TurboPhil's Shop Log

[DarkLotus]

Originally Posted by DWilde

great mod! thanks for all the useful info you provide here! does the fuel tank have a baffle system to also help prevent this issue?

This is my question as well. Couldn't the actual fuel tank be designed to help to mitigate this effect of fuel-slosh?

Example: 1" above the bottom of the fuel tank is a sheet of aluminum with a narrow slit directly in the middle to allow fuel from above to fall down. the 1" sheet is above the fuel-line from the tank. This would ensure at least 1" worth of fuel that can't slosh up and away in extreme banking maneuvers.



I am no engineer, but it seems like this would work?

[DarkLotus]

Also, in thinking about it, the slit could be on the very far side above the fuel-out-line, preventing any fuel, pretty much from getting out and sloshing up when the car is turning in such a way to move fuel away from the fuel-out-line.

[Chococar]

Originally Posted by BrianK

...That may cause your engine to quit (best case) or it may cause you to run lean for just long enough to pop the motor (worst case).

Actually, I think worst case is when you spin and crash because you lose power at the limit.

[...m...]

...i experienced fuel starvation toward the end of my last track session back in august, pitted about one lap after i first noticed it, and then ultimately ran dry on my way to the fuel station a good fifteen minutes away from the track...i hadn't realised it was so potentially dangerous to the motor, though...

[Ol'Racer]

Originally Posted by DarkLotus

This is my question as well. Couldn't the actual fuel tank be designed to help to mitigate this effect of fuel-slosh?

Example: 1" above the bottom of the fuel tank is a sheet of aluminum with a narrow slit directly in the middle to allow fuel from above to fall down. the 1" sheet is above the fuel-line from the tank. This would ensure at least 1" worth of fuel that can't slosh up and away in extreme banking maneuvers.



I am no engineer, but it seems like this would work?

You need a certain amount of sloshing/swishing in the tank to keep sediment and contaminants in suspension. 1" would be shallow. Notice that the pickup line is at the bottom and could possibly suck dirty gas. A filter outside of the pickup might work. A separate tank always has fuel movement and little chance for sediment forming, because of it's size and shape. Most are tall and narrow.

When you check out the innards of a tank you wouldn't believe the crap that you can find at the bottom, including pieces of metal from pump handle shavings at gas stations.

[fzust]

Additionally, what you propose is more work and more expensive. The solution Phil is proposing is totally reversible and allows the use of any fuel pump. I had the worst fuel starvation of anyone around. I would get fuel starvation with only 1 pixel down from full! By going to a swirl tank, I reduced the fuel mass required and eliminated the problem.

[Rei]

Ok funny idea but wouldn't having the surge tank installed also increase overall fuel capacity. So in concept if I have my head wrapped around things correctly. The surge tank is basically taking over as the main tank. While the original tank acts as a filler tank? I always felt weird at autoxing the car with a light fuel load due to starving issues.

[EliseAtLeast]

Will this surge tank be made available? How much or is it too early in the game?

[turbophil]

Originally Posted by Rei

Ok funny idea but wouldn't having the surge tank installed also increase overall fuel capacity. So in concept if I have my head wrapped around things correctly. The surge tank is basically taking over as the main tank. While the original tank acts as a filler tank? I always felt weird at autoxing the car with a light fuel load due to starving issues.

Correct on all accounts. The stock tank and pump is just there to fill the surge tank. The surge tank IS what is actually providing the fuel to the engine. So you can run safely run the stock tank low on fuel at AX and not worry about running short of fuel and causing hesitation or motor damage.... Keep in mind that it holds about a liter of gas, so you do need "some" fuel in the stock tank to give the surge tank a little refill on the transition from right to left hand turns

Originally Posted by EliseAtLeast

Will this surge tank be made available? How much or is it too early in the game?

I plan to. I actually made several of these guys to start out. Two were spent in the prototype process, which is typical but I still have a few left that I can pass along. I've got one fella in Cali that will be giving it a try for sure. If there's a demand for it, I'll build more... I've got just about everything in-hand to complete the build of the other tanks.

Pricing: I'll keep it as reasonable as possible, but ya gotta figure, there's a lot bits 'n pieces here and a lot of time. You've got an adjustable fuel pressure regulator, a boat load of swanky AN fittings (they add up quick!), fancy fuel line, weather pack relay setup (different than what's pictured), Walbro pump of your choosing, fabricated splice in kit for the fuel filler neck (for the overflow), and hand crafted aluminum tank/mount that's Lotus specific... Whew, that'a mouth full... So to put all this together, is probably going to cost about $450 or a bit more for the "kit"...

Toughest part about installation is the overflow line to the fuel filler neck. It's a clam-on job, but it's also a bit of a PITA... Much easier with a tilting clamD

Later,

Phil

[Ol'Racer]

Originally Posted by turbophil

there's a lot bits 'n pieces here and a lot of time.
Phil

Might as well add one more while you're at it. I saw a neat setup a few years ago that had a schrader valve. You could screw a gauge on and read the FP. I thought that was pretty trick. Hey, you never have enough bits n' pieces.

[iana]

Phil,

Great solution to fuel issue for FI cars.


Could you expand on this from your earlier post: -


"..........and leave the boost pickup unplugged on the FPR as seen in the mockup pick...."

[iana]

When first reading this topic I had a ' Why didnt I think of this ? ' moment as this overcomes some critical issues with FI cars.

I assume that the FPR is after the fuel rail and returns to your 'pot'.

If so then all you need is to do is a centre entry fuel rail that will cater for the various FI manifolds out there and you have 'THE kit' -

1. Solving fuel surge issues.

2. Enabling constant pressure at the injectors whatever the boost pressure.

I think your solution is superior to anything that can be done in the tank.

The only other things that I can think of is an in-line fuel filter after the 'pot' and positioning the FP gauge so that it looks up.

[iana]

Sorry, I meant that fuel return is to the filler pipe.

[Dragon]

Crap, how did i miss this thread... Those are beautiful...

Any chance of you also making a fuel rail, fuel pressure regulator and return to add to the kit..

[Rei]

Give the guy some breathing room LOL. I agree on what Phil says when the fittings and lines add up and add up quickly. Maybe someone else could maybe make a fuel rail to handle some nice 550 injectors. More proof that a standalone is a must have if your going to go this deep. How about some hints Phil.

[Dragon]

Originally Posted by Rei

Give the guy some breathing room LOL. I agree on what Phil says when the fittings and lines add up and add up quickly. Maybe someone else could maybe make a fuel rail to handle some nice 550 injectors. More proof that a standalone is a must have if your going to go this deep. How about some hints Phil.

Bah, I think Turbophil is a the kind of person that likes to be kept busy and thinking of new designs.

[turbophil]

hehe, thanks guys... I am one of those guys that never sleeps... Always looking for idea starters, too

Fuel rail, check... already working on it. need to work on mounting... Depending on how tied up I get with V day tomorrow (pun intended.lol), I'll try to get some shots taken of the rail so far... I haven't spent but an hour on it, so there's more time needed to get a finished product... To add it to the swirl tank would be uber easy!!!

Best,

Phil

[sleepe]

Our econo-box engines need so many additional parts to make them track reliable/worthy, do Porsches, BMWs, and other mid to high price range ($40,000+)sports cars have similar problems when one expands their performance envelope by tracking? I bet the Cayman doesn't have oil and fuel starvation problems.

Phil is making parts that Lotus should have included in the Exige Cup 255 specifications list. Why didn't Lotus include a swirl pot or the moroso oil pan? (etc.) Lotus must have known fuel starvation would've been a problem considering these a motors pulled from econo-box toyotas.

When I bought my Elise in 2006 I was under the false impression, according to the hype and salesperson, that it was a street car that was ready for the track
in stock trim.

[ZAMMY1]

would you have paid another 10k or so if they did have the other-than-engine mods?
then, the engine mods, 10k more?
it sure would have priced it out of my consideration.
compromises, everywhere in life.
so many really don't hit the track but i'm happy with mine.
my best, sam

[choi0706]

Originally Posted by BrianK

The fuel pickup is on one side of the tank. When the tank is low & you turn the other way, fuel sloshes to the non-pickup side. At WOT on a track with a long sweeper, all the fuel can slosh to the non-pickup side & stay there for the duration of the turn. That may cause your engine to quit (best case) or it may cause you to run lean for just long enough to pop the motor (worst case).

you WILL pop the motor on any FI car..