Fuel Tank Drop down clearance

[positron]

Has anyone removed the fuel tank on a Brammo A2? Other than the PITA coolant lines I'm concerned about the upper corners clearing the frame supports. It doesn't look like a straight down drop.

I seem to remember the Brit's having a lot of issues but don't remember of any not being done by the factory.

[Terry Kennedy]

Has anyone removed the fuel tank on a Brammo A2? Other than the PITA coolant lines I'm concerned about the upper corners clearing the frame supports. It doesn't look like a straight down drop.

Unless you really need to remove the tank for some reason, I'd suggest drilling out the rivets holding the rear firewall to the frame (behind the seats). That'll get you good access to the top of the tank (you can easily pull the fuel pump, for example). Then just re-install the firewall w/ rivnuts, allen head stainless screws, and the rubber/metal washers (part numbers available on request if you need 'em).

I seem to remember the Brit's having a lot of issues but don't remember of any not being done by the factory.

Did you see CalScot's "all hands on" fuel tank party at AtomFest I? CalScot, the Hallett folks, and most of the UK factory folks were involved.

[positron]

Thanks Terry,
I'm pulling tank to have some real baffle plates installed. At 2g's I have fuel but getting g-slosh at about 1/2 tank. The foam made it better to just under 2g's but it's worse now that I've gone to slicks and E85.

At WOT I'm commanding 7.4 afr. Going lean with this configuration would be disastrous.

[positron]

It comes out the bottom but there seems to be just one angle of the dangle that it wants all others seem to be impossible. Not insurmountable but doable.

Finally found a solution that will go below 1/4 tank at 2+g without running pump dry. Worse case scenario at Fontana was 64 sec of g slosh unfavorable to LH bucket. Best case has some off throttle decel just past 140 to 110 turn entry but all is right of g centerline.

[payne]

[quote="Positron"]
It comes out the bottom but there seems to be just one angle of the dangle that it wants all others seem to be impossible. Not insurmountable but doable.

Finally found a solution that will go below 1/4 tank at 2+g without running pump dry. Worse case scenario at Fontana was 64 sec of g slosh unfavorable to LH bucket. Best case has some off throttle decel just past 140 to 110 turn entry but all is right of g centerline.
[/quote]

What was your solution?  I should have my roller here in in few weeks, and I'd like to replicate before I install my driveline to save a bunch of time down the road.

Also, what fuel pump are you running, and at what hp leve;?  I'm looking at 300-330rwhp on E85, and want to know if I should upgrade my fuel pump to handle the power.

Thanks,
Jason

[CalScot]

Dennis,
Not sure it is of any help because I'm not sure it your frame & tank is the same as mine but I can get the tank out without removing the engine. It's tight and does not look like it will go on visual, but it does wiggle out.
I built a new tank with baffles. Cost me $400 from a local fabricator. It made a huge difference as I'd get fuel starvation at times on a half tank on track. I had to modify the fuel level float arm to get the baffles in and and I upgraded the fuel pump while I was at it.

[payne]

[quote="CalScot"]
I upgraded the fuel pump while I was at it.
[/quote]

What pump did you go with?  Walbro 255?  I can get at mine really easy right now, so I want to upgrade if need be.

[CalScot]

[quote="payne"]
[quote="CalScot"]
I upgraded the fuel pump while I was at it.
[/quote]

What pump did you go with?  Walbro 255?  I can get at mine really easy right now, so I want to upgrade if need be.


[/quote]
Yes it was the Walbro 255. I had to have an adaptor ring made up for it to fit/mate properly into the existing fuel tower assembly. At first it seems to fit ok but if you wiggle it about, you'll see it's not really going to stay in there securely for a long time. Last thing you want is to have to take it back out and of course it would fall out and your car would stop when your 500 miles from home according to Murphy's law. Maybe the one you have will be ok but it's worth making sure.

It's probably worth baffling your tank some too while your at it if you've not already done so. If your going to run E85, your going to need all of that small tanks capacity and sputtering on hard corners with a half tank on track is no fun.

[positron]

It'll come out the bottom after removal of the hoses and stuff. 
First go round was walbro 225 HP and two baffles with 1000cc injectors. But it still over sloshed the plastic bucket. 

Second go round was an internal swirl pot with another walbro feeding the main walbro and only one baffle for weight transfer slosh mitigation. 

I ran full 25 min sessions  at Infineon a couple weeks ago when I could only run about 18 min with and without cell foam.

[CalScot]

[quote="Positron"]
It'll come out the bottom after removal of the hoses and stuff. 
First go round was walbro 225 HP and two baffles with 1000cc injectors. But it still over sloshed the plastic bucket. 

Second go round was an internal swirl pot with another walbro feeding the main walbro and only one baffle for weight transfer slosh mitigation. 

I ran full 25 min sessions  at Infineon a couple weeks ago when I could only run about 18 min with and without cell foam.
[/quote]
On full tilt, my car runs out of 110 octane in about the same time. It also has 1,000cc injectors so that sounds about right for a small tank like ours.

Sounds like it's about time I came out for a run around with you as your wee beastie is getting seriously fast

[positron]

Yeah but my 110 E85 is $3.49/gal. $8/gal at 6/session was getting painful on a 10 session weekend. Engine fast.. Driver not so much.

Not going to be able to make LS this coming mon/tues. Next event is SM in May. Unless you have something in the queue.

[CalScot]

[quote="Positron"]
Yeah but my 110 E85 is $3.49/gal. $8/gal at 6/session was getting painful on a 10 session weekend. Engine fast.. Driver not so much.

Not going to be able to make LS this coming mon/tues. Next event is SM in May. Unless you have something in the queue.
[/quote]
The race fuel does make for an expensive weekend. If I run the Atom on track this year, it will be with regular fuel and street tune. I am planning on running the F2000 series but that might be cancelled due to more family health issues. If I run it, there will be little Atom activity for me except street runs. If I cancel, I will likely do a several Atom track weekends and probably organise another Atom meet this summer.

[payne]

[quote="Positron"]
It'll come out the bottom after removal of the hoses and stuff. 
First go round was walbro 225 HP and two baffles with 1000cc injectors. But it still over sloshed the plastic bucket. 

Second go round was an internal swirl pot with another walbro feeding the main walbro and only one baffle for weight transfer slosh mitigation. 

I ran full 25 min sessions  at Infineon a couple weeks ago when I could only run about 18 min with and without cell foam.
[/quote]

I've not seen an internal swirl pot before.  Did you fab it yourself, or is it an off the shelf unit?  How does the in-tank walbro pull from the pot?  Any pics perchance?

sock/pickup -> walbro -> swirl pot -> walbro -> out of the fuel cell into the fuel filter?  Am I understanding that right?

Does your swirl pot then just push excess fuel out of a vent at the top back into the main tank area?  Are both walbros running off the stock wiring?  Did you have to change a relay or fuse for the extra draw?

Thanks,
Jason

[positron]

Necessity and laziness are the mother of invention.

Didn't have room for a pot in the spare tire well where the drag guys put them. Concept same, same pump setup in tank fills swirl pot, pump in swirl pot feeds fuel rail. Except its all in the main tank. Made another relayed circuit to run second pump triggered by first pump.

Wasnt really necessary until I got within 3 secs of calscot. So I wouldn't say it was necessary for a street car even with E85 unless you run a track that has a hard RH G loading of greater than 34 secs.  LS not so bad, infineon can be iffy, Fontana a must.

Peter - if it were under more fortunate circumstance I would be glad to run with you again.

Found out today they are going to allow my Volt to run at the refuel alt fuel event at LS this year so I'll need some slicks to run. 
So hoping Peter's party bus has 240VAC genset.

[CalScot]

[quote="Positron"]
Necessity and laziness are the mother of invention.

Didn't have room for a pot in the spare tire well where the drag guys put them. Concept same, same pump setup in tank fills swirl pot, pump in swirl pot feeds fuel rail. Except its all in the main tank. Made another relayed circuit to run second pump triggered by first pump.

Wasnt really necessary until I got within 3 secs of calscot. So I wouldn't say it was necessary for a street car even with E85 unless you run a track that has a hard RH G loading of greater than 34 secs.  LS not so bad, infineon can be iffy, Fontana a must.

Peter - if it were under more fortunate circumstance I would be glad to run with you again.

Found out today they are going to allow my Volt to run at the refuel alt fuel event at LS this year so I'll need some slicks to run. 
So hoping Peter's party bus has 240VAC genset.
[/quote]
Well whadaya know, both the motorhome AKA "gin palace" and my trailer have generators that have 240 vac outlets