Weight reduction: Running out of ideas.

[69427]

IIRC the stock fuel tank in my car is 16 gallon capacity (and twenty something pounds empty IIRC). I've been kicking around for a while the possibility of fitting an 8 to 10 gallon tank from a junk car somewhere and adapting it to mine. The smaller tank should be lighter and smaller in size, which would hopefully allow mounting it on the passenger side of the frame centerline. This would improve L/R weight ratio (but obviously "worsening" F/R weight ratio, but I'll gladly take the hit when reducing total vehicle weight), and reduce lateral weight transfer due to fuel slosh in the corners.
I made a "spa day" at the local Pik-N-Pull today to see what I could find, and pretty much struck out. All the compact cars I could crawl under had pancake shaped tanks, while the Corvette tank is shaped like a big stick of butter. Ideally I was hoping to find a tank that was about 12" by 12" by 15-18" long. I'm not terribly encouraged at the moment, but I'll keep looking.
Another item that may not work out is replacing my aluminum coolant expansion tank with a newer plastic piece. On a slow day sometime I might pull the tank and see what the empty weight of that thing is, and than take my small scale with me on the next trip to the junkyard to compare weights. Until somewhat recently I had a damaged spare aluminum expansion tank, and I had planned on cutting the tank vertically in half at the middle, and then welding a new vertical wall there, reducing the weight and coolant volume. But, it has disappeared during one of my moves the past decade, so scratch that plan.

 

[rtj]

This probably doesn’t have any cert, but I’m thinking about using it as a passenger seat. Looks like a copy of a Kirkey pro street.

6 lbs, under $450

Amazon.com

 

[phantomjock]

I've been working the floors - drooping them about 2" for seating height. Reg says; a minimum of 2 inches from top of the helmet to top for roll bar/cage. But my "skull bucket" would still "tap" the cage - so I am dropping the floors. [Don't raise the bridge - Lower the Water -obscure movie reference}.



The regs don't specifically spec Aluminum seats, so those CF would be a nice addition. Or take lessons from Pappy and DIY!
The regs do spec :

• One-piece bucket seat: For most events, the driver's seat must be a one-piece, bucket-style race seat that provides strong fore/aft and lateral support.
• Secure mounting: The seat must be securely mounted to the floor, cage, or transmission tunnel. Bolting through aluminum floor panels is prohibited unless a backing plate of equal or greater thickness is used to distribute the load.
• Headrest: A system to prevent whiplash and keep the driver's head from striking the roll hoop is required. Racing seats with an integral headrest meet this rule.
• Harness routing: Aftermarket seats must be installed according to the manufacturer's guidelines and provide appropriate routing for a 5-point (or more) harness.
• Mounting hardware: All bolts and nuts used for seat mounting must be a minimum of SAE Grade 5 or Metric 8.8.

Rules by racing program
Regulations can differ between SCCA's racing programs (e.g., Solo vs. Time Trials). You should always check the most current rule set for your specific event.

• For Time Trials and Club Racing: Aftermarket seats are permitted and must meet the general specifications for safety and mounting.
• For Solo (Autocross): Depending on the specific class, factory original seats may be required. In some cases, a driver's seat may be replaced with a one-piece bucket seat, but stock seats often cannot be modified for harness installation.
• For Club Spec: In programs like Club Spec, different safety levels dictate what interior modifications are permitted. Upgrading to aftermarket seats and restraints is typically allowed at higher safety levels.

Take that for "what it's worth" its an AI ref, but pretty close to facts. I'll be in Special Production - so some open options - but the safety section [Chapter/Section/Appendix 9] is not a waver-able item.

BTW, all the form cars tend to use the floor pan and rear firewall with a foam insert as the seat. I've considered that too.

Cheers - Jim