So after reading all 20 pages of this thread, I immediately got out the hole saw to start lightening my helmet, and then remembered to take it off first.

Hope I remember all this stuff correctly.

It took nearly 15 pages of replies until it was finally discussed the "stainless K's" were lighter mainly because of thinner material, which is really a poor choice of material for a repeatedly loaded suspension structural member as it work hardens with stress and soon cracks.

After finally stumbling into alum hood pins instead of steel, nobody? has mentioned rifle drilling them?

Alum for exhaust use, is not very dependent on the alum alloy chosen at the temps expected, its all close to the fail temp. And few seem to consider at even a lowly 200F, alum is starting to lose a lot strength, all factory temper will lost in first heat cycle, which just might anneal/soften alum enough that it might reduce any potential cracking, and wonder what corrosive exhaust effect may play a higher temps, with added question of race fuel additives. I was always led to believe keeping exhaust temps high (flow) was the goal, which alum does not do, and stainless does very well , alum needs to be thicker vs Stainless, which is another heat loss downside, and I wonder does this offset any performance gain in having less weight. I also wonder is a high temp ceramic exhaust coating possible and/or beneficial here?

I believe the first crossmember welder was spot on. A big /high HP car with TB's loading the crossmember, made out of welded alum, when steel has been proven to fail, with ground? welds, is a potential failure waiting to happen, IMO. The added fillet gussets are a nice improvement.

TI wheels studs if used on the street are hopefully known to have finite fatigue life, very unequal to steel.

Are composite leaf springs ever used on drag cars, because they are much lighter.

Never saw any mention of ring gear lightening.

I cringe when I see seat mounts lightened, big holes in flimsy alum? Really?

5/8" Dia Ti Bolts in front Leaf hangers.

Anybody make Ti Rear axle U bolts/tall nuts?

I think anybody going to these lengths would use a CF DS. Concern over rock induced nicks, if a real problem, would be likely only for the street crowd.

For the drag crowd, it is possible to have hollow TB'S factory sized in the lighter rates.

A current car I'm working on, since it will see street use, I'm only using one wheel of internal disc/hat parking brake.