Crossover fuel tank system

Curious if there is a known list of cars that had this installed?
the ones with the 4" cross link between the side bag tanks that ran under the drivers knees.

Chassis 1040 which is a MK I had it.
Chassis 1046 the MK II lemans winner had it.
presumably chassis 1015 that Miles drove in the 66 race also had it installed.

Any other chassis numbers that anyone knows about, particularly interested in an MK I chassis as i would like to know if the gear shift lever casting would have been moved higher. would like to find some photos. I don't think it would clear the tube in the standard position.

Ryan
 

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Randy V

Admin
Lifetime Supporter
I spent quite a bit of time trying to figure out how to implement this on my GT and came to the conclusion that the crossover would have to be forward or aft of the tub unless I was willing to give up the tunnel that my coolant pipes were to run through..
 

Morten

Mortified GT Asylum
Supporter
With only one filler cap on my mk2, I’m also looking for a solution. Not keen on running a fuel line inside the cockpit, so it will run under the recess in oilpan tied to a separate crossmember.
 
The fuel crossover system fitted to the Mk.IIs was different to that fitted by FAV to the Mk.Is although the principle was the same. The easiest way to check which GT40s had it is to count the filler caps.

From memory, these Mk.Is had it:

1001, 1007, 1017, 1029, 1038 and 1040 plus the Gulf cars.

Regards,

Graham.
 
Thanks Graham, i will have to look those up.
I think X-1 also had a crossover as well, not sure how to classify this one though as its something of an in-between car. Different chassis again and was later converted to MK II spec drive-line prior to its 1966 12 hrs of Sebring win.

Ryan
 
I have only been able to find those few photos of p1040.
Would like to see a few more of the other MK I’s and the interiors. We’re the MK I systems a 4” crossover as well?

Did they have to move any of the sponson d ribs to fit it all in?

Ryan
 

Terry Oxandale

Skinny Man
Supporter
No, to reduce the time and manpower required to refuel.
I must be missing something then. It seems like vast overkill in that a 4" tube/pipe is going to flow WAY more fuel than any flow rate allowed through the filler hose under the cap. If one was filling from one side only, and assuming a 2" hose is used for the filler hoses, then wouldn't anything bigger than ~1.50" (allowing both tanks to fill simultaneously at equal rates) between both tanks be useless? Was the fuel pressurized when filling up?
 
The 4” hose may have added a degree of reliability to the system as well, it would allow a degree of strength that a smaller hose would not.
The 4” rubber hose also gets pinched down to a smaller height to pass under the coolant and oil pipes that run lengthways through the central tunnel. End result is that the overall flow may be restricted down to the 1.5” you describe.
 

Ian Anderson

Lifetime Supporter
Supporter
When a cross over fuel line was used, did they not then move the coolant lines into the left sponson?

with a 4 inch pipe did they not get a lot of fuel sloshes across the car during cornering?
ian
 
When a cross over fuel line was used, did they not then move the coolant lines into the left sponson?

with a 4 inch pipe did they not get a lot of fuel sloshes across the car during cornering?
ian
No the coolant pipes weren't moved and baffles/flaps were used to control any fuel movement.

Regards,


Graham.
 
I must be missing something then. It seems like vast overkill in that a 4" tube/pipe is going to flow WAY more fuel than any flow rate allowed through the filler hose under the cap. If one was filling from one side only, and assuming a 2" hose is used for the filler hoses, then wouldn't anything bigger than ~1.50" (allowing both tanks to fill simultaneously at equal rates) between both tanks be useless? Was the fuel pressurized when filling up?
I think you're overthinking this. The original system with 2 separate tanks and 2 separate filler caps, took twice as long to refuel particularly as there was a limit to how many mechanics could work on the car at one time. As most (but not all) race tracks ran clockwise, the LH filler was blanked off and only the RH filler used. This could be swapped over for the odd anti-clockwise circuit. The major problem wasn't getting the fuel in, it was allowing the displaced air to escape.

Regards,


Graham.
 
As I remember, the flapper valve was bolted to the the inner tank wall. The order, as I remember was flapper valve, gasket, tank sponson wall, gasket, rubber bladder of the fuel cell and then the cast backing plate that was tapped for the bolts. At rest in the car the valves hung, so that they were slightly open, allowing flow from one tank to the other. The valve on the outside of a turn closed due to centrifugal of the force of the fuel flowing in from the opposite tank, its valve being open from the centrifugal force. They were as simple as you could get, with a weighted flapper on each side, the weight on the inside of the car towards the seating. At least on my car both gas caps were functional. The valves sealed very effectively. I fact, I ran one tank dry because the valve stuck in the closed position. This setup was used because, it provided fuel that maintained the balance of the car throughout the race. That is, it was self leveling and there by did not change the side to side weight distribution of the car as fuel was consumed. It also made it possible to pull fuel from one tank and not have to have two sets of pumps. Each team made small changes to the MKII's as they thought IT would give them a advantage. Example, XGT1 an Alam Mann car had an aluminum roof structure, not steel to save weight, different than Shelby and Holman & Moody steel structures.

Bill K
 
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