240Z Baffled tank without a fuel sump

[24OZ]

Guys,

 

i did quite a lot of searching on here on this topic and I am still not too wise about it.

 

I found a company that specialises in restoration of tanks and they are willing to insert baffles into my 240 tank. Please can you guys advise me how it should be done as I want to hear them tell me the same thing.

 

I have decided to not go for a fuel sump under the tank, for aesthetic and safety reason as well as higher insurance premiums. Would a baffled tank without a fuel sump work or am I being unrealistic? And do I have to have an in tank pump for this to work right?

 

Also, since I have changed the size of my fuel supply lines to 3/8" and the fuel return line to 5/16" I will also have them fit the same diameter of inlet and outlet pipes on the tank.

 

I would appreciate your experienced comments, I am hoping that all they need do is to cut the bottom of tank and weld in baffles and that's it.

 

Thank you.

[jkube]

I've done my '72 zcar with the sump in the bottom of the tank, and really like how it works.

 

I can run the car right out of fuel before noticing any starvation problems on corners.

 

I have also done a turbo install on a '76 280z using the stock tank. Apparently the tank already has baffles inside from the factory. We havent run the fuel level down as much on the 240z, but it hasnt shown any starvation yet.

 

So I would say that you shouldnt have problems with baffling the inside of the tank. Just make sure that the baffles are setup to contain the fuel around the pickup, and still allows fuel to run "Under" the baffles when the level gets low.

 

Jeff

[24OZ]

Thanks for your input Jeff, I don't suppose you have any pictures handy showing what you did exactly?

[ihatejoefitz]

Your insurance guy checks out your gas tank!?

 

For what it's worth, I run my EFI 240 with the stock tank.

[24OZ]

For what it's worth, I run my EFI 240 with the stock tank.

 

So did I when my 240 had EFI, but now its turbocharged and will be developing a lot more HP, the engine will be punished more when the pump experiences fuel starvation.

[24OZ]

Your insurance guy checks out your gas tank!?.

 

Well I have to declare all modifications, and he wont like a fuel sump from a safety point of view. It would mean a higher premium.

[Clifton]

I don't know why an insurance guy would ask what mods you did, does he do thios with all cutomers? Never heard of such a thing. I wouldn't tell him.

 

You can do a baffle and and intank fuel pump pretty easy. Walbro 255 pumps are around $100 and good for 5oo rwhp easy. You need a donor efi tank. Z31 and MKIII Supra ones work good. I used a MKIII tank. Zero fuel pick up problems even when running low and cornering as the retun is dumped into the baffle.

 

 

[fentin_fury]

Rather than baffle my new tank I used a surge tank - requires two pumps and some additional fittings - but should prove impossible to starve in the corners.

 

Q

[24OZ]

Fentin - that was an option i was looking at but prefer this as a neater install.

 

CLifton - that's great work, sadly well past my abilities, I can't even weld.

 

Does anyone know if baffles will be enough or would I need an in tank pump also??

 

I found a kit on the net that may be worth considering, let me know what you guys think.

 

http://www.thedetailzone.com/Tanks%20Fuel%20Pump%20Install.htm

 

 

http://www.tanksinc.com/index.cfm/page/ptype=product/product_id=84/category_id=61/home_id=61/mode=prod/prd84.htm

[Clifton]

That pump is almost twice what they can be had for. That kit looks good but the problem is, the Z tank sits against the bottom of the car. If you used that kit the fittings would keep it from sitting flat under there. That's why I lowered mine where the pump openeing is. If welding is out of the question I would run a surge tank with 2 pumps or a 75-76 tank. 240 tanks with efi are terrible in hard turns with less than 1/2 tank. There is just a seperator between left and right, fine for carbs but not for efi.

[Pop N Wood]

The easiest way to solve your problem is to weld a cigarette pack sized sump on the bottom of your tank that has 3 half inch holes feeding it. Then create a new fuel pick up that goes into the new sump through one of the holes. The new pickup can enter the tank where the stock one does using bulkhead type AN fittings. With the fuel sender out you will easily be able to see to get the new pick up into the new sump

 

That way there are no lines on the bottom of the tank. If you are worried about the small bump of a sump, then bolt a skid plate over it.

[GD71240z]

Here is a link to one of our local club members cardomain site. There are a few pictures of his fuel tank that he modified with a sump. He is also a member of Hybridz.

 

http://www.cardomain.com/ride/563982

[24OZ]

Clifton, that's what I realised must have been the case after seeing the way you did yours, I really like it.

 

Instead of paying big bucks for this kit, I may get the shop to install me an anti slosh tray like they have done and then as long as the pickup and the return is within the tray it should work. I can then use my new external pump also.

 

here is close up of the tray:

 

 

 

Thanks to all about your comments on surge tanks and fuel sumps, they are a nice option but prefer Cliftons route or the cheaper alternative of just getting an anti slosh tray like the one above put in there with the pick up and return feeds directed into the tray.