Reminds me of BMW's marketing phrase. "The relentless pursuit of perfection". In your cars it's "The relentless pursuit of weight loss"

 

Nice job with the old Colin Chapman "...add lightness" theory. Porsche would charge serious money for this amount of weight reduction.

Having flown aircraft and done weight/balance calculations based on a (mostly) single fulcrum-the wing, I'm kinda certain your calculations will be slightly off. The weight outside the wheelbase probably applies a high % to that end of the car. The weight between the wheels, is probably more of a proportional loss.

No matter, full credit and an excellent job of attacking weight loss. A bit here, a bit there and it all adds up and gets significant.

 

It's getting better and better - slowly but surely!

You're absolutely right, which is why I wanted to make sure to say it was wonky math and a guesstimation! When looking at where on the car weight is lost, I keep a mental note of which end it's coming from and whether its inside or outside of the wheelbase. The only 'extreme' weight loss from outside the wheelbase thus far has been the muffler. But the car has enough of a rear weight bias to afford that.

If I can get the lightweight bumper beams (either from AMR or my fabricator), it'll help shift weight further to center and there won't be much extra/excess weight left outside of the wheelbase.

 

My friend (an engineer for Honda) and I were just discussing lightweight bumper beams for our s2000 race cars. After losing over 300 lbs from the car, it's about the last major area to attack. After that, it'll be a pound or two here and there.

I think you're definitely on to something that can have both weight and balance, positive effects

 

Mr. Nimble, Another couple of "blocks" for your profile photo?

Draining the full bottle of fluid from your windshield wiper system will save 11#. Then pull the Owner's Manual from the Glove Box and save 2# more.

 

I've got the typical crack in my windshield washer fluid container, so it's never more than half-full anyway lol. Owner's manual is removed while on track, too.

I actually started looking at titanium bolts last week, just out of curiosity. Cost prohibitive for most things, definitely, but I might do them for specific areas. Right off the bat, I'd use them for the front and rear bumper beams, as those are the best places to lose weight right now. I think they weigh 40% as much as the originals, but the cost-benefit is outrageous when looking at widespread use throughout the car. A dozen or so for the front and rear bumper beams would be the best use for them given their cost.

I looked at titanium lug nuts, but those are silly expensive for the under-0.5-lb weight loss. For perspective, my battery kit costs less than titanium lug nuts (including the battery) and drops 59x as much weight as the lug nuts If someone needs aftermarket lug nuts and puts their car in shows and whatnot, it'd be a really cool thing to do. But strictly regarding weight loss, the cost-benefit just isn't there for me. Yes, it's unsprung rotating mass, but they're nearly center on the rotation point so the benefit isn't as pronounced as, say, lighter tires.

The way it's looking, I might be able to hit 3300 lbs in this thing...

 

Talked to my fabricator about doing lightweight versions of the front and rear bumper beams.

"Would be an insane jig to construct this properly. Cost’s for setup extremely high and not worth it IMO. "

So unless there was enough interest to do a batch of them, it'd be too cost prohibitive anytime soon.


Still waiting to hear back from AMR on their versions.

 

The sliders, side mounts, and bolts (plus additional washers and spacers, not sure if needed yet) add up to 10 lbs. Recaro lists the Profi SPG at 15.5 lbs. That's a total weight of 25.5 lbs. I'll be weighing the OEM seat and components once I have my new seat installed

 

You know Recaro has aluminum seat brackets

 

Yeah, I know

These are the ones I got from Aston Martin Racing, though. Might swap them out for aluminum ones if fitment tests and everything else goes well.

 

Follow-up on the aluminum seat brackets:


The steel ones I have are specific to the Profi SPG. The aluminum ones should fit the the Profi XL, which is wider. So although I'd lose ~2 lbs per seat by going with the aluminum ones, I'd have to use adapters and/or modify the aluminum mounts to fit the seat.

I did that on the Pole Position I put in my STi, which included drilling new mounting holes for the seat to bolt up. On this, I'm looking to keep everything as plug-and-play as possible.

 

Interesting... I have the aluminum ones and the Recaro sliders in my race car and it works with my Recaro Hans Pro Racer Seat that is very narrow. But I would go with the guidance you received. Let me know if I can help measure anything for you.

 

Thanks for the offer, I might take you up on that!


The seat is slated to arrive tomorrow and I'm super excited about it - been looking forward to this project for ages. But I've also got a set of Porterfield R4 pads arriving today from Stuart, plus doing intake filters and hopefully gear oil all this week, so I might not have any pics or videos until this weekend with everything I've got to get done.

 

Just arrived. Initial butt test is extremely positive. Super excited about this!

 

Nice, eager to see more !