mender

Try this engine: 800cc of tiny CDi terror, can be chipped to 62 whp and should extend your time between fuel stops to 13 hours.

Might be easier to figure out a sheet metal bulkhead that closes off the trunk area, hard to tell from the picture.

Let us know what you find out. How many races have you run with the stock OEM parts?

It's all stock stuff in the trunk of the car, not fuel cell or fuel lines that pass through the cabin. Not seeing a rule that forces people to change or cover OEM fuel parts, only aftermarket/fuel cell parts.

If so, make sure you don't replace that easily cut stock rubber filler tube with an aftermarket filler tube like this: You'll have to put in a metal bulkhead to protect it even though it's much thicker and tougher than the OEM rubber filler hose. 'Cause OEM fuel related stuff that meets the absolute minimum standard and may not even do that much because of accountants that manage to substitute materials on the assembly line to save a few pennies per car is soooo much safer than fuel cells and related parts that were designed to survive in an actual racing environment.

Where's the fuel cell? Looks like stock stuff to me ...

The mighty 150 hp Blue Flame six? The pinnacle of the stovebolt six from 1929? Pushrods, nasty combustion chamber design, 4 main bearings, heavy (but forged) crank, barely managed to get out of the Stone Age by getting hydraulic lifters, bypass oil filter, bearing shells instead of babbit, etc. At the time though it was a reasonable competitor to the Ford flathead. I built my '54 Chev truck engine with a Blue Flame spec cam (just a 261 cam), porting, and a custom long runner 4 bbl intake. Dyno tested at 112 hp and 224 ft.lbs with the stock cam and 1 bbl intake, the cam and my intake bumped that up to 156 hp and 245 ft.lbs, plus in-truck testing showed my carb and intake increased fuel economy by 10%. Idles dead smooth at 450 rpm (can almost count the fan blades) and is all done by 4000 rpm.

He did a Smokey!

Anchor, strap, or tie-down bolt?

So, back to the topic. So far there appear to be at least two cars that have suffered stock strap failures for whatever reason: Ford Focus (strap anchor point) Honda Civic (unknown failure mode) Any others? Might be a good idea to see if these are isolated events or endemic of an issue that should be looked into.

NASCAR engines have pushrods ...

Thanks! Only thing I could find is that a strap failed, not the tank. Too bad there wasn't a follow-up to verify the failure mode.

I've used a rag wrapped around an air nozzle to seal to the filler neck amd supply low pressure air to pop out the almost ubiquitous dent in the bottom of rear mounted fuel tanks in cars that have been bounced across a field. Certainly didn't get anywhere near 100 psi, would be surprised if it reached even 10 psi before the dent popped out. Even more certainly didn't come near having a tank strap fail.

When?

To paraphrase: cheapness is the mother of invention.