EFI pump where Tony mentioned and the low pressure pump near the stock location.

[thehelix112]

I put mine just in front of the fuel tank. I fit a fuel filter, Bosch 044, a Carter lift pump and a ~1/2 gal surge tank under there.

 

 

Snizen tight and a total bastard to do up that last nut..

 

Dave

[thehelix112]

Oh I missed that point, I am not sure why you need the EFI pump to be under the surge tank. Its the lift pumps job to keep the surge tank full and hence the EFI pump supplied with fuel, not gravity.

 

On my setup I have never seen any fluctuation in fuel pressure (which is set at 60psi base).

 

Dave

[24OZ]

Some people say that the EFI should be under the surge tank so that gravity feeds it and it doesnt have to suck. But I dont think it should make much difference here, its not a great distance and the main thing air isnt in the fuel at this stage.

 

What are all the parts bolted onto Dave, looks like a neat and compact install, nice use of good quality hoses too. I have the rear control arms off the car and the 2 end Longitudinal brackets (at the rear of the diff) are off too. Plan is to bolt the surge tank on one of the longitudinal brackets closest to the lines, then have the efi and lifter pump located on the bar that runs across. I think the job of attaching everything is way easier when you have those parts off the car.

 

What I have yet to work out though, is how to wire the two pumps up , how have most of you guys done it? Have you used relays at the back there?

[24OZ]

KTM I just purchased this tank, it is compact enough to fit on the longitudinal arm, he regularly makes them. I can post how good it is when it arrives.

 

http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&ih=017&sspagename=STRK%3AMEWA%3AIT&viewitem=&item=270098552260&rd=1&rd=1

[thehelix112]

Hey,

 

Thanks for the compliments. Everything is bolted to the floor (via rubber isolaters of course). I also have the power to the battery feeding in from above through the floor. The 044's terminals are on the top, whilst you can see the lift pump's in the pic I posted (not hooked up yet).

 

I relocated the battery to the boot (as it sat where my turbo now sits), and each pump has its own relay taking its feed directly from the battery. I seem to remember hearing/reading something about a pump's flow ability dropping of markedly with reduction in voltage and didn't wanna toast my engine because of a crappy wire.

 

Good luck,

 

Dave

[ktm]

24OZ, I found this supplier of surge tanks in Australia:

 

http://www.tweakit.net/shop/product_info.php?products_id=123

 

Very nice looking pieces.

 

I went to my local custom speed engineering/fabricating shop next to my office and talked to them about fabricating a tank for me. He suggested that I let him modify my gas tank, welding in baffles and changing the pick-ups to 3/8-in. supply and return with AN fittings. Cost? Around $300.

 

I've decided to go this route instead of the surge tank route. By the time you throw in the cost of the tank and shipping, plus the second pump, you are around $200.

 

I am going to use relays for my pump(s). I am going to order my relays, wires, and connectors from Waytek. The only issue I have now is what Bosch relay do I order?

 

I bought a used Holley Red pump for around $32 that I will no longer need. I'd be willing to let it go for around $25 plus shipping if interested.

[24OZ]

Sounds like a safer way to do it. Good Luck and let us know how it works out! Pictures of how they mounted the baffles would be awesome!

[BRAAP]

Believe me, I searched and searched. I found a company in Australia (what is it about Australia and cars - they have all the EMS companies and surge tank manufacturers) that produces a variety of tanks with different mounting options (bottom, top and side mounts).

....

 

 

 

 

I found the same EXACT thing within the last year while building up the F-prepared car! I was wanting a surge tank and found during that exhaustive research project, that AU is where all the surge tanks, cool EFI systems such as WOLF EMS, (bought a V500 for project Fuzzy…), and some pretty spectacular hybrid cars hail… (Note to self… If we ever move… place Australia at the top of the list…)

 

I planned, researched, and purchased my potential surge tank, but never did install it. I bought a CSR tranny overflow canister, CSR 851, with mounting bracket, (BEAUTIFUL piece of work, CNC aluminum at 4.875” tall, 3” dia, holds one pint, with a nice CNC mounting bracket,) to use as my surge tank on my MS EFI L-28 race car. It is a little pricey at just under $80, but its overall size was pert-neer perfect, maybe a little big, but definitely not too large. Finding a vessel to serve as a surge tank that isn’t overly tall is not easy, (I was trying to use currently available “catch cans” and most are quite tall).

 

Any how, this CSR unit comes filled with yellow fiber material which would work awesome as an anti-slosh device, though being as I was running AV gas, I didn’t want to chance incompatibility. I spent some 90+ minutes with a dental pick removing that material through a ¼” NPT hole!!!! I then placed a sample of that material in a can with the AV gas and let it set for over a month. The material helped up to AV gas just fine, (this little tid bit of knowledge would’ve saved me an hour and half of picking… ). After completely emptying the container of its filler material, I could see that some sort of sealant was used to seal up the canister during manufacturing. This meant that I probably should pressure test this vessel and also be sure the sealant was compatible with AV gas. I hooked up a Schrader valve to the canister, placed the canister in a 5 gallon bucket of water, (my safety device to help absorb the energy IF the canister wasn’t able to handle 125 PSI of air), and pressurized it to 125 PSI! It held just fine with no leaks. Next I filled the canister with AV gas and let it set for a month, right long side the anti slosh material in its can. After that month, the sealant looked just as it did from the beginning, but just to be sure, I pressure tested again with the same results, held 125 PSI with NO leaks.

 

Ok, so this unit would work fine as a surge tank with AV gas. I’ can’t guarantee that will work with auto fuel as auto fuel additives may or may not be compatible with the sealant used to seal this container, but I personally wouldn’t be afraid to try it on my car, and in-fact, I just may if I don’t build a custom fuel cel with an integral surge tank for project FUZZY.

 

 

 

 

http://store.summitracing.com/partdetail.asp?autofilter=1&part=CSI%2D851&N=700+400179

[ktm]

cool EFI systems such as WOLF EMS, (bought a V500 for project Fuzzy…) , and some pretty spectacular hybrid cars hail… (Note to self… If we ever move… place Australia at the top of the list…)

 

I just purchased one from Ron Tyler. I just need to show him da' money now.

[Tony D]

I used the fuel tank expansion tank. Then I made a metal shield to separate it form the passenger compartment. You need to add more fittings (I TIG welded additional 3/8" NPT bungs). It works great, and is very stealth.

 

Evil, Evil, Evil! I bow to your stealthiness, oh great one! I now have a new favorite way to do it! Muahahahaa!

 

Great idea. My tank vents through a JDM 'dump tube' in the filler neck!

 

BTW, the relationship of the main pump to the boost pump is pretty much irrelevant as long as the surge tank is constructed properly.

The whole key to the Surge Tank Concept is to have the pickup to the main pump continually flooded with fuel under slight pressure to keep the main pump primed. The #75 Steve Millen IMSA car (Cunningham Racing) has two surge tanks almost the entire height of the car and 4" in diameter! ALWAYS had flooded inlet even if a big pocket of air was sucked by any of the booster pumps.

 

Fuel out the bottom, air and excess fuel out the top. The further between the two, the better. Taller than wider is the desired aspect of the tank profile.

[Pop N Wood]

The whole key to the Surge Tank Concept is to have the pickup to the main pump continually flooded with fuel under slight pressure to keep the main pump primed. The #75 Steve Millen IMSA car (Cunningham Racing) has two surge tanks almost the entire height of the car and 4" in diameter! ALWAYS had flooded inlet even if a big pocket of air was sucked by any of the booster pumps.

 

Are you sure the surge tanks were that large to help with fuel delivery, or to get around some rule limiting fuel tank capacity?

 

Smokey Yunick mentioned that racing trick in one of his books. They had a rule limiting tank capacity, so he added enough fuel line to hold an extra 5 gallons of gas.

 

Isn't the expansion tank plastic? I hope your metal shield totally seals the tank from the passenger's compartment and includes a vent/drain to the exterior.

[z-ya]

In fuel injected road race applications, the surge tank is there to prevent fuel pump cavitation under hard cornering G forces. Like Tony said, the taller surge tank the better. This minimizes standing fuel waves in the tank. The wider the tank, the bigger the wave, which makes bigger troughs. The troughs will cause pump starvation.

 

I designed a fuel cell that sits in the spare tire well of a 240Z. It has a surge tank built in. It has been working great for 3 years of road racing. It is applicable to both EFI and carburated setups.

 

 

Yes, you must use a steel expansion tank (unless you are good at plastic welding ). Hear is a schematic for using the expansion tank as a surge tank.